Master Techniques in Orthopaedic Surgery The Hand 3rd Edition [3 ed.]

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Editors Steven D. Maschke MD Hand and Upper Extremity Surgery Department of Orthopaedic Surgery Cleveland Clinic Cleveland, Ohio Thomas J. Graham MD Chief Innovation Officer Justice Family Chair in Medical Innovations Vice Chair Department of Orthopaedic Surgery Cleveland Clinic Cleveland, Ohio Peter J. Evans MD, PhD Director Upper Extremity Center Cleveland Combined Hand Fellowship and Peripheral Nerve Center Department of Orthopaedic Surgery Cleveland Clinic Cleveland, Ohio

Contributors Joshua M. Abzug, MD Assistant Professor, Director Pediatric Orthopaedics Department of Orthopaedics University of Maryland School of Medicine Deputy Surgeon-in-Chief Department of Orthopaedics University of Maryland Children's Hospital Baltimore, Maryland Ngozi Mogekwu Akabudike, MD Assistant Professor of Orthopaedic Surgery University of Maryland School of Medicine Attending Surgeon Department of Orthopaedic Surgery University of Maryland Medical Center Baltimore, Maryland Donald S. Bae, MD Associate Professor of Orthopaedic Surgery

Department of Orthopaedic Surgery Harvard Medical School Attending Physician Department of Orthopaedic Surgery Boston Children's Hospital Boston, Massachusetts Blaine Todd Bafus, MD Assistant Professor of Orthopaedic Surgery Case Western Reserve University Hand and Upper Extremity Surgeon Department of Orthopaedic Surgery The MetroHealth System and Department of Veterans Affairs Cleveland, Ohio Mark E. Baratz, MD Clinical Professor and Vice Chairman Department of Orthopaedics University of Pittsburgh School of Medicine Director of Hand and Upper Extremity Surgery Community Medicine, Inc. University of Pittsburgh Medical Center Pittsburgh, Pennsylvania Mark R. Belsky, MD Clinical Professor Department of Orthopaedic Surgery Tufts University School of Medicine Boston, Massachusetts Hand Surgeon Department of Orthopaedic Surgery Newton Wellesley Hospital Newton, Massachusetts Imran K. Choudhry, MD Staff Surgeon Department of Orthopaedics Orthopaedic Associates, LLC Denver, Colorado Michael Darowish, MD Assistant Professor of Orthopaedic Surgery Penn State Milton S. Hershey Medical Center Hershey, Pennsylvania Colleen Davis, OTR/L

Occupational Therapist Hand Therapist Physical Medicine and Rehabilitation MetroHealth Medical Center Cleveland, Ohio Brian M. Derby, MD Physician Sarasota Plastic Surgery Center Staff Physician Department of Surgery Sarasota Memorial Hospital Sarasota, Florida Peter J. Evans, MD, PhD Director Upper Extremity Center Cleveland Combined Hand Fellowship and Peripheral Nerve Center Department of Orthopaedic Surgery Cleveland Clinic Cleveland, Ohio Varun K. Gajendran, MD Hand Surgery Fellow Department of Orthopaedic Surgery Cleveland Clinic Cleveland, Ohio Thomas J. Graham, MD Chief Innovation Officer Justice Family Chair in Medical Innovations Vice Chair Department of Orthopaedic Surgery Cleveland Clinic Cleveland, Ohio Beatrice L. Grasu, BS, MD Orthopaedic Surgery 4th year Resident Department of Orthopaedic Surgery The Curtis National Hand Center MedStar Union Memorial Hospital Baltimore, Maryland Warren C. Hammert, MD Associate Professor of Orthopaedic and Plastic Surgery Department of Orthopaedic Surgery

University of Rochester Medical Center Strong Memorial Hospital Rochester, New York Heather R. Harrison, MD Clinical Fellow Department of Orthopaedic Surgery Cincinnati Children's Hospital Medical Center Cincinnati, Ohio Mark F. Hendrickson, MD Staff Department of Plastic Surgery Cleveland Clinic Cleveland, Ohio James P. Higgins, MD Chief Curtis National Hand Center Union Memorial Hospital Baltimore, Maryland Harry A. Hoyen, MD Associate Professor Department of Orthopaedic Surgery Case Western Reserve University and Cleveland Combined Hand Fellowship Chief Hand Service Department of Orthopaedic Surgery MetroHealth Medical Center Cleveland, Ohio Helen G. Hui-Chou, MD Hand Surgery Fellow Division of Hand Surgery Department of Orthopaedics The Curtis National Hand Center MedStar Union Memorial Hospital Baltimore, Maryland Lawrence C. Hurst, MD Professor and Chairman Chief Division of Hand Surgery Department of Orthopaedics The State University of New York Stony Brook, New York

Aaron Insel, MD Orthopaedic Hand and Upper Extremity Fellow Department of Orthopaedic Surgery Stony Brook University Hospital Stony Brook, New York Ryan D. Katz, MD Faculty The Curtis National Hand Center MedStar Union Memorial Hospital Baltimore, Maryland Michael W. Keith, MD Professor Department of Orthopaedics Case Western Reserve University Director Hand Surgery Department of Orthopaedics MetroHealth Medical Center Cleveland, Ohio L. Andrew Koman, MD Professor and Chair Department of Orthopaedic Surgery Wake Forest School of Medicine Wake Forest Baptist Health Winston-Salem, North Carolina Scott H. Kozin, MD Chief of Staff Shriners Hospitals for Children-Philadelphia Clinical Professor Department of Orthopaedic Surgery Temple University Philadelphia, Pennsylvania Donald Lalonde, BSc, MSc, MD, FRCSC Professor Department of Plastic Surgery Dalhousie University Plastic Surgeon Department of Plastic Surgery Saint John Regional Hospital Saint John, New Brunswick, Canada

Gregory A. Lamaris, MD, PhD Plastic Surgery Fellow Department of Plastic and Reconstructive Surgery The Cleveland Clinic Foundation Cleveland, Ohio Jeffrey N. Lawton, MD Associate Professor Chief Hand Surgery Department of Orthopaedic Surgery University of Michigan Ann Arbor, Michigan Matthew I. Leibman, MD Assistant Clinical Professor Department of Orthopaedic Surgery Tufts University School of Medicine Boston, Massachusetts Department of Orthopaedic Surgery Newton Wellesley Hospital Newton, Massachusetts Kevin J. Little, MD Assistant Professor Department of Orthopaedic Surgery University of Cincinnati School of Medicine Hand and Upper Extremity Surgery Division of Pediatric Orthopaedics Cincinnati Children's Hospital Medical Center Cincinnati, Ohio Susan E. Mackinnon, MD, FRCS(C), FACS Sydney M. Shoenberg, Jr. and Robert H. Shoenberg Professor Department of Surgery Chief Division of Plastic and Reconstructive Surgery Washington University School of Medicine Barnes-Jewish Hospital St. Louis, Missouri Kevin J. Malone, MD Assistant Professor Department of Orthopaedic Surgery Case Western Reserve University School of Medicine Hospital Staff

Department of Orthopaedic Surgery MetroHealth Medical Center Cleveland, Ohio Patrick G. Marinello, MD Orthopaedic Resident Department of Orthopaedic Surgery Cleveland Clinic Foundation Cleveland, Ohio Steven D. Maschke, MD Hand and Upper Extremity Surgery Department of Orthopaedic Surgery Cleveland Clinic Cleveland, Ohio Michael K. Matthew, MD Assistant Professor Department of Plastic Surgery Lerner College of Medicine Cleveland Clinic Staff Department of Plastic Surgery Cleveland Clinic Cleveland, Ohio Michael A. McClinton, MD Associate Professor Department of Plastic Surgery Johns Hopkins Medical Institutions Medstar Union Memorial Hospital Department of Hand Surgery The Curtis National Hand Center Baltimore, Maryland Kenneth Robert Means Jr, MD Attending Physician and Clinical Research Director Department of Orthopaedic Surgery The Curtis National Hand Center MedStar Union Memorial Hospital Baltimore, Maryland Justin B. Mirza, DO Orthopaedic Hand and Upper Extremity Fellow Department of Orthopaedic Surgery Stony Brook University Hospital Stony Brook, New York

Nathan A. Monaco, MD Resident Department of Orthopaedics University of Pittsburgh Medical Center Hamot Erie, Pennsylvania Brian Najarian, MD Associate Faculty Tufts University School of Medicine Boston, Massachusetts Attending Surgeon Department of Orthopaedic Surgery Cape Cod Hospital Hyannis, Massachusetts Michael W. Neumeister, MD Professor and Chair Department of Surgery Southern Illinois University School of Medicine Springfield, Illinois Thao P. Nguyen, MD Resident Department of Orthopaedics University of Maryland University of Maryland Medical Center Baltimore, Maryland Nikhil R. Oak, MD Resident Surgeon Department of Orthopaedic Surgery University of Michigan Ann Arbor, Michigan Loukia K. Papatheodorou, MD, PhD Orthopaedic Surgeon Department of Orthopaedic Surgery University of Pittsburgh Orthopaedic Specialists University of Pittsburgh Medical Center Pittsburgh, Pennsylvania Ebrahim Paryavi, MD, PhD Scientific Research Director The Curtis National Hand Center

MedStar Union Memorial Hospital Baltimore, Maryland J. Megan M. Patterson, MD Assistant Professor Department of Orthopaedics University of North Carolina School of Medicine Surgeon Department of Orthopaedics University of North Carolina Hospitals Chapel Hill, North Carolina Allan E. Peljovich, MD, MPH The Hand and Upper Extremity Center of Georgia Atlanta Medical Center Orthopaedic Residency Program Shepherd Center Atlanta, Georgia Lance A. Rettig, MD Volunteer Clinical Assistant Professor Department of Orthopaedic Surgery Indiana University School of Medicine Indianapolis, Indiana W. Lee Richardson, MD Fellow Hand and Upper Extremity Surgery Department of Orthopaedic Surgery University of Rochester Medical Center Chief Division of Hand Surgery Department of Orthopaedic Surgery Strong Memorial Hospital Rochester, New York Benjamin J. Rogozinski, MD Resident Physician Department of Orthopaedic Surgery Atlanta Medical Center Atlanta, Georgia Jason M. Rovak, MD Hand Surgery Associates Denver, Colorado David E. Ruchelsman, MD, FAAOS

Clinical Assistant Professor of Orthopaedic Surgery Department of Orthopaedic Surgery Tufts University School of Medicine Boston, Massachusetts Assistant Chief of Hand Surgery Department of Orthopaedic Surgery Newton-Wellesley Hospital Newton, Massachusetts Julie Balch Samora, MD, PhD, MPH Clinical Hand Fellow Department of Orthopaedics Brigham and Women's Hospital Boston, Massachusetts Rebecca J. Saunders, PT, CHT Clinical Specialist Research and Staff Development Department of Hand Therapy The Curtis National Hand Center Medstar Union Memorial Hospital Baltimore, Maryland Keith A. Segalman, MD, FACS Attending The Curtis National Hand Center Assistant Professor of Orthopaedics Johns Hopkins University Baltimore, Maryland William H. Seitz Jr, MD Professor of Orthopaedic Surgery Department of Orthopaedic Surgery Cleveland Clinic Lerner College of Medicine of Case Western Reserve University Chairman, Orthopaedic Surgery Lutheran Hospital and Cleveland Clinic Cleveland, Ohio David B. Shapiro, MD Orthopaedic and Rheumatologic Institute Department of Orthopaedic Surgery Cleveland Clinic Cleveland, Ohio Mark C. Shreve, MD Hand and Upper Extremity Fellow Department of Orthopaedic Surgery

Cleveland Clinic Cleveland, Ohio Xavier C. Simcock, MD Hand and Upper Extremity Fellow Department of Orthopaedics Cleveland Clinic Foundation Cleveland, Ohio Beth Paterson Smith, PhD Professor Department of Orthopaedic Surgery Wake Forest School of Medicine Winston-Salem, North Carolina Dean G. Sotereanos, MD, PhD Clinical Professor of Orthopaedic Surgery Department of Orthopaedic Surgery University of Pittsburgh School of Medicine Orthopaedic Specialists University of Pittsburgh Medical Center Pittsburgh, Pennsylvania James W. Strickland, MD Emeritus Professor of Orthopaedic Surgery Department of Orthopaedic Surgery Indiana University Medical Center Medical Director and Hand Surgeon Department of Orthopaedic Surgery/Hand Surgery Saint Francis Hospital Indianapolis, Indiana Catherine Szado, OT/L, CHT Occupational Therapist Department of Physical Medicine MetroHealth Medical Center Cleveland, Ohio Joelle Tighe, BS Research Assistant Community Medicine, Inc. University of Pittsburgh Medical Center Pittsburgh, Pennsylvania Eugene Y. Tsai, MD Resident

Department of Orthopaedics University Hospitals Case Medical Center Cleveland, Ohio Joseph Upton, MD Professor of Surgery Shriners Hospital for Children—Boston Boston Children's Hospital Beth Israel Deaconess Hospital Boston, Massachusetts Carley B. Vuillermin, MBBS, FRACS Instructor in Orthopaedics Harvard Medical School Staff Orthopaedic Surgeon Department of Orthopaedic Surgery Boston Children's Hospital Boston, Massachusetts Peter M. Waters, MD John E. Hall Professor of Orthopaedic Surgery Harvard Medical School Orthopedic Surgeon-in-Chief Department of Orthopaedic Surgery Boston Children's Hospital Boston, Massachusetts Michael D. Wigton, MD Resident Physician Department of Orthopaedic Surgery Allegheny General Hospital Allegheny Health Network Pittsburgh, Pennsylvania E. F. Shaw Wilgis, MD Chief Emeritus The Curtis National Hand Center MedStar Union Memorial Hospital Baltimore, Maryland Bradon J. Wilhelmi, MD, FACS Chief and Professor Department of Plastic Surgery Program Director Plastic Surgery Residency Hiram Polk Department of Surgery

University of Louisville University Hospital Jewish Hospital and Norton Hospital Louisville, Kentucky Raymond A. Wittstadt, MD The Curtis National Hand Center MedStar Union Memorial Hospital Baltimore, Maryland Andrew Yee, BS Research Associate Plastic and Reconstructive Surgery Washington University School of Medicine St. Louis, Missouri Ashraf M. Youssef, MD Resident Department of Orthopaedic Surgery Case Western Reserve University School of Medicine University Hospitals of Cleveland Cleveland, Ohio Jonathan Amer Zelken, MD Curtis National Hand Center Housestaff, Department of Hand Surgery Curtis National Hand Center Union Memorial Hospital Baltimore, Maryland Neal B. Zimmerman, MD Attending Surgeon The Curtis National Hand Center MedStar Union Memorial Hospital Baltimore, Maryland Ryan M. Zimmerman, MD Hand Surgery Fellow The Curtis National Hand Center MedStar Union Memorial Hospital Baltimore, Maryland

2016 Lippincott Williams & Wilkins Philadelphia Two Commerce Square, 2001 Market Street, Philadelphia, PA 19103 USA 978-1-4511-8278-1

Acquisitions Editor: Brian Brown Product Development Editor: Dave Murphy Marketing Manager: Dan Dressler Production Project Manager: David Saltzberg Design Coordinator: Terry Mallon Manufacturing Coordinator: Beth Welsh Prepress Vendor: SPi Global 3rd edition Copyright © 2016 by Wolters Kluwer Copyright 1998, Lippincott Raven Publishers, 2005 Lippincott Williams & Wilkins All rights reserved. This book is protected by copyright. No part of this book may be reproduced or transmitted in any form or by any means, including as photocopies or scanned-in or other electronic copies, or utilized by any information storage and retrieval system without written permission from the copyright owner, except for brief quotations embodied in critical articles and reviews. Materials appearing in this book prepared by individuals as part of their official duties as U.S. government employees are not covered by the above-mentioned copyright. To request permission, please contact Wolters Kluwer at Two Commerce Square, 2001 Market Street, Philadelphia, PA 19103, via email at [email protected], or via our website at lww.com (products and services). 987654321 Printed in China Library of Congress Cataloging-in-Publication Data The hand / [edited by] Steven D. Maschke, Thomas J. Graham, Peter J. Evans. — Third edition. p. ; cm. — (Master techniques in orthopaedic surgery) Preceded by The hand / editors, James W. Strickland, Thomas Graham. 2nd ed. c2005. Includes bibliographical references and index. ISBN 978-1-4511-8278-1 (alk. paper) I. Maschke, Steven D., editor. II. Graham, Thomas J., editor. III. Evans, Peter J. (Peter John), 1961-, editor. IV. Series: Master techniques in orthopaedic surgery. [DNLM: 1. Hand—surgery. 2. Hand Deformities—surgery. 3. Hand Injuries—surgery. WE 830] RD559 617.5′75059—dc23 2015030387

This work is provided “as is,” and the publisher disclaims any and all warranties, express or implied, including any warranties as to accuracy, comprehensiveness, or currency of the content of this work. This work is no substitute for individual patient assessment based upon healthcare professionals' examination of each patient and consideration of, among other things, age, weight, gender, current or prior medical conditions, medication history, laboratory data and other factors unique to the patient. The publisher does not provide medical advice or guidance and this work is merely a reference tool. Healthcare professionals, and not the publisher, are solely responsible for the use of this work including all medical judgments and for any resulting diagnosis and treatments. Given continuous, rapid advances in medical science and health information, independent professional verification of medical diagnoses, indications, appropriate pharmaceutical selections and dosages, and treatment options should be made and healthcare professionals should consult a variety of sources. When prescribing medication, healthcare professionals are advised to consult the product information sheet (the manufacturer's package insert) accompanying each drug to verify, among other things, conditions of use, warnings and side effects and identify any changes in dosage schedule or contraindications, particularly if the medication to be administered is new, infrequently used or has a narrow therapeutic range. To the maximum extent permitted under applicable law, no responsibility is assumed by the publisher for any injury and/or damage to persons or property, as a matter of products liability, negligence law or otherwise, or from any reference to or use by any person of this work. LWW.com

Dedication To Tracie, Mason, Michael, and Lillian, without whom none of my success would be possible. SDM

To my family, colleagues, students, and patients. TJG

To Caroline, my children, colleagues, trainees, and patients. PJE

Series Preface Since its inception in 1994, the Master Techniques in Orthopaedic Surgery series has become the gold standard for both physicians in training and experienced surgeons. Its exceptional success may be traced to the leadership of the original series editor, Roby Thompson, whose clarity of thought and focused vision sought “to provide direct, detailed access to techniques preferred by orthopedic surgeons who are recognized by their colleagues as ‘masters’ in their specialty,” as he stated in his series preface. It is personally very rewarding to hear testimonials from both residents and practicing orthopedic surgeons on the value of these volumes to their training and practice. A key element of the success of the series is its format. The effectiveness of the format is reflected by the fact that it is now being replicated by others. An essential feature is the standardized presentation of information replete with tips and pearls shared by experts with years of experience. Abundant color photographs and drawings guide the reader through the procedures step by step. The second key to the success of the Master Techniques series rests in the reputation and experience of our volume editors. The editors are truly dedicated “masters” with a commitment to share their rich experience through these texts. We feel a great debt of gratitude to them and a real responsibility to maintain and enhance the reputation of the Master Techniques series that has developed over the years. We are proud of the progress made in formulating the third-edition volumes and are particularly pleased with the expanded content of this series. Six new volumes will soon be available covering topics that are exciting and relevant to a broad crosssection of our profession. While we are in the process of carefully expanding Master Techniques topics and editors, we are committed to the now-classic format. The first of the new volumes is Relevant Surgical Exposures—which I have had the honor of editing. The second new volume is Pediatrics. Subsequent new topics to be introduced are Soft Tissue Reconstruction, Management of Peripheral Nerve Dysfunction, Advanced Reconstructive Techniques in the Joint, and finally Essential Procedures in Sports Medicine. The full library thus will consist of 16 useful and relevant titles. I am pleased to have accepted the position of series editor, feeling so strongly about the value of this series to educate the orthopedic surgeon in the full array of expert surgical procedures. The true worth of this endeavor will continue to be measured by the ever-increasing success and critical acceptance of the series. I remain indebted to Dr. Thompson for his inaugural vision and leadership, as well as to the Master Techniques volume editors and numerous contributors who have been true to the series style and vision. As I indicated in the preface to the second edition of The Hip volume, the words of William Mayo are especially relevant to characterize the ultimate goal of this endeavor: “The best interest of the patient is the only interest to be considered.” We are confident that the information in the expanded Master Techniques offers the surgeon an opportunity to realize the patient-centric view of our surgical practice. Bernard F. Morrey, MD

Preface Seemingly since Jim Strickland and I edited the last volume of Master Techniques in Orthopaedic Surgery: The Hand, in 2005, everything in health care has changed. We all recognize that our industry is at an historic inflection point and there is no stakeholder that is immune from feeling pressure and experiencing ambiguity. The largest concentrated sector of our economy is seeing its biggest rate of change ever. What has not changed is that the “center of the medical universe” remains where the doctor and the patient meet. If you are a Hand Surgeon, that comes with a responsibility to be intellectually and technically prepared while exhibiting empathy and concentrating on the patient experience. I do not believe there has been a better vehicle for passing along the nuanced information that may make the difference between success and suboptimal results than this entire Master Techniques series. As I saw these contributions coming in from some of the most accomplished surgeons and educators in our field, I was vividly reminded that our specialty is dynamic. Our colleagues remain innovative problem solvers, keen clinical anatomists, and master technicians. They also take the role as teacher very seriously. I know that all of our readers are lifelong students of Hand Surgery. That is why we remain stimulated after decades of practice—by the subject matter and especially by the opportunity to help the next patient. That is why I am so proud of my two Co-Editors, Drs Peter Evans and Steve Maschke. They are the next generation of leaders who bring all the assets together that make our specialty vital and collegial. Just as Jim passed the baton of responsibility for this book to me, I am humbled to pass it to them. At different times in our career, we are students and teachers…mentors and mentees…some of us have been both doctors and patients. Since the last volume, I almost lost my life to a rare medical illness but came back after over a year away from Hand Surgery to resume practice. I know how important our work is and how precious the gift to do it for a living remains. Whether you are looking at this electronically on a computer or mobile device, or the “old fashion way” with a book in your hand, I trust that the dedication and expertise of the contributors seep through. The medium may have changed, but being the most informed and technically advanced surgeon you can be never goes out of style. You have made the choice to improve your knowledge on behalf of your patients by reading this book. That makes you a Master. Good luck and best wishes. Thomas J. Graham, MD Chief Innovation Officer and Vice Chairman of Orthopaedic Surgery Cleveland Clinic Cleveland, Ohio

Preface to the Second Edition The intellectual and technical challenges of sophisticated hand surgery are practically unparalleled in the endeavors of the clinical sciences. Intimate knowledge of fine anatomy; well-planned and skillfully executed surgical exercises; and attention to detail before the operation, intraoperatively, and during rehabilitation are all required to maximize outcome. Respect for time-tested techniques, with an open-minded approach to evolving surgical options, is demanded if a contemporary surgeon is to deliver the ultimate level of care to the wide array of patients seeking help for hand problems due to traumatic, congenital, inflammatory, neoplastic, or degenerative conditions. The Master Techniques series has already risen to a unique niche in the dissemination of highlevel surgical education. The initial edition of The Hand laid the groundwork for capturing the thinking and unique perspective that our distinguished colleagues have developed over years of practice. Students of Hand Surgery will see that this volume has further expanded the spectrum of procedures and pearls. We credit the laureates who have contributed to this edition with concise words and vivid images. They have captured the salient points by recognizing the germinal components of the problems and the solutions. With tremendous photography and illustration strengthening the descriptions, the compendium of the written word and visual learning tools has resulted in an important contribution to our specialty. Just as we shared the strong bond between mentor and pupil, we wanted to capture that singular experience for teaching and learning. To pass along our true thinking about our work, and ask our valued friends to do the same, is an honor. In this way, all the authors can feel the flexibility and intimacy that come with disseminating knowledge from one colleague to the next in one of the best media we can imagine. All of the contributors appreciated the responsibility of accepting and completing these assignments and fulfilled them expertly. All of those who worked on Master Techniques in Orthopaedic Surgery: The Hand hope that this volume connects with our readers in a way that makes it is a resource and stimulus for their own development. It is a text that is dynamic, not simply a moment frozen in our timeline of hand surgery, but a catalyst for greater discourse and creativity concerning the clinical tests that we all face. Ultimately, there will be acceptance, inquiry, controversy, and change in almost all of the views expressed herein. That is the nature of our specialty and of all of medicine. For now, this is the best effort of many of the most dedicated and prolific contributors to our specialty, who also share a passion for teaching and lifelong learning. We hope the book makes a positive impact on the practice of our readers and in the lives of their patients. Thomas J. Graham, MD James W. Strickland, MD

Preface to the First Edition This book is a collection of descriptions of operations as performed by acknowledged “masters.” There is no attempt to be comprehensive or all inclusive. Instead, common operative procedures have been selected and the preferred operative approach of the author is illustrated and described. A major strength of the volume is the quality of the illustrations. Uniformity of this quality is assured by having the same artist illustrate the entire book. In addition, a single uniform format has been adopted so the reader can easily become familiar with the style as successive chapters are read. The best way to use this book is to read a chapter that pertains to a particular patient and operation that you are planning. Add your own experiences and preferences, but remember that the procedures described have served the authors in numerous circumstances. I guarantee that you will find each chapter useful and informative. Curtis B. Sledge, MD

Video Content Video 10-1

Acute trauma 1.

Video 10-2

Acute trauma 2.

Video 10-3

Acute trauma 3.

Video 10-4

Acute trauma 4.

Video 10-5

Acute trauma 5.

Video 10-6

Acute trauma 6.

Video 10-7

Posttraumatic reconstruction 1.

Video 10-8

Posttraumatic reconstruction 2.

Video 10-9

Burn and congenital hand reconstruction 1.

Video 10-10A

Burn and congenital hand reconstruction 2.

Video 10-10B

Burn and congenital hand reconstruction 3.

Video 10-10C

Burn and congenital hand reconstruction 4.

Video 10-10D

Burn and congenital hand reconstruction 5.

Video 10-10E

Burn and congenital hand reconstruction 6.

Video 10-11A

Surgical technique 1.

Video 10-11B

Surgical technique 2.

Video 10-11C

Surgical technique 3.

Video 10-11D

Surgical technique 4.

Video 10-11E

Surgical technique 5.

Video 10-11F

Surgical technique 6.

Video 10-11G

Surgical technique 7.

Video 10-11H

Surgical technique 8.

Video 10-11I

Surgical technique 9.

Video 10-11J

Surgical technique 10.

Video 10-11K

Surgical technique 11.

Video 10-11L

Surgical technique 12.

Video 10-11M

Surgical technique 13.

Video 10-11N

Surgical technique 14.

Video 10-11O

Surgical technique 15.

Video 10-11P

Surgical technique 16.

Video 10-12

Surgical technique 17.

Video 10-13A

Surgical technique 18.

Video 10-13B

Surgical technique 19.

Video 10-14

Surgical technique 20.

Video 10-15A

Postopertative management 1.

Video 10-15B

Postopertative management 2.

Video 10-16

Results.

Video 11-1

Elson's test for integrity if central slip.

Video 17-1

Pre-op.

Video 17-2

Donor.

Video 17-3

Setting extensor synch tension.

Video 17-4

Confirming tension.

Video 17-5

Post-op.

Video 22-1

Nerve transfer: median to radial nerve transfer presentation.

Video 22-2

Median to radial nerve transfer.

Video 23-1

Post-op.

Video 29-1

Homodigital island flap.

Video 31-1

Arterial and peripheral sympathectomy for vasospastic disease.

Video 33-1

Opposition transfer and UCL reconstruction for type II thumb hypoplasia.

Chapter 1 Surgical Approaches to the Digits and Treatment of Finger Infections Jason M. Rovak Surgical exposure is both basic and critical to any surgical procedure's success. While many surgical disciplines have standard approaches regardless of the underlying pathology, in the upper extremity, the surgical approach can require careful preoperative planning that is tailored to the individual procedure. The approach must maximize visualization while protecting underlying structures both during the procedure and in the course of postoperative healing. A carefully planned approach will also allow for the unexpected intraoperative finding that requires a change of course. In this chapter, we will address common surgical approaches in the digits as well as treatment for common finger infections.

VOLAR APPROACHES TO THE DIGIT The primary principle governing exposure of the volar structures is avoiding linear scars across flexion creases. Since scars contract linearly, scars that cross flexion creases perpendicular to the crease can lead to postoperative flexion contractures. In trauma situations, the exposure is dictated by the P.2 wound, and linear scars may need to be addressed either by proactively redirecting the orientation of the wound during closure with Z-plasties or by addressing the contractures at a second procedure in the subacute/chronic period if a contracture develops. In elective settings, the key is to avoid the problem altogether with careful preoperative planning.

FIGURE 1-1 Index finger: Standard Bruner incisions; long finger: Mini-Bruner incision; ring finger: Bruner incision with curved flap tips; small finger: Incision within the joint flexion crease. There are three predominant methods of avoiding linear scars along the volar axis of the digit. These methods can either be used in isolation or combined: 1. Cross the joint crease obliquely.

2. Place the incision in the flexion crease. 3. Place the incision along the lateral aspect of the digit. The first method entails a series of zigzag incisions that cross the flexion creases at roughly 45-degree angles. The incision extends from the radial to the ulnar aspect of the digit. This approach was originally described by Bruner (1) and provides excellent exposure of all volar structures. These incisions can be extended proximally and distally as far as the situation requires, including the palm and wrist (Fig. 1-1, index finger). Not every situation requires exposure of the whole volar surface, such as a single digital nerve laceration without tendon involvement. In these settings, a “mini-Bruner incision” may be adequate, placing the apex of the incision in the central volar aspect of the digit without extending completely across the digit (Fig. 1-1, long finger). Some surgeons prefer to round off the tips of the flaps to avoid tip necrosis (Fig. 1-1, ring finger). I have not found tip necrosis to be a problem with pointed flap tips. The next method involves placing the incision directly in the flexion crease (Fig. 1-1, small finger). While the incision obviously involves the flexion crease, the direction of scar contracture is parallel to the crease, and perpendicular to the axis of the digit, so it does not lead to flexion contractures. The scar is nicely hidden within the flexion crease for excellent postoperative cosmesis. This method is generally not used in isolation, as it provides only a small window of exposure. I have only used this method in isolation as a counterincision when irrigating the flexor sheath, which will be described later in this chapter, or as an exposure for a trigger finger release, which is well described elsewhere. Finally, incisions can be placed on the lateral aspect of the digit. When correctly designed, these incisions are placed in the “midaxial” line. This line connects the center of the phalangeal condyles when viewed from the side. While linear and crossing joints, an incision in the midaxial line does not contribute to a joint contracture since the scar is directly in line with the joints' axis of rotation. A contracting scar volar to the axis of rotation, on the other hand, provides a flexion force. In order to identify the midaxial line, the digit is placed in flexion and the apex of the joint crease is marked. This indicates the center of the condyle (Fig. 1-2). These points are connected P.3 to form the midaxial line. In isolation, midaxial incisions allow access to the PIPJ for contracture release. More commonly, these incisions are combined with Bruner incisions to provide wide exposure of the volar digital structures as is required when treating extensive infections, treating pressure injection injuries, or performing flexor tenosynovectomy, or in zone II flexor tendon repairs (Fig. 1-3). Some surgeons feel that another advantage to this approach is that it avoids scar tissue across the volar structures, though again, I have not found this to be a problem with a standard Bruner approach.

FIGURE 1-2 Marking the midaxial line. With a flexed digit, the apex of the joint flexion crease indicates the appropriate incision placement.

FIGURE 1-3 Midaxial incisions combined with Bruner extensions. P.4

DORSAL APPROACHES TO THE DIGIT Dorsal approaches to the digits are both more forgiving and more variable. Beginning distally, the nail bed is generally exposed in crush injuries to address nail bed lacerations and open fractures of the distal phalanx. Subungual masses or lesions such as glomus tumors or biopsy for subungual melanomas are addressed similarly. The fingernail can be either partially or totally removed depending on the extent of the required exposure. This is achieved by placing the sharper end of a Freer elevator under the distal aspect of the nail and carefully elevating the nail from the nail bed, taking care to ensure that damaged portions of the nail bed remains with the undamaged portion of the nail bed and do not come off with the nail. The nail is freed from the lateral aspects of the nail fold as well. The elevator is then placed under the eponychial fold on top of the nail, and the nail is removed in an atraumatic fashion. I clear any adherent soft tissue with a Freer elevator, soak the nail in Betadine, rinse with saline, and place the nail on gauze for use at the end of the case. The germinal matrix, under the eponychial fold, is inspected to determine the proximal extend of the injury. Occasionally incisions on

the lateral aspect of the nail fold are necessary to provide adequate proximal exposure (Fig. 1-4, ring finger). A small double hook is used to retract the dorsal roof of the nail fold so the fold can be inspected for masses and the proximal aspect of the nail bed inspected for trauma. Nail bed lacerations and any required incisions in the nail fold can be closed using either 5-0 or 6-0 fast-absorbing gut suture. In order to prevent scar tissue (synechia) from disturbing nail growth, the nail fold is stented open with the previously removed fingernail. I place a horizontal mattress stitch through the dorsal nail fold and through the proximal aspect of the nail to secure the nail under the fold and place one distal stitch through the nail plate and distal tip to prevent the end from catching and avulsing. If the fingernail itself is unavailable, trim foil from the suture pack to an appropriate size and stent the nail fold. Exposing the dorsal aspect of the distal interphalangeal joint (DIPJ) is required to excise mucous cysts or perform DIPJ arthrodesis. Either an “H-” or “Y”-shaped incision provides exposure of the radial and ulnar aspect of the joint (Fig. 1-5, small and ring fingers) and allows proximal and distal exploration if needed. If a mass is situated away from the midline, full exposure of the joint may not be necessary. In this case, the incision can be limited to one-half of the “H” or “Y” (Fig. 1-5, index and long fingers). The dorsal aspect of the proximal interphalangeal joint (PIPJ) can be addressed with either a straight line incision centered over the joint or a curvilinear incision (Fig. 1-6). Skin flaps are easily elevated just over the paratenon of the extensor tendon. In the index, long, ring, and small fingers, the sensory nerve branches innervating the dorsal aspect of the digit arise from the digital nerves on the volar aspect of the digit. These branches are raised within the skin flaps, and I do not make an effort to identify branches during these approaches. The dorsal thumb, on the other hand, is innervated by branches of the radial sensory nerve. These branches are identifiable and if damaged can lead to noticeable numbness or discomfort. For PIPJ arthrodesis, I use a straight line incision, as scar contracture is not an issue. To address stiffness that requires either tenolysis or capsulectomy, I will use a large curvilinear incision. This provides wide exposure of all dorsal structures and also allows access to the lateral and volar structures if necessary.

FIGURE 1-4 Ring finger: Incisions to reflect the dorsal nail fold. Long finger: Marsupialization incisions. P.5

FIGURE 1-5 Dorsal approaches to the distal interphalangeal joint.

FIGURE 1-6 Dorsal approaches to the proximal interphalangeal joint.

INFECTIONS Felon Infections of the volar pad of the fingertip present with pain and swelling, usually preceded by a puncture injury. The fingertip is tense and painful with palpation. Many times, there is an area on the volar pad that is “pointing” and indicates the site of maximum purulence. The symptoms are isolated to the tip of the digit and do not extend proximally into the finger. Motion is generally not painful. The differential for any volar finger infection must include flexor tenosynovitis, septic joint, P.6 and gout, though these are usually easily differentiated with a targeted physical exam. Treatment is primarily surgical. Incision and drainage can be performed under local anesthesia. Lateral incisions can be used to avoid scars and subsequent discomfort over pinch surfaces; however, I generally favor an incision directly over the point of maximum fluctuance and pain. The volar soft tissue has septa extending from the distal phalanx to the skin, and a tenotomy scissors is used to bluntly dissect through the septa to ensure that there are no loculated

collections. The wound is irrigated then packed with ¼-inch plain packing, and a sterile dressing is applied. I have the patient begin range of motion the following day with daily soaks and packing changes until the wound heals. Cephalexin is generally adequate empiric coverage, though oral antibiotic therapy is tailored to intraoperative cultures as results become available.

Paronychia The eponychial fold is a common site for finger infections, especially in patients who pick at hangnails or bite their nails. These present with a focal area of erythema and tenderness over the lateral or proximal eponychial fold. Oral antibiotic treatment alone is frequently successful, and hot water soaks may encourage spontaneous drainage; however, if a conservative course does not resolve symptoms or if the area is fluctuant and does not spontaneously drain, surgical incision and drainage may be necessary. Following digital block, a no. 15 or no. 11 blade is placed through the distal aspect of the eponychial fold with the blade oriented parallel to the nail. The wound is washed out and packed, with local wound care beginning the following day. A 10- to 14-day course of antibiotics should be completed to prevent recurrence. Untreated paronychia can spread to the subungual space or to the volar soft tissues of the digit. In cases with subungual purulence, the portion of the nail overlying the infected bed is removed to adequately drain the infection and release the pressure on the nail bed in an attempt to preserve normal nail growth. If purulence has spread into the volar soft tissues, release of the volar soft tissues can generally be performed through the dorsal incision, though in severe cases, a counterincision in the volar pad can facilitate thorough washout. Chronic or recurring paronychia may develop, especially in those with prolonged occupational water exposure. These tend to be fungal in origin, whereas acute paronychia is typically bacterial. Chronic paronychia can be recalcitrant to standard incision and drainage and may require marsupialization of the eponychial fold. This involves excising an ellipse of dorsal soft tissue just proximal to the eponychial fold, followed by healing by secondary intention (Fig. 1-4, long finger). Oral antifungal therapy may be necessary as well, depending on the offending organism.

Septic Joints Diagnosis of septic DIP and PIP joins is primarily clinical, as arthrocentesis can be technically difficult, and there is generally inadequate fluid available for diagnostics. Pain with axial load and passive motion at the joint is the hallmark of a septic joint. Crystalline arthropathy should always be within the differential, especially in a patient with a previous history. Expedient surgical drainage is key to prevent chondral damage or subsequent osteomyelitis. The joints are approached dorsally as described above. An arthrotomy is created lateral to the midline to avoid damage to the extensor mechanism. At the DIPJ, the capsulotomy is created lateral to the terminal extensor slip. The PIP joint is opened between the central slip and lateral band. The joint is irrigated with a small Angiocath, and I typically place a small Penrose drain in the joint to facilitate continued drainage. Wound care and range of motion begin the following day. I generally remove the drain 48 hours after the initial surgical procedure. I will consult infectious disease for intravenous antibiotics at the time of initial evaluation, though expeditious surgical treatment is key to preventing long-term sequelae. As with any infectious or traumatic insult to the small joints in the fingers, postoperative stiffness is common. Early therapy is key to maximizing the patient's eventual outcome.

Flexor Tenosynovitis Purulent flexor tenosynovitis develops when bacteria are traumatically introduced into the flexor sheath. The infection quickly spreads proximally and distally along the flexor sheath and can cause scarring within the sheath or tendon rupture if not treated urgently. Patient presentation was classically described by Kanaval (2), and the hallmark findings bear his name. Kanaval's signs include (a) fusiform swelling of the digit, (b) finger held in a

flexed posture, (c) pain with passive digit extension, and (d) marked tenderness to palpation along the entire sheath, including the palm over the A1 pulley. I have found the last two to be the most reliable when making the diagnosis, as finger swelling can come from superficial infections, edema, gout, etc., and any finger swelling can lead to a flexion posture. If the patient has pain along the volar length of the digit, including the distal palm, and pain with passive extension, purulent flexor tenosynovitis should be high on the differential. P.7 Incision and drainage can be performed with local anesthesia; however, if I am concerned about additional purulence in the volar soft tissue that may require more extensive dissection, or if appropriate lighting and instrumentation are not available for a safe local anesthesia case, I will perform this procedure in the operating room with general anesthesia. Additionally, extensively infected areas can be difficult to anesthetize. Infected soft tissue has a more acidic local environment. Local anesthetics themselves are weak bases and will not cross cell membranes in their protonated, charged, form. Adding sodium bicarbonate to the anesthesia can increase the chances of successful anesthesia as well as decrease the pain of injection. If the infection is fairly early, local anesthesia has a high chance of success, and I expect a limited tourniquet time I am comfortable using a local anesthesia for these cases either in the emergency department or operating room. If any of the above are in question, it is better to use a general anesthetic, avoiding patient discomfort and movement, which can compromise exposure and efficacy of the washout. An incision is made directly over the flexor sheath in the palm, and blunt dissection is taken down to the flexor sheath just proximal to the A1 pulley. The flexor sheath is usually bulging, and purulence will be obtained as soon as the sheath is entered. I obtain cultures at this time. A volar counterincision is made in the DIP joint flexion crease. The flexor sheath is opened transversely at the A5 pulley level. I will then place a small Angiocath or pediatric feeding tube into the flexor sheath in the proximal wound and flush distally with normal saline. The fluid should flow freely and egress from the distal wound. Occasionally, the digit needs to be slightly flexed or extended to allow easy fluid flow. After copious irrigation, both wounds are packed with either plain packing or a Penrose drain. Again, infectious disease consultation and hand therapy are involved early. I have the patient begin whirlpool the following day, and generally remove the drains 48 hours after the initial washout. The predominant causative organism in hand infections of all types is Staphylococcus aureus. Cephalexin generally provides adequate empiric coverage until culture results are available and also covers streptococcus. Bactrim (trimethoprim/sulfamethoxazole) is also an excellent first-line treatment. While Bactrim does not cover streptococcus, most methicillin-resistant Staphylococcus aureus (MRSA) is sensitive to Bactrim. Bactrim has excellent soft-tissue penetration and oral bioavailability, is inexpensive, and has twice per day dosing, facilitating patient compliance. Cultures should be obtained in the OR with any infection. In cases that clearly require operative management with a readily available OR, I will hold off on antibiotic administration and will counsel the ER to hold off on antibiotic administration, until after the procedure to obtain accurate operative cultures.

CONCLUSIONS Surgical exposures in the digits are varied and must be tailored to the procedure. Preoperative planning should take unexpected pathology as well as possible future operations into account. Adequate exposure not only facilitates successful completion of the procedure at hand but also can prevent future complications directly related to scar tissue formation from the procedure.

REFERENCES 1. Bruner JM: The zig-zag volar digital incision for flexor tendon surgery. Plast Reconstr Surg 40(6): 571-574,

1967. 2. Kanavel A: Infections of the hand. 4th ed. Philadelphia, PA: Lea & Febiger, 1921.

Chapter 2 Palmar Approaches Michael Darowish

CARPAL TUNNEL APPROACH Indications The carpal tunnel may need to be approached for median nerve decompression for isolated carpal tunnel syndrome, for acute carpal tunnel syndrome, or in conjunction with fasciotomy for compartment syndrome. The carpal tunnel may also need to be explored in cases of infection or penetrating trauma, or may need to be opened to identify retracted proximal stumps of finger flexor tendons during repair or reconstruction. The carpal tunnel approach can be extended proximally into the volar approach of Henry to address fractures of the distal radius, as well as permitting access to the volar wrist ligaments, such as in the case of perilunate dislocations. Similarly, tenosynovectomy of the flexor tendons for rheumatoid disease or mycobacterial infection can be performed through this extended approach (Fig. 2-1).

Technique A variety of approaches for decompression of the median nerve have been described, including one- and twoportal endoscopic, proximal or distal minimally invasive releases, or more traditional open approaches. Regardless of the approach chosen, certain anatomic considerations remain constant. The carpal tunnel runs from Kaplan's cardinal line distally to the wrist flexion crease proximally. Just distal to the transverse carpal ligament (TCL) and the carpal tunnel lays the superficial palmar arch, typically 18 mm distal to the distal edge of the ligament (1). The TCL attaches to the scaphoid and trapezium radially and the pisiform and hamate ulnarly. The recurrent motor branch of the median nerve must be protected. Its anatomy is variable. Most commonly, the nerve arises distal to the carpal tunnel, traveling proximally to the thenar muscles. However, approximately 30% of the time, the nerve branches within the carpal tunnel, and then travels in the tunnel until just distal to the TCL, where the recurrent branch turns superficially and radially back into the thenar muscles. Alternatively, approximately 20% of the time, the recurrent branch comes off the median nerve within the carpal tunnel and pierces through the TCL into the thenar musculature (transligamentous). More rare variations include the recurrent branch arising from the ulnar side of the median nerve, multiple motor branches, or division of the median nerve proximal to the carpal tunnel, with the motor nerve then following any of the paths described above to reach the thenar musculature (Fig. 2-2). Because of this high degree of variance, care must be taken when dividing the TCL to mitigate the potential for iatrogenic injury to the motor branch. By approaching the TCL at its ulnar border, greater distance from the recurrent branch is maintained, protecting the nerve. Should the physician encounter a substantially large palmaris brevis or hypertrophic muscle atop the TCL (2,3) or an aberrant accessory flexor pollicis brevis muscle (4), greater care should be taken, as these are associated with a higher incidence of nontraditional course of the motor branch. P.10

FIGURE 2-1 Clinical example of extensile carpal tunnel approach for tenosynovectomy. A: Dots demonstrate the course of the incision. B: After subcutaneous dissection, the median nerve is identified and isolated (Penrose drain is around the nerve). C: After excision of tenosynovitis. The palmar cutaneous branch of the median nerve branches from the median nerve approximately 5 to 6 cm proximal to the wrist flexion crease. It then travels with the median nerve for an additional 2 to 3 cm before running along the ulnar aspect of the flexor carpi radialis (FCR) tendon. At the flexor retinaculum, it travels between the two layers of the retinaculum, ultimately dividing into three branches, providing sensation to the palm overlying the thenar musculature. By staying ulnar and taking care to divide the antebrachial fascia under direct vision, injury to this branch can be avoided. In an open approach to the carpal tunnel, a longitudinal incision along the radial border of the ring finger, starting at Kaplan's cardinal line (a line extended from the ulnar border of the radially abducted thumb), and extending toward the wrist flexion crease just ulnar to the palmaris longus tendon is made. If no proximal extension of the approach is required, the incision should end distal to the wrist flexion crease, as there is some suggestion of increased pain with more proximal incisions. Should the need to cross the wrist flexion crease exist (such as in cases of tenosynovectomy or extensile approaches for trauma), the incision should cross the flexion crease at an oblique angle, taking care to veer ulnarly to avoid injury to the palmar cutaneous branch of the median nerve (Fig. 2-3). Immediately below the skin, there exists a layer of subcutaneous fat. This can be elevated as a pedicled flap based on branches the ulnar artery (hypothenar fat flap) to alter the perineural environment in cases of revision carpal tunnel release (CTR) where significant scarring of the median nerve to the TCL is present. Otherwise, this layer can be divided without consequence. Dissection is carried down to the palmar fascia, which is identified and divided in line with its fibers. The TCL is then visualized. If thenar musculature is encountered on the ligament, the ulnar aspect of its fascia is incised, and the muscle fibers are bluntly swept from ulnar to radial to expose the ligament. Should pockets of fat be

encountered, this should alert the surgeon to carefully dissect these areas, as this is often the sign of nearby neurovascular structures, including the recurrent motor branch. Once the ligament is exposed, it is divided along its ulnar aspect. At the distal end, bright yellow fat is encountered, denoting that dissection has been carried far enough distally, and once again alerting the surgeon to the nearby location of the palmar arch (Fig. 2-4). P.11

FIGURE 2-2 Variations in the course of the recurrent motor branch of the median nerve. A: Extraligamentous. B: Subligamentous division of the median nerve with recurrent entrance to the thenar musculature. C: Transligamentous course of the recurrent motor branch. D: Branching from the ulnar aspect of the median nerve. E: Lying atop the TCL. (From Mackinnon SE, Novak CB. Compression neuropathies. In: Wolfe SW, Pederson WC, Hotchkiss RN, et al., eds. Green's operative hand surgery. 6th ed. Philadelphia, PA: Elsevier, 2011.)

FIGURE 2-3 Incision for proximal extension of the carpal tunnel approach. Note the incision deviates ulnarly to avoid injury to the palmar cutaneous branch of the median nerve (black arrow). (From Catalano LW, Zlotolow DA, Lafer MP, et al.: Surgical exposures of the hand and wrist. J Am Acad Orthop Surg 2: 48-57, 2012.)

P.12

FIGURE 2-4 Clinical photograph (A) and artist's rendering (B) demonstrating carpal tunnel release. Bright yellow fat encountered at the distal aspect of the TCL is a reliable indicator that dissection has extended distally enough to fully decompress the median nerve at the carpal tunnel and that dissection further distally should proceed with care, as the palmar arch is near. (From Madhav TJ, To P, Stern PJ: The palmar fat pad is a reliable intraoperative landmark during CTR. J Hand Surg Am 34: 1204-1209, 2009.) To expose the proximal ligament and antebrachial fascia, dissecting scissors are used to bluntly open a pocket above the ligament, and a Ragnall or House retractor is placed into the pocket to elevate the skin and palmar fascia away from the TCL and antebrachial fascia. By allowing the wrist to extend, the structures to be divided fall dorsally from the more superficial structures, and can then be released under direct vision with a no. 15 blade. During this portion of the case, the surgeon should either move to the end of or move to the other side of the hand table to allow unrestricted visualization and a more controlled release using one's dominant hand.

Tips and Pearls In my practice, for isolated CTR, I typically utilize Bier block (intravenous regional anesthesia) with or without sedation, according to patient preference. Rarely do I have patients who are not willing or able to tolerate this, and general anesthesia is used. I prefer this to local anesthesia, which can blur tissue planes and obscure small nerve branches, which can provide difficulties for the surgeon and when working with trainees. I use a singleforearm tourniquet with 20 to 25 mL of 0.5% lidocaine; forearm tourniquets are well tolerated for these short procedures, and the dose of lidocaine is minimized, allowing the tourniquet to be safely deflated sooner than when larger volumes are used. Because of the short tourniquet duration, a double tourniquet is not necessary. Tourniquet pressure is set at least 100 mm Hg higher than systolic pressure; at least 250 mm Hg, but possibly higher depending on the patient's blood pressure in the operating room. It is critical to set tourniquet pressure high enough to avoid a venous tourniquet, which significantly complicates the surgery and makes visualization difficult, as the tourniquet cannot be deflated for at least 20 minutes after lidocaine injection in order to prevent systemic side effects of the lidocaine. By initiating the block prior to prepping and draping, the anesthetic has typically had enough time to take effect prior to initiating the surgical portion of the case; by the time that the dressings are applied, the tourniquet has been inflated for 20 minutes and can be safely deflated without fear of systemic side effects from the lidocaine. In cases of distal radius fracture requiring CTR, I prefer using two separate approaches—one for the distal radius fixation and a separate CTR rather than one extended incision. Decompression of the carpal tunnel has also been described by releasing the radial insertion of the TCL at the distal aspect of the approach for open

reduction and internal fixation (ORIF) of a distal radius fracture (5,6).

Complications As detailed above, great care must be taken to avoid injury to the palmar cutaneous and recurrent motor branches of the median nerve. Additionally, complete decompression of the median nerve must be confirmed by either direct visualization or palpation; the most common reason for failure of median nerve release is incomplete division of the TCL. P.13 While not a complication, patients with preexisting hand or basal joint arthritis can become more symptomatic following CTR, as their arthritic pain is better perceived following median nerve decompression. Alteration in the mechanical stresses of the trapeziometacarpal or pisotriquetral joints due to division of the attached ligaments also contributes to this increased symptomatology. Preoperative counseling for this is critical to avoid patient dissatisfaction. Pillar pain is a persistent ache at the scar, thenar, and hypothenar eminences following division of the TCL. There is no clear-cut definition of this syndrome, and as such, its incidence is varied in the literature from 19% to 61% (7). The cause of pillar pain is similarly unclear, with various authors pointing to small cutaneous nerves, unmyelinated c-fibers within the TCL, or nerve ending entrapment within postoperative scar. Others feel this is a musculoligamentous phenomenon due to alterations in the carpal arch geometry following release. Treatments have been described with scar massage, stress loading therapy, extracorporeal shock wave therapy (ESWT), or infiltration of local anesthetic. Recently, greater attention has been given to presentation of trigger finger after CTR. The incidence of trigger fingers in the postoperative period following CTR has been reported from 3% to 11%. Diabetic patients are at higher risk of developing trigger digits following CTR (8). Several recent studies have raised the possibility that division of the antebrachial fascia in conjunction with the TCL increases the incidence of trigger fingers, possibly by allowing greater volar translation of the flexor tendons, allowing bowstringing and, as such, altering the angle of entrance at the A1 pulley, increasing forces and friction over these tendons (9,10). In cases where tenosynovectomy or significant mobilization and manipulation of the flexor tendons is performed (such as to access the ligaments of the floor of the carpal tunnel), the potential for peritendinous fibrosis and finger stiffness is significant, and immediate range of motion should be initiated, with consideration for supervision by a hand therapist.

GUYON'S CANAL APPROACH Indications The ulnar nerve may need to be explored or decompressed distally to relieve pressure within Guyon's canal or to explore the nerve following trauma. Knowledge of the anatomy of this area is essential when excising the hook of the hamate for fracture or nonunion. This approach may also be required to identify the ulnar motor nerve fascicle for anterior interosseous nerve (AIN)-to-ulnar motor nerve transfers for severe ulnar neuropathy or very proximal ulnar nerve injury.

Preoperative Preparation Careful inspection for masses or enlargement of the volar ulnar wrist can suggest the presence of a space occupying lesion compressing the nerve. Preoperative imaging is crucial in cases of fracture of the hook of the

hamate. This can be diagnosed with radiographs; however, adequate imaging can be challenging, even with carpal tunnel view radiographs. In those cases, a CT scan is the best imaging modality for fracture. Alternatively, MRI can be useful in evaluating for ganglion cysts or other masses within Guyon's canal. In manual laborers who sustain repetitive impacts or trauma to the volar ulnar wrist, a careful vascular examination is critical to evaluate for ulnar artery thrombosis or aneurysm, which can affect the ulnar nerve as well. This includes Allen's test and Doppler examination.

Technique A standard carpal tunnel incision can be utilized, elevating a large ulnar flap. Alternatively, the skin is incised along the radial aspect of the flexor carpi ulnaris (FCU) and extended distally, zig-zagging across the wrist flexion crease, and extending distally into the palm along the ulnar border of the ring finger to the hook of the hamate. The nerve is identified proximally, where it lies immediately radial and deep to the FCU. The ulnar artery can be identified radial to the nerve. The nerve is then followed from proximal to distal. At the palm, the overlying palmar fascia is released, and the volar carpal ligament (which forms the roof of Guyon's canal) is identified and divided. The nerve is then followed distally as it travels superficial to the flexor retinaculum and between the pisiform and hook of the hamate. Just proximal to the hook of the hamate, the nerve divides into the branch to the hypothenar muscles, the deep motor branch, and the superficial sensory branches. The sensory branch provides innervation to the palmaris brevis muscle and sensation to the small finger and the ulnar half of the ring finger. The deep motor branch arises from the ulnar aspect of the nerve, diving deep to the continuation of the ulnar nerve, and then wraps around the distal aspect of the hook of the hamate as it travels from ulnar to radial across the palm to innervate the interossei, the ulnar two lumbricals, the adductor pollicis, and half the flexor pollicis brevis. P.14

FIGURE 2-5 Zones of compression of the ulnar nerve at Guyon's canal. Compression in zone 1 will cause both motor and sensory changes. Compression in zone 2 will cause isolated motor changes, sparing sensation, whereas zone 3 compression will cause only numbness without loss of motor function. Compression of the ulnar nerve can occur either proximal to the bifurcation of the ulnar nerve or distally and can cause a mixed, pure motor, or pure sensory deficit depending on the portion of the nerve affected by the compression. Zone 1 consists of the ulnar nerve proximal to its bifurcation; compression here results in mixed motor and sensory deficits. Zone 2 is compression of the deep motor branch distal to its bifurcation; sensation is spared when the nerve is compressed here. In situations such as this, it is critical to make sure the deep motor

branch has been specifically identified and fully decompressed during surgery. Compression of the ulnar nerve in zone 3 causes pure sensory deficits, as only the superficial branch is affected, distal to the takeoff of the deep motor branch (Fig. 2-5). After the volar carpal ligament is released and the nerve mobilized, the floor of the canal should be inspected for space occupying lesions such as ganglion cysts, which are commonly encountered.

Pearls and Pitfalls Differentiating ulnar neuropathy at the elbow from ulnar neuropathy at the wrist is critical. Discussion with the patient about activities that bring about symptoms and provocative physical examination findings can greatly aid in making an accurate diagnosis. Diminished sensation of the dorsal ulnar hand is strongly indicative of more proximal nerve compression; however, normal dorsal hand sensation does not rule out proximal ulnar nerve compression. I find that identification of the ulnar nerve is most predictable and straightforward by identifying the nerve in the distal forearm radial to the FCU and then following the nerve distally. To follow the nerve distally to its branch point, a significant amount of dissection of the overlying hypothenar musculature may be needed to both free the nerve and adequately visualize the terminal branches. Identification of the deep motor branch can be difficult, and must be definitively located and decompressed in situations of intrinsic weakness. Failure to do so is a common reason for failed Guyon's decompression. The motor branch should be seen diving deep to the nerve and wrapping around the distal aspect of the hook of the hamate before traversing the palm. Care must be taken to ensure that you are not being fooled by branches to the hypothenar musculature.

WAGNER APPROACH Indications First described by Wagner in 1950, the thumb carpometacarpal (CMC) joint can be exposed from a volar approach. This can be used to reduce and stabilize fractures of the base of the first metacarpal (Bennett's or Rolando's), or for ligament reconstruction with or without trapezium excision for CMC instability or arthritis, respectively. P.15

Technique The incision for the Wagner approach runs along the junction of the palmar and glabrous skin, extending distally between the abductor pollicis longus and the thenar musculature and stopping proximally radial to the FCR. The terminal branches of the superficial radial sensory nerve will cross the radial aspect of the incision, and the palmar cutaneous branch of the median nerve is found at the ulnar aspect of the incision; these must be protected to prevent neuroma formation. After the skin is incised and the cutaneous nerves are identified, the edge of the thenar musculature is identified at the radial aspect of the first metacarpal. The radial border of the fascia is incised, and the muscle fibers are elevated subperiosteally from radial to ulnar off of the joint capsule. By staying deep to the muscle, the overlying neurovascular structures are avoided. Once the joint capsule is exposed, it can be incised and the base of the metacarpal and the trapezium are exposed. At this point, any fracture can be reduced, or the trapezium excised, depending on the surgical goal. If CMC joint stabilization is the desired outcome, the radial half of the FCR can be harvested and utilized for

reconstruction of the intermetacarpal ligament.

Pearls and Pitfalls Care must be taken to avoid injury to the superficial radial sensory nerve branches and the palmar cutaneous branch of the median nerve, which lies just ulnar to the FCR tendon, and is at the proximal ulnar aspect of the incision (Fig. 2-6).

FIGURE 2-6 Incision for the Wagner approach to the thumb CMC joint. Care must be taken to protect the crossing branches of the superficial radial sensory nerve (dotted lines). At the ulnar aspect of the incision, the palmar cutaneous branch of the median nerve will be encountered (see Fig. 2-2). (From Catalano LW, Zlotolow DA, Lafer MP, et al.: Surgical exposures of the hand and wrist. J Am Acad Orthop Surg 2: 48-57, 2012.)

DEEP PALMAR SPACE INFECTIONS There are three potential spaces within the palm that can become infected, resulting in deep space abscesses that require operative drainage (Fig. 2-7). These are the thenar space, the hypothenar space, and the midpalmar space. Infections are usually the result of direct penetrating trauma into the space. However, thenar infections can result from direct extension of pyogenic flexor tenosynovitis of the index finger or deep infiltration of subcutaneous infections. Midpalmar infections can result from proximal extension of long- or ring-finger pyogenic flexor tenosynovitis. It is important to note that often the swelling with these conditions is dorsal, as the ligaments and aponeuroses limit the amount of tissue extension that can occur palmarly. This can make diagnosis of these infections challenging. Advanced imaging including ultrasound or MRI can be helpful in the setting of suspected palmar space infection to identify and localize these abscesses (Table 2-1). P.16

FIGURE 2-7 A: Demonstrates three deep potential spaces within the palm that can be the sites of purulent infection requiring operative drainage: the thenar space, midpalmar space, and hypothenar space. Three deep spaces within the palm can be the sites of purulent infection requiring operative drainage: the thenar space, midpalmar space, and hypothenar space. B: Demonstrates an abscess within the thenar space. C: Shows an abscess within the midpalmar space. (From Stevanovic MV, Sharpe F: Acute infections. In: Wolfe SW, Pederson WC, Hotchkiss RN, et al., eds. Green's operative hand surgery. 6th ed. Philadelphia, PA: Elsevier, 2011.)

TABLE 2-1 Summary of Deep Space Infections Within the Palm Deep Hand Space

Borders

Presentation

Surgical Points

Thenar

Dorsal: adductor pollicis; volar: index flexor tendons; ulnar: vertical midpalmar septum; radial: adductor pollicis insertion at P1 of thumb

Thenar and first webspace swelling, thumb abduction with painful adduction or opposition, pantaloonshaped abscess if involvement of first dorsal webspace through contiguous spread

Palmar, dorsal, or twoincision approaches. Dorsal incision perpendicular to first webspace to minimize webspace contracture; volar incision along thenar crease

Midpalmar/deep palmar

Dorsal: middle and ring finger metacarpals and second and third interossei; volar: flexor tendons and lumbricals; ulnar: hypothenar muscles; radial: vertical midpalmar septum

Loss of normal palmar concavity with marked palm tenderness, painful passive motion of middle and ring fingers; substantial dorsal swelling may be present

Transverse incision in distal palmar crease; curvilinear incision along thenar crease

Hypothenar

Dorsal: small finger

Painful swelling over the

Longitudinal incision

metacarpal; volar: palmar aponeurosis and hypothenar muscle fascia; ulnar: hypothenar musculature; radial: hypothenar septum

hypothenar eminence. Limited palmar swelling beyond this area

along radial border of small finger

Adapted from Osterman M, Draeger R, Stern P: Acute hand infections. J Hand Surg Am 39(8): 16281635, 2014.

Drainage of Thenar Abscesses The thenar space goes from the thenar eminence to the third metacarpal, with a deep boundary of the adductor pollicis fascia. As it travels ulnarly, the thenar space runs deep to the flexor tendons of the index finger, which form the palmar boundary of the area. To approach the abscess in the thenar space, either a palmar or dorsal approach can be utilized (Fig. 2-8). An incision in the dorsum of the first webspace, either transverse or longitudinal, can be used; however, care must be used with a transverse incision, as scar contracture will lead to loss of radial abduction of the thumb. Once the skin is incised, the interval between the first dorsal interosseous and the adductor pollicis is identified and bluntly opened. Purulent material should be encountered at this point. P.17

FIGURE 2-8 Incisions for drainage of a thenar space abscess. A: Palmar incision within the thenar crease. B: Dorsal longitudinal incision for within the first webspace. Transverse incisions should be avoided to prevent webspace contracture. (From Stevanovic MV, Sharpe F. Acute infections. In: Wolfe SW, Hotchkiss RN, Pederson WC, et al., eds. Green's operative hand surgery. 6th ed. Philadelphia, PA: Elsevier, 2011.)

FIGURE 2-9 Incisions for drainage of midpalmar space abscesses. Care must be taken, as the digital nerves and

palmar arch are all in danger during this approach. A: Transverse incision in the distal palmar crease. B: Combined transverse and longitudinal, which allows easy extension into the hypothenar space if necessary. C: Longitudinal approach. (From Stevanovic MV, Sharpe F: Acute infections. In: Wolfe SW, Hotchkiss RN, Pederson WC, et al., eds. Green's operative hand surgery. 6th ed. Philadelphia, PA: Elsevier, 2011.) If a volar approach is preferred, a curvilinear incision can be made in the thenar crease. Care must be taken with deep dissection, as the recurrent motor branch of the median nerve, the digital nerves to the index finger and thumb, the digital arteries to the thumb and index fingers, and the princeps pollicis artery are all within the operative field and in danger of iatrogenic injury. Once the skin is incised, blunt dissection is carried toward the adductor pollicis. The recurrent motor branch is very close, and particular care must be taken at this point. Alternatively, the flexors to the index finger can be identified, and just radial to those tendons is the thenar space. However, the risks of injury to the common digital arteries, common digital nerve, and recurrent motor branch remain the same. A combined volar-dorsal approach can be used, decompressing the adductor pollicis from the volar side and the first dorsal interosseous from dorsally.

Drainage of Midpalmar Abscesses The midpalmar space occurs in the midpalm between the thenar and hypothenar musculature, deep to the flexor tendons of the long, ring, and small fingers, and palmar to the metacarpals and interossei. The midpalmar space is typically approached volarly. The flexor tendons of the ring finger mark the ulnar border of the midpalmar space and are a predictable landmark to find the abscess. Either an oblique incision or an L-shaped incision can be made across the proximal palmar flexion crease and then extended proximally along the radial border of the ring finger (Fig. 2-9). The flexor tendons are identified distally and followed proximally, taking care to find and protect the superficial palmar arch and digital nerves. P.18

Drainage of Hypothenar Abscesses Hypothenar space abscesses are exceedingly rare. The hypothenar space is a small area from the hypothenar septum to the hypothenar musculature. When encountered, the space can be drained through a longitudinal incision along the fourth webspace, from the midpalm to just distal to the wrist flexion crease. The palmar fascia is divided and the hypothenar musculature is identified. Once the fascia of the hypothenar muscles is opened, purulence is encountered and can be irrigated. By staying superficial to this area, neurovascular structures are avoided.

COMPLICATIONS/RESULTS/POSTOPERATIVE MANAGEMENT Please see Chapter 4 for detailed discussion of the complications, results, and postoperative management of deep space infections of the hand.

CONCLUSION The complex anatomy of the hand challenges even the most experienced upper extremity surgeon. Detailed understanding of this anatomy and the surgical approaches outlined here and in other chapters allow for thoughtful and safe exposure for completion of the entire spectrum of hand surgery. The surgeon specializing in hand and upper extremity must be facile with numerous surgical approaches to achieve success in managing the full breadth of pathology encountered.

REFERENCES 1. Sacks JM, Kuo YR, Wollstein R, et al.: Anatomical relationships among the median nerve thenar branch, superficial palmar arch, and transverse carpal ligament. Plast Reconstr Surg 120: 713-718, 2007. 2. Green DP, Morgan JP: Correlation between muscle morphology of the transverse carpal ligament and branching pattern of the motor branch of median nerve. J Hand Surg Am 33: 1505-1511, 2008. 3. Al-Qattan MM: Variations in the course of the thenar motor branch of the median nerve and their relationship to the hypertrophic muscle overlying the transverse carpal ligament. J Hand Surg Am 35: 18201824, 2010. 4. Lourie GM, Gaston RG, Peljovich AE, et al.: Anomalous thenar musculature associated with aberrant median nerve motor branch take-off: an anatomic and clinical study. Duke Orthop J 2: 18-22, 2012. 5. Gwathmey FW, Brunton LM, Pensy RA, et al.: Volar plate osteosynthesis of distal radius fractures with concurrent prophylactic carpal tunnel release using a hybrid flexor carpi radialis approach. J Hand Surg Am 35: 1082-1088, 2010. 6. Pensy RA, Brunton LM, Parks, BG, et al.: Single-incision extensile volar approach to the distal radius and concurrent carpal tunnel release: cadaveric study. J Hand Surg Am 35: 217-222, 2010. 7. Romeo P, D'Agostino MC, Lazzerini A, et al.: Extracorporeal shock wave therapy in pillar pain after carpal tunnel release: a preliminary study. Ultrasound Med Biol 37: 1603-1608, 2011. 8. Grandizio LC, Beck JD, Rutter MR, et al.: The incidence of trigger digit after carpal tunnel release in diabetic and nondiabetic patients. J Hand Surg Am 39: 280-285, 2014. 9. Lee SK, Bae KE, Choy WS: The relationship of trigger finger and flexor tendon volar migration after carpal tunnel release. J Hand Surg (Eur Vol) 39: 694-698, 2014. 10. Karalezli N, Kutahya H, Gulec A, et al.: Transverse carpal ligament and forearm fascia release for the treatment of carpal tunnel syndrome change the entrance angle of flexor tendons to the A1 pulley: the relationship between carpal tunnel surgery and trigger finger occurrence. Sci World J 2013: 630617, 2013.

RECOMMENDED READING Catalano LW, Zlotolow DA, Lafer MP, et al.: Surgical exposures of the hand and wrist. J Am Acad Orthop Surg 2: 48-57, 2012. Franko OI, Abrams RA: Hand infections. Orthop Clin North Am 44: 625-634, 2013. Mackinnon SE, Novak CB: Compression neuropathies. In: Wolfe SW, ed.: Green's operative hand surgery. 6th ed. Philadelphia, PA: Elsevier, 2011: 41-84.

Osterman M, Draeger R, Stern P: Acute hand infections. J Hand Surg Am 39(8): 1628-1635, 2014. Stevanovic MV, Sharpe F: Acute infections. In: Wolfe SW, Pederson WC, Hotchkiss RN, et al., eds. Green's operative hand surgery. 6th ed. Philadelphia, PA: Elsevier, 2011: 41-84.

Chapter 3 Wide Awake Surgery on the Hand Donald Lalonde

INDICATIONS I began practice as a hand surgeon at the end of 1984. I learned in my training years that surgeons needed a tourniquet to perform good hand surgery. We now know that is not true. All that we need to perform even better, less expensive, and safer surgery is to inject lidocaine and epinephrine wherever we are going to dissect (1). We do not need the tourniquet and its associated sedation to get great results. WALANT (wide awake local anesthesia no tourniquet) hand surgery is applicable to 95% of all hand operations. This chapter will enable the surgeon to get started in this approach.

CONTRAINDICATIONS Patients who are not able to tolerate local anesthesia at the dentist Surgeons who do not like to talk to patients during the surgery Operations where a little blood in the field really is a problem (giant cell tumor, vascular malformations, sarcomas, etc.) Mangled hands Excessively long operations such as multiple finger replantations

PREOPERATIVE PREPARATION Office Advice for Patients Explain that their hand operation will be a little like a visit to the dentist for a minor procedure. No preoperative testing or fasting is required as lidocaine and epinephrine are the only administered medications, just like at the dentist. They will be able to get up and leave right after the surgery with no nausea or uncomfortable sequelae or inconveniences of sedation. They will not need to suffer the discomfort of the tourniquet. In the office consultation, we also tell them that putting in the local anesthesia is like baking a cake. After we put it in the oven, we need to give it at least a half an hour to “bake.” We tell them to bring a book or music, as they will have to wait a while after we inject the local anesthesia.

Plan to Inject Two to Three Carpal Tunnels/Trigger Fingers Before You Do the First Case It takes an average of 26 minutes for 1:100,000 epinephrine to reach maximal vasoconstriction (2). Inject two to three patients before taking the first one into the operating room. It only takes an average of 5 minutes to inject local anesthesia for carpal tunnel surgery so that the patient consistently only feels the first poke of a 27-gauge needle (3). We inject them on stretchers in the preoperative holding area, or in the postoperative anesthetic care unit. P.20

The Occasional Patient Will Get Vasovagal So Inject Patients Lying Down

Fainting happens because of a decrease in cerebral blood flow. The body's response forces the patient to lie down by fainting to increase the blood flow with gravity. More patients will faint sitting up than lying down, but they can faint lying down as well. If they do faint, it can look like a seizure with patients going stiff and eyes rolling back. We have all seen this with the occasional cast or dressing change. You will get warning signs before the patient actually faints. The patient will tell you that he or she is not feeling well, that the patient thinks he or she may be sick or will throw up, or that he or she is feeling really hot. When you look at the patient, you may see perioral pallor, or paleness between the eyes, upper nose, and glabella. When you see or hear the warning signs, get more blood to the head with the following five maneuvers, and patients will feel better in less than 5 minutes: Put your hand under the knees and lift them up. Tell the patient to keep the knees and hips flexed to get blood from the thighs to the brain. Take the pillow out from under the head and put it under the feet. Put the head of the stretcher down (Trendelenburg) Keep them in this position for at least 5 to 10 minutes or they will do it again if you sit them up too soon.

Always Warn Patients That They May Get an Epinephrine “Rush” After you inject, always warn patients that they “may feel nervous or shaky” like “they may feel if they drank too much coffee.” Tell them that this is a normal reaction to a little adrenaline in the numbing medicine and that the shaky feeling will go away in half an hour or so if they get it. If patients are not warned about it, fear of the unknown will add to unnecessary concern. They may even walk away feeling that they are allergic to the medication, which they are not.

TECHNIQUE Lidocaine Versus Bupivacaine The author prefers to only use lidocaine with epinephrine. The two main reasons are the following. Firstly, these two medications have an incredibly good safety record in their 65 years of use with no monitoring in dental offices (4). Secondly, although bupivacaine pain relief dose last longer than lidocaine, bupivacaine and ropivacaine are more cardiotoxic than lidocaine. Annoying bupivacaine numbness to touch and pressure lasts twice as long (30 hours) as the pain anesthesia (15 hours) (5). This is why patients sometimes complain that their finger is still numb but it hurts 20 hours after bupivacaine block.

Dosage Limit of Lidocaine With Epinephrine We know that the 7 mg/kg maximum lidocaine with epinephrine rule is extremely safe because 35 mg/kg has been shown to produce safe blood levels of lidocaine in liposuction (6). The author therefore feels comfortable without monitoring unless the patient has severe preexisting cardiac challenges. In these situations, the concentration of epinephrine can be reduced to 1:400,000 or even 1:1,000,000 with good effect (7). High-risk patients can be monitored. In order to stay below 7 mg/kg, the author uses up to 50 mL of 1% lidocaine with 1:100,000 epinephrine for most 70-kg patients. When 50 to 100 mL of volume of local anesthetic is required, the basic 50 mL can be diluted with 50 mL of saline to provide 1/2% lidocaine with 1:200,000 epinephrine. If 100 to 200 mL of volume is required for big forearm cases, add 150 mL of saline to the basic 50 mL of 1% lidocaine with 1:100,000 epinephrine to make 1/4% lidocaine with 1:400,000 epinephrine for good anesthesia and visualization. The only problem with dilute solutions is that the lidocaine and the epinephrine both take a little longer to achieve maximal effect and do not

last quite as long.

PEARLS AND PITFALLS 1% lidocaine with 1:100,000 epinephrine will provide anesthesia and vasoconstriction up to 4 hours after injection. Use a 27-gauge needle and inject slowly. Palpate at least 1 cm of local anesthesia ahead of the sharp needle tip at all times to avoid pain. P.21 Inject the patients outside of the operating room lying down to allow the lidocaine and epinephrine adequate time to numb the skin and nerves, and to permit maximal epinephrine vasoconstriction. It is always better to inject too much local anesthesia than to not inject enough. Always have at least 1 cm of visible or palpable local anesthesia beyond wherever dissection or K-wire insertion will occur. We add bupivacaine if the case is a very big forearm and in complex cases possibly lasting 3 hours or more. The cautery will not be required for most cases. There is no letdown bleeding from the tourniquet because there is no tourniquet. Most bleeders dry up before the skin is closed. Epinephrine is very helpful in patients on anticoagulation. The vasoconstriction decreases the bleeding. There is no letdown bleeding because there is no tourniquet. The dosage and location of local anesthesia injection for other operations than those listed below have been published (8).

Carpal Tunnel Anesthesia Inject 20 mL of 1% lidocaine with 1:100,000 epinephrine and 2.0 mL of 8.4% bicarbonate (9). Inject 2 mL beneath the skin just proximal to the wrist crease and 5 mm ulnar to the median nerve to avoid lacerating it. Inject 8 mL just beneath the radial forearm fascia to numb the median nerve. Inject the remainder under the skin under the hand incision. Aim to get at least 1 cm of palpable, visible local anesthetic on either side of the incision. It takes more than 30 minutes for the median nerve to achieve peak numbness and the same time for epinephrine maximal vasoconstriction to occur as described above. That is why we inject two to three patients before we operate on the first one (Fig. 3-1). Inject 5 mL of 1% lidocaine with 1:100,000 epinephrine and 1.5 mL of 8.4% bicarbonate under the forearm fascia and an additional 5 mL in the fat under the skin incision.

FIGURE 3-1 Local anesthesia for carpal tunnel surgery injection. P.22

Trigger Finger Inject 4 mL of 1% lidocaine with 1:100,000 epinephrine and 0.4 mL of 8.4% bicarbonate in the center of the trigger finger incision just below the fat. There is no need to inject into the sheath. Sheath injections are painful. The local anesthesia will diffuse into the sheath if given enough time to diffuse.

Flexor Tendon Repair or Dupuytren's Palmar Fasciectomy Anesthesia Inject 10 mL of 1% lidocaine with 1:100,000 epinephrine and 1.0 mL of 8.4% bicarbonate in the palm 1 cm proximal to where you plan to dissect (10). Allow the local to numb the nerves for 30 minutes. Then inject another 4 mL into the distal palm and 2 mL into the proximal and middle phalanges. Inject the local just beneath the skin in the fat between the digital nerves. An additional 1 mL can be injected into the proximal midline subcutaneous fat of the distal phalanx if dissection will occur there as in a zone 1 flexor tendon injury (see Figs. 3-2 and 3-3).

FIGURE 3-2 Local anesthesia for flexor tendon repair or Dupuytren's contracture surgery. Inject 10 mL of 1% lidocaine with 1:100,000 epinephrine and 1.0 mL of 8.4% bicarbonate in the palm 1 cm proximal to where you plan to dissect. Wait 30 or more minutes for the distal nerves to get numb and then inject as in Figure 3-3.

FIGURE 3-3 Local anesthesia for flexor tendon repair or Dupuytren's contracture surgery. Now that the distal nerves are numb, inject another 4 mL more distally into the palm and 2 mL into the proximal and middle phalanges. Inject the local just beneath the skin in the fat between the digital nerves. An additional 1 mL can be injected into the proximal midline subcutaneous fat of the distal phalanx if dissection will occur there as in a zone 1 flexor tendon injury.

P.23

Extensor Indicis to Extensor Pollicis Longus Tendon Transfer Inject 30 mL of 1% lidocaine with 1:100,000 epinephrine and 3.0 mL of 8.4% bicarbonate wherever you will dissect in the thumb, index finger base, and hand (11).

Wrist or Forearm Multiple Tendon Lacerations Inject a large volume of dilute local anesthesia (100 to 150 mL of saline + 50 mL of 1% lidocaine with 1:100,000 epinephrine + 5 mL of 8.4% bicarbonate) at least 2 cm beyond any area where you may need to dissect to find the proximal and distal ends of the tendons and nerves. Always make sure to have more instead of not enough local anesthesia to avoid any pain during the surgery. After the skin incision, find the proximal ends of large nerves without grasping them. Inject an additional 10 mL around the proximal nerve stumps.

Trapeziectomy or LRTI Inject 40 mL of 0.5% lidocaine with 1:200,000 epinephrine and 2.0 mL of 8.4% bicarbonate in the radial side of the hand. Imagine that this is an extravascular Bier block, but only where you need it. Start on the proximal part of the incision and inject 10 mL in the subcutaneous fat without moving the needle. Move the needle slowly, and work your way around the trapezium, first volarly and then dorsally. Make sure to bathe the median nerve with local in the process. Inject another 20 mL of the same mixture from proximal to distal over the flexor carpi radialis tendon if you will use this tendon to perform an LRTI. The last injection is 5 mL of the local into the joint after distracting the thumb. After making the skin incision and exposing the joint capsule, inject a further 5 mL into the joint during the surgery.

POSTOPERATIVE MANAGEMENT Complications How to Inject Phentolamine to Reverse Epinephrine Vasoconstriction in the Finger Dogma that epinephrine should never be injected in the finger dominated medical literature from the 1940s until the 2000s. There are still those who believe the myth in 2014. Ample evidence outlined below in bullets has disproved the myth. I have never had to rescue a white finger from epinephrine vasoconstriction, but I have demonstrated phentolamine rescue to many visitors. Surgeons should know how to rescue the finger with phentolamine as a safety precaution. I encourage all surgeons to inject phentolamine at least once so you are comfortable with doing this. Procaine caused the finger deaths blamed on epinephrine before 1950 (12). Procaine became acidic to a pH of 1 when it sat on the shelf in those days before expiry dates were mandated (13). There are publications of thousands of finger injections with no necrosis and no requirement for phentolamine rescue (14,15). There are over 100 cases of high-dose 1:1,000 epinephrine (16,17) accidental injections into fingers. Not one of those fingers injected with a dosage 100 times the concentration of epinephrine that we use clinically for hemostasis actually died, even though many were not treated properly with phentolamine reversal. If 1:1,000 epinephrine does not kill fingers, it is highly unlikely that 1:100,000 will ever kill a finger. For accidental high-dose 1:1,000 epinephrine EpiPen injections, inject 1-mg phentolamine in 1 mL of saline where the EpiPen is present in order to reverse the vasoconstriction (16). The alpha-blocking rescue agent phentolamine reliably reverses epinephrine alpha-receptor vasoconstriction at a dosage of 1 mg in 1 mL of saline in the human finger (level I evidence) (18). If the surgeon is not comfortable with the color of the finger, he can expect phentolamine to reverse the

vasoconstriction within 2 hours of injection. Phentolamine lowers blood pressure at a dosage of 3 mg to 5 mg intravenously (19). If the epinephrine has been injected diffusely in the hand such as in flexor tendon repair or with palmar fasciectomy, inject 1 mg of phentolamine in 5 to 10 mL of saline throughout the wound edges where the epinephrine was injected. P.24

REFERENCES 1. Lalonde DH, Martin A: Epinephrine in local anesthesia in finger and hand surgery: the case for wideawake anesthesia. J Am Acad Orthop Surg 21(8): 443, 2013. 2. McKee DE, Lalonde DH, Thoma A, et al.: Optimal time delay between epinephrine injection and incision to minimize bleeding. Plast Reconstr Surg 31(4): 811, 2013. 3. Lalonde DH: “Hole-in-one” local anesthesia for wide awake carpal tunnel surgery. Plast Reconstr Surg 126(5): 1642-1644, 2010. 4. Jeske AH: Xylocaine: 50 years of clinical service to dentistry. Tex Dent J 115(5): 9-13, 1998. 5. Calder K, Chung B, O'Brien C, et al.: Bupivacaine digital blocks: how long is the pain relief and temperature elevation? Plast Reconstr Surg 131(5): 1098, 2013. 6. Burk RW III, Guzman-Stein G, Vasconez LO: Lidocaine and epinephrine levels in tumescent technique liposuction. Plast Reconstr Surg 97(7): 1379-1384, 1996. 7. Prasetyono TO, Biben JA: One-per-mil tumescent technique for upper extremity surgeries: broadening the indication. J Hand Surg Am 39(1): 3-12, 2014. 8. Lalonde DH, Wong A: Dosage of local anesthesia in wide awake hand surgery. J Hand Surg 38A(10): 2025, 2013. 9. Farhangkhoee H, Lalonde J, Lalonde DH: Teaching medical students and residents how to inject local anesthesia almost painlessly. Can J Plast Surg 20(3): 169, 2012. 10. Lalonde DH, Kozin S: Tendon disorders of the hand. Plast Reconstr Surg 128(1): 1e-14e, 2011. 11. Bezuhly M, Sparkes GL, Higgins A, et al.: Immediate thumb extension following extensor indicis proprius to extensor pollicis longus tendon transfer using the wide awake approach. Plast Reconstr Surg 119(5): 1507, 2007. 12. Thomson CJ, Lalonde DH, Denkler KA: A critical look at the evidence for and against elective epinephrine use in the finger. Plast Reconstr Surg 119(1): 260, 2007. 13. Food and Drug Administration: Warning-procaine solution. JAMA 138: 599, 1948.

14. Lalonde DH, Bell M, Benoit P: A multicenter prospective study of 3,110 consecutive cases of elective epinephrine use in the fingers and hand: the Dalhousie project clinical phase. J Hand Surg 30(5): 1061, 2005. 15. Chowdhry S, Seidenstricker L, Cooney DS, et al.: Do not use epinephrine in digital blocks: myth or truth? Part II. A retrospective review of 1111 cases. Plast Reconstr Surg 126(6): 2031-2034, 2010. 16. Fitzcharles-Bowe C, Denkler KA, Lalonde DH: Finger injection with high-dose (1:1000) epinephrine: does it cause finger necrosis and should it be treated? HAND 2(1): 5, 2007. 17. Muck AE, Bebarta VS, Borys DJ: Six years of epinephrine digital injections: absence of significant local or systemic effects. Ann Emerg Med 56(3): 270-274, 2010. 18. Nodwell T, Lalonde DH: How long does it take phentolamine to reverse adrenaline-induced vasoconstriction in the finger and hand? A prospective randomized blinded study: the Dalhousie project experimental phase Can J Plast Surg 11(4): 187, 2003. 19. Canadian Pharmacists Association Compendium of Pharmaceuticals and Specialties 2000:1405.

Chapter 4 Infections of the Hand Patrick G. Marinello Steven D. Maschke

GENERAL CONSIDERATIONS Encountering infections of the hand is relatively common for most hand surgeons, and these range from relatively benign to devastating. Prompt diagnosis and treatment should be the priority for all infections of the hand. Primary care and/or emergency medicine physicians oftentimes initially see these patients and are challenged with not only making the correct initial diagnosis but also knowing when to refer to a higher level of specialty care. How effective this channel of communication determines the timing and appropriateness of both diagnosis and treatment, which can greatly alter clinical outcomes. The hand surgeon is charged with determining the appropriateness of continued nonoperative care versus the need for operative intervention. The history, physical examination, and knowledge of hand anatomy with its many potential spaces, in conjunction with advanced imaging studies when indicated, guide the surgeon in making the correct diagnosis and determine appropriate management.

FLEXOR TENOSYNOVITIS Indications/Contraindications The volar surface of the hand and fingers frequently comes in contact with potentially harmful objects and environments. The flexor tendons and surrounding sheath are in within millimeters of the skin, making them susceptible to penetration from even minor trauma. Unlike a localized infection in the subcutaneous tissue, inoculation of the flexor tendon sheath provides the bacteria with a path of low resistance to migrate proximally and distally. An innocent-looking puncture wound has the ability to deliver a potentially devastating bacterial organism throughout the tendon sheath of a digit with potential proximal spread into the palm. Although most infections are a result of direct seeding with penetrating trauma, immunocompromised hosts such as patients with poorly controlled diabetes, malnutrition, and HIV are susceptible to hematogenous infections. Healthy patients presenting with flexor tenosynovitis (FTS) without antecedent trauma should have gonococcal infection in the differential diagnosis. In 1943, Kanavel described four cardinal signs of FTS: (a) flexed posture of the finger, (b) fusiform swelling of the finger, (c) tenderness over the entire course of the flexor tendon sheath, and (d) pain on passive extension of the finger (added later). The bacterial infection causes local edema of the tendon, sheath, and surrounding soft tissues. The vincular and intratendinous vascular supply and nutritional support of the tendon become compromised from the elevated pressure within the sheath with the end result being potential tendon necrosis and rupture. Additionally, the gliding mechanism is quickly compromised leading to stiffness and scarring within the tendon sheath. Patients either will present with a known injury with progressive pain and swelling or may not recall an antecedent event prior to the onset of symptoms. A high index of suspicion for FTS is paramount and should prompt urgent consultation and evaluation by a hand specialist. If P.26 early in the disease process, a trial of antibiotics, immobilization, and elevation can be tried for a period of 12 to 24 hours. This should be administered in a hospital observation unit where the patient can be closely monitored. Consultation with an infectious disease specialist can be helpful in selecting appropriate empiric antibiotic

therapy targeted at the most common pathogens and taking hospital-specific antibiotic resistance into account. If no improvement is seen during this short time frame, the patient is urgently brought to the operating room for a proper irrigation and debridement. The long-term sequela of inadequate or delayed treatment of FTS can be devastating, and this condition must be treated aggressively. Functional loss of the affected digits due to stiffness from adhesions, possible tendon necrosis/rupture, as well as spread of the infection more proximally to potential spaces of the hand are all potential consequences of poor management. Severe cases of FTS may lead to digital amputation. All hand surgeons must have a low threshold to perform an expeditious and complete irrigation and debridement in the operating room. Generally, the risk of inaction is much higher for the patient than are the potential complications from surgical intervention.

Pre-Op Planning and Anatomy The clinical history of a penetrating injury or spontaneous swelling in the digit of an immunocompromised patient along with positive Kanavel's signs should be sufficient to make the diagnosis of FTS. All digits need to be examined carefully as more than one finger may be involved. Also, careful evaluation of the palm and wrist for deep space infection or communication between the fingers is critical (Fig. 4-1). Knowledge of the anatomy of the flexor tendon sheath aids in understanding where the infection may spread. In the middle three digits (index, long, and ring finger), the tendon sheaths run from the A1 pulley to the FDP insertion. For the thumb and the little finger, the tendon sheaths extend more proximally to the radial and ulnar bursas, respectively. If the infection penetrates the tendon sheath of the thumb or small finger, it has the potential to spread into the thenar or hypothenar spaces. Communication at the level of the wrist occurs in a potential space between the flexor digitorum profundus tendons and the fascia of the pronator quadratus muscle. Infection in this space, known as Parona's space, leads to a “horseshoe” abscess. Tenderness and swelling in Parona's space should always be evaluated, and when present, surgical decompression proximal to the wrist flexion crease is indicated. Standard orthogonal view x-ray examination of the affected hand is recommended for evaluation of bony involvement or associated foreign bodies. Advanced imaging with an MRI or ultrasound is not indicated when the clinical diagnosis is clear but can be helpful when the diagnosis remains elusive. Laboratory evaluation is helpful. Complete blood count (CBC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) are useful adjuncts to help confirm a diagnosis. However, it is not uncommon for the acute phase reactants to be normal in the early P.27 stages of FTS. Trending laboratory values postoperatively can be useful to determine resolution of infection.

FIGURE 4-1 A: Note the fusiform swelling of this index finger with suppurative FTS. B: Although the involved index finger is “semiflexed,” as described by Kanavel, note that the increased pressure within the tendon sheath

causes this finger to be relatively more extended than the flexion cascade of the adjacent fingers at rest. Antibiotics are a critical part of the treatment for this condition. Unfortunately, in our personal experience, most patients have received antibiotics prior to our consultation, and this may affect our ability to isolate the offending organism and target our antibiotic regimen. If the patient is stable, it is our practice to hold antibiotic therapy until after cultures have been obtained either via aspiration of the tendon sheath or intraoperatively.

Surgical Technique The patient is placed supine on the operating table with the affected upper extremity on a hand table. A wellpadded proximal pneumatic tourniquet is applied on the upper arm. For cases of infection, general anesthesia is typically used at our institution. In the acidic environment of an ongoing infection, local infiltrative anesthetic is not as effective. Surgical loupes magnification and appropriate operating room lighting are beneficial. The upper extremity is then prepped and draped in the usual sterile fashion. A preoperative surgical time-out is performed verifying the correct patient, laterality, anatomic location of the surgery, allergies, preoperative antibiotics (or if they are held), and the presence of necessary equipment and personal. The arm is gravity exsanguinated, and the tourniquet is inflated to 250 mm Hg. No Esmarch bandage is used for exsanguination in cases of infection to diminish risk of spread. We typically hold preoperative antibiotics, and the patient receives them after cultures are obtained. A midaxial incision is made centered on the PIP joint of the affected digit (Fig. 4-2). We incorporate the traumatic wound when appropriate but will not alter our incision to include wounds away from the standard approach. The incision is made on the side of the digit with the least contact. For the index, long, and ring fingers, the incision is typically made on the ulnar side while the incision is made on the radial side for the small finger and thumb. The midaxial incision is extended both proximally and distally as far as needed to allow safe and complete surgical decompression. The neurovascular bundle is identified, dissected, retracted with the palmar flap, and protected (Fig. 4-3). The flexor sheath is identified, and the A3 pulley is incised (Fig. 4-4). Specimens for Gram stain and microbiology can be collected at this time. Careful but deliberate debridement of hypertrophic synovium is completed at this time. If antibiotics were held, after collection of specimens for microbiology, broad-spectrum antibiotic therapy can be initiated. In more severe infections or delayed treatment, larger incisions and multiple windows into the flexor sheath may be required to accomplish adequate debridement. Attention is then turned to the palm. A short Brunner incision at the MP flexion crease of the affected digit is made, and blunt dissection down to the A1 pulley is completed (Fig. 4-5). The A1 pulley is incised, and debridement is accomplished. After both proximal and distal debridement is completed, a no. 5 pediatric feeding tube is passed into the flexor sheath from distal to proximal. Several liters of normal saline are flushed through the sheath with the surgeon ensuring excellent egress. We then pass the feeding tube from proximal to distal and irrigate several more liters of fluid.

FIGURE 4-2 Midaxial surgical approach. The midaxial incision passes through the center of rotation to the PIP and DIP joints. This is approximately 2 to 3 mm dorsal to the midlateral line. The incision should be made on the

side of the digit with the least contact. (Reprinted with permission, Cleveland Clinic Center for Medical Art & Photography © 2015. All Rights Reserved.) P.28

FIGURE 4-3 The plane of dissection in the digit reflects the neurovascular bundle with the palmar skin flap.

FIGURE 4-4 A: The A3 pulley is removed to gain access to the flexor tendons. It is critical that the A2 and A4 pulley remain intact. B: Clinical photo demonstrating that the flexor tendon sheath has been opened between the A2 and A4 pulleys. Note the purulent exudate. (Part A Reprinted with permission, Cleveland Clinic Center for Medical Art & Photography © 2015. All Rights Reserved.) After through decompression and debridement, the tourniquet is deflated and hemostasis is achieved with bipolar cautery. Both wounds are left open. If the severity of the infection warrants, a stay suture can be placed in the proximal incision to facilitate drainage. Prior to leaving the OR, the digit should be inspected for PROM and good capillary refill. We place Penrose drains in both the proximal and distal incisions to facilitate drainage. A bulky sterile dressing is applied as well as a volar splint in the resting position. If there is no clinical response in the initial 24 to 36 hours, a repeat debridement and irrigation with new cultures is undertaken in the operating room. P.29

FIGURE 4-5 A: Short Brunner incision at the MP flexion crease of the affected digit is made, and blunt dissection down to the A1 pulley is completed. B: Clinical image showing irrigation of wound using irrigation tubing from distal to proximal. (Part A Reprinted with permission, Cleveland Clinic Center for Medical Art & Photography © 2015. All Rights Reserved.)

Post-Op Management Admission to an inpatient nursing unit is mandatory after irrigation and debridement for FTS. The patient must strictly elevate the affected extremity, and nursing and physician teams perform frequent neurovascular checks. At our institution, a postoperative consultation with infectious disease is standard protocol. Initially, broadspectrum IV antibiotics (at our institution vancomycin and Zosyn) are started while operative cultures and sensitivities are pending. In consultation with our infectious disease colleagues, we prepare the patient for hospital discharge on either home going IV antibiotics or, depending on the organism, oral antibiotic therapy. Antibiotics are continued until the infection is eradicated and will be influenced by pathogen, severity of infection, and immune status of the patient.

Rehabilitation Starting on the first postoperative day, the dressing is removed, and wound care as well as occupational hand therapy (OT) is initiated. The hand therapist fashions a resting splint, evaluates the wounds, removes the drains, and initiates edema control measures and aggressive range-of-motion exercises. With FTS, the main goal of hand therapy after operative debridement is to regain and maintain as much motion as possible. Active assisted digital range of motion is a critical part of the treatment (Fig. 4-6). Upon discharge, the patient will continue frequent outpatient visits with OT for monitoring and continued progress with wound healing, edema control, and motion. The surgical wounds will heal by secondary intention. Sometimes, scar revision might be indicated, but proper placement of surgical incisions will limit such revision surgery. The psychological effect of open wounds after debridement of FTS can be a barrier for the patient taking an active role in his or her care and rehabilitation. The hand surgeon and hand therapist can be very influential in educating the patients and helping them become champions of their own recovery. P.30

FIGURE 4-6 Active range of motion 5 days after decompression and lavage of suppurative FTS of the long finger.

Outcomes and Complications There is tremendous variability as to the outcomes of FTS. Stiffness of the DIP and PIP joints is common especially when therapy is delayed or the patient is noncompliant. Single organism early infections in a healthy patient with expeditious and appropriate management will often lead to full motion of the digit within 1 to 2 weeks and healing of the surgical scar shortly thereafter. In contrast, delayed presentation of a polymicrobial infection in an immunocompromised host may fail even repeat surgical debridement and ultimately require amputation. Severity of infection, timing, and host factors all convene to affect long-term outcomes. Host factors negatively impacting outcome include age greater than 43, diabetes mellitus, renal failure, and peripheral vascular disease. Clinical factors indicating potential poor outcome include digital ischemia, subcutaneous purulence, and polymicrobial infection. While the treating physician cannot control the patient's health status upon presentation, the surgeon can dictate how quickly definitive care is offered. In the earliest stages of FTS, a short course of nonoperative treatment (elevation and antibiotics) is cautiously indicated, but no more than 12 to 24 hours should elapse before more aggressive surgical treatment is provided. We only consider this course in mild cases with very early symptoms and only 1 or 2 Kanavel's signs. Thorough debridement and irrigation, consultation with an infectious disease colleague, and utilization of hand therapy all play a significant role in maximizing long-term outcomes.

DEEP SPACE INFECTIONS General Considerations Deep space infections of the hand are uncommon, and the clinical presentation and diagnosis can be challenging. Such infections arise from proximal spread of FTS or from primary inoculation of the hand through penetrating trauma. The hand has three potential deep spaces: the thenar space, the hypothenar space, and the midpalmar space (Fig. 4-7). Clinical presentation will often demonstrate

P.31 dramatic swelling of the entire hand most evident dorsally as the tight volar fascia limits palmar swelling. All patients will have exquisite tenderness to palpation over the involved space.

FIGURE 4-7 Medical illustration of the hypothenar, thenar, and midpalmar potential spaces. Also depicted are the flexor tendon sheaths. (Reprinted with permission, Cleveland Clinic Center for Medical Art & Photography © 2015. All Rights Reserved.)

FIGURE 4-8 Clinical picture depicting midpalmar space infection with loss of palmar concavity. Thenar space infections are most common. The thenar eminence will be tense and quite tender to palpation. The thumb will be held in an abducted posture, and attempted active or passive adduction will lead to significant pain. Frequently, the purulence will track over the adductor pollicis and first dorsal interossei muscles leading to a “collar button” abscess of the first web space. Midpalmar space infections are less common and occur via penetrating trauma or proximal migration from FTS of the long and ring fingers. Significant swelling of the entire hand is present with loss of the normal concavity of the palm assuming a convex appearance (Fig. 4-8). We have seen median nerve compromise from infection in the

midpalmar space. P.32 Hypothenar infections are uncommon. They almost always occur via direct penetrating injury and will demonstrate less overall swelling of the hand. Tenderness to palpation directly over the hypothenar space and a high index of suspicion lead to appropriate diagnosis. Advanced imaging is often beneficial to help arrive at the correct diagnosis and direct surgical management. The patients we have managed have presented with dramatic swelling of the entire hand and pain limiting their ability to localize the area of most significant pain. MRI is our preferred method of evaluation, but if timely access is not available, ultrasound has shown benefit in localization and determining extent of infection. There is not a role for nonoperative management of these infections. Once the correct diagnosis is obtained, urgent operative management must be undertaken.

Surgical Technique The surgical management of these infections is straightforward. We prefer to use volar approaches and design our incisions to limit potential scar contracture. Most importantly, we avoid extending our incisions distally into the web spaces. If our ability to decompress the abscess dorsally is limited, we prefer to make a separate dorsal approach. The surgical approaches also place the neurovascular structures at risk and require careful dissection and surgical technique. The infections lie deep in the hand with the dorsal boundary being the metacarpals and intrinsic musculature. Again, careful evaluation for dorsal tracking is mandatory, and if limited by the volar approach, a separate dorsal exposure is prudent. After complete irrigation and debridement, the wounds are left open or loosely approximated with surgical drains or packing in place (Fig. 4-9). As with FTS, immediate postoperative care consists of fabrication of a resting splint, wound care and soaks, edema control, and motion. Antibiotics are managed in conjunction with our infectious disease colleagues and continued based on clinical response.

FIGURE 4-9 A: Clinical photograph of palmar deep space infection from penetrating trauma. B: Extensile volar surgical approach. C: Loosely approximated closure with surgical drain. P.33

Outcomes As with FTS, outcome is dependent on host factors and time to surgical treatment. Due to the deeper nature of the infection, it can make the clinical diagnosis more challenging, and delayed treatment is not uncommon. Stiffness and contractures are common following deep space infections but can be minimized by appropriate surgical management and implementing an active motion therapy program. We believe active motion is critical to encourage tendon gliding and joint motion and limit long-term complications. The unique anatomy of the deep spaces of the hand can lead to complications secondary to treatment. Iatrogenic nerve and vascular injuries occur secondary to altered anatomy and poor technique. Scar contracture is not uncommon but can be avoided by thoughtful placement of surgical incisions. With prompt diagnosis and appropriate surgical management, the vast majority of patients achieve full recovery and return to their previous occupation.

HIGH-PRESSURE INJECTION Presentation and Indications for Surgery High-pressure injection injuries of the hand are relatively rare but potentially devastating injuries to the hand. The patient is almost always a male industrial worker utilizing high-pressure tools. The injury is commonly found in the nondominant hand and occurs accidentally when misusing

P.34 or cleaning a malfunctioning piece of equipment. The real danger of these injuries is that the initial external injury is typically not impressive. The patient as well as inexperienced healthcare providers can be fooled by the benign appearance of the injury and may not initiate prompt tertiary referral.

FIGURE 4-10 A: Clinical photograph of puncture wound from highpressure injection injury from oil-based paint. B,C: AP and lateral radiographs demonstrating foreign material. The pressure associated with the injury greatly impacts the rate of digital amputation. For pressure less than 1,000 psi, the amputation rate is approximately 20%, while pressure greater than 1,000 psi is associated with an amputation rate above 40%. Overall amputation rate for high-pressure injuries is approximately 30%. Organic solvents (paint, thinners, gasoline, diesel fuel) have much higher (approaching 40%) amputation rates, while injuries due to water or air have a much better outcome. Fingers are more likely to be amputated than injuries to the thumb and palm. The key to successful outcome following these injuries is ensuring prompt treatment. Delayed debridement beyond 6 hours from injury leads to an increased incidence of amputation. The exception to this is high-pressure injuries from air or water. The amputation rate for these materials in the literature is 0%, and they can be treated nonoperatively. Infection was found in approximately 40% of injuries and was polymicrobial in nature, and broadspectrum IV antibiotic coverage is crucial. Some have advocated steroid used in the acute setting. Theoretically, the steroids can help modulate the inflammatory response. The use of this adjunctive therapy is controversial, and no definitive consensus exists on its risks and benefits.

Radiographs are helpful and aid in defining the proximal extent of the injected material. We have encountered patients with high-pressure injections at the distal tip of the finger with proximal tracking into the midforearm (Fig. 4-10).

Surgical Technique As previously described, general anesthesia, standard supine positioning with a hand table, and gravity exsanguinated tourniquet are utilized. In our opinion, the timing of surgery is most critical. Unlike surgery for FTS, the surgical approach must provide wide exposure to allow access for complete removal of the injected material. When designing our surgical incisions, we prefer midaxial incisions with extension into the palm and forearm as indicated (Fig. 4-11). In our opinion, Brunertype exposures increase the risk of flap necrosis and long-term complications. After raising full-thickness flaps, the neurovascular structures are carefully dissected and protected. The injected material is then meticulously removed with a combination of rongeur, curette, and/or any other instrument that is effective. Removal is often painstakingly slow and requires patience and perseverance. Thorough irrigation with normal saline is undertaken. The tourniquet is deflated, and capillary refill is confirmed. Management of the skin is case dependent. In relatively minor cases, we will close the skin and initiate occupational therapy. In more advanced cases, we will leave the wounds open and pack with saline-soaked gauze. In these cases, a planned return to the operating room 36 to 48 hours later is undertaken for repeat evaluation, further debridement, and loose approximation of the skin. Postoperative management is similar to that for FTS and deep space infections. We continue antibiotics for 7 to 10 days and personally do not favor the use of corticosteroids. Hand therapy is critical for wound care, edema control, and regaining motion.

FIGURE 4-11 A,B: Clinic photograph of midaxial approach for debridement of material from high-pressure injection injury from oil-based paint. P.35

Management Considerations For high-pressure injuries, organic solvents provide the most challenging conditions due to the nature and tissue toxicity of the material. Debridement within 6 hours is the goal. Understanding the nature of the injury (timing, material, and pressure involved) will allow the surgeon to appropriately inform the patient regarding risks and long-term expectations. Hogan and Ruland reviewed 435 cases of high-pressure injection injury to the hand with an overall amputation rate of 30%. Organic solvents, pressure above 1,000 psi, and delayed surgical debridement (greater than 6 hours) all negatively impacted the rate of amputation. An amputation rate of 88% was found for those injuries secondary to organic solvents and no operative intervention. These results need to be discussed with patients upon presentation setting the stage for appropriate expectations. Pain and stiffness are not uncommon following injury.

CONCLUSIONS Prompt diagnosis and treatment of infections and high-pressure injuries in the hand are essential to maximize the clinical outcomes and patient recovery. A low threshold should be maintained for operative intervention, as irrigation and debridement is the mainstay of treatment. Collaboration with colleagues in infectious disease and occupational therapy is invaluable to the long-term success and return of function in these challenging cases.

RECOMMENDED READING Abrams RA, Botte MJ: Hand infections: treatment recommendations for specific types. J Am Acad Orthop Surg 4(4): 219-230, 1996. Draeger RW, Bynum DK Jr: Flexor tendon sheath infections of the hand. J Am Acad Orthop Surg 20(6): 373382, 2012. Hogan CJ, Ruland RT: High-pressure injection injuries to the upper extremity: a review of the literature. J Orthop Trauma 20(7): 503-511, 2006. Pappou IP, Deal DN: High-pressure injection injuries. J Hand Surg 37(11): 2404-2407, 2012. Rosenwasser MP, Wei DH: High-pressure injection injuries to the hand. J Am Acad Orthop Surg 22(1): 3845, 2014. Schnall SB, Vu-Rose T, Holtom PD, et al.: Tissue pressures in pyogenic flexor tenosynovitis of the finger. J Bone Joint Surg [Br] 78(5): 793-795, 1996. Sharma KS, Rao K, Hobson MI: Space of parona infections: experience in management and outcomes in a regional hand centre. J Plast Reconstr Aesthet Surg 66(7): 968-972, 2013.

Chapter 5 Operative Treatment of Metacarpal Fractures Lance A. Rettig Thomas J. Graham

INDICATIONS/CONTRAINDICATIONS The majority of isolated metacarpal fractures are effectively managed with closed reduction and splint immobilization. However, a subset of metacarpal shaft or neck fractures cannot be reduced by closed means or are unstable after reduction. For these fractures, operative treatment is a consideration or a requirement. Simple extra-articular diaphyseal metacarpal fractures may be amenable to transcutaneous pin fixation or intramedullary stabilization. If the fracture is not reducible by closed reduction, or if pin stabilization fails to maintain adequate stability, open treatment is required. Indications for open reduction and internal fixation include open fractures, injury to multiple metacarpals, intra-articular displacement, and fractures associated with significant soft-tissue injury or segmental bone loss. The decision to consider operative stabilization may be influenced by age and hand dominance along with vocational and avocational demands. Few true contraindications exist to operative fixation of metacarpal fractures. Age is a consideration in young patients with open physis or elderly with severe osteopenia.

PREOPERATIVE PLANNING Physical examination should focus on assessing rotation, shortening, and angulation of the digit resulting from the metacarpal fracture. The majority of metacarpal fractures can be adequately evaluated with plain film radiographs. Anteroposterior, lateral, and oblique hand x-rays are important to help characterize the fracture and define the metacarpal anatomy. A Brewerton view may be helpful in the evaluation of the fractures of the metacarpal head. Semipronated or semisupinated oblique P.38 projections are of value when assessing injuries of the border rays, especially possible carpometacarpal (CMC) fracture-dislocations. CT imaging of the hand may be beneficial in these instances to evaluate for concomitant hamate injury or subluxation of the CMC joint.

SURGICAL TECHNIQUE The operating room setup is standard for surgery of the hand. The patient is supine with the affected extremity on a hand table. A padded pneumatic tourniquet encircles the proximal brachium. The anesthesia choices range from local (wrist block) and regional (including axillary and Bier block) to general endotracheal anesthesia regardless of closed versus open treatment. Prior to prepping and draping, it may be helpful to perform a fluoroscopic examination of the metacarpal injury. Traction and manipulation of the involved ray under the fluoroscan can provide information about fracture reduction and detail about the pathoanatomy. This step is important in determining whether the fracture can be managed with closed reduction and pinning or by open methods. Further defining the fracture in this manner may also assist in placement of the skin incision when open treatment is indicated. When an open approach is required, skin incisions are positioned slightly offset from the metacarpal to reduce the risk of scarring of the extensor mechanism (Fig. 5-1). Following the skin incision, blunt dissection is undertaken to identify branches of the superficial radial and ulnar nerves. Extreme caution should be undertaken when approaching the most ulnar ray, particularly the more proximal aspect of the metacarpal. Careful handling of the dorsal ulnar sensory nerve is critical in the approach to the small finger metacarpal. This is especially

important when performing intramedullary pinning (Fig. 5-2). Exposure of the fracture is undertaken by incising the periosteum longitudinally. Subperiosteal dissection will help define the plane of the injury. In cases of long oblique diaphyseal or comminuted segments, extreme care should be undertaken to avoid additional compromise of the bone integrity. The fracture site is inspected and irrigated to ensure that no intervening soft-tissue structures are blocking reduction. This step is particularly important in cases of delayed treatment when scar or granulation tissue may impede anatomic restoration. Maintenance of exposure is achieved with the use of self-retaining retractors and Hohmann- or Bennett-type instruments. Fracture reduction is undertaken by a combination of longitudinal traction and derotation. In certain cases, realignment of the metacarpal may be facilitated by performing a Jahss maneuver. By positioning the MCP joint in a flexed posture, the proximal phalanx can be used as a lever to assist with addressing rotational deformity. A sharp tenaculum will assist with reduction and provisionally stabilize the fracture. Once anatomic reduction has been achieved, Kirschner wires may also be utilized to temporarily stabilize the metacarpal. Clinical assessment of digital alignment is assessed by passively positioning the digits into flexion to ensure there is no digital overlap. Implant selection is largely based on the plane and configuration of the fracture. Although each fracture has a unique personality, there are some basic tenets to fixation of these injuries that exist. P.39 Implant choices include lag screw fixation alone or combined with plate stabilization. Plate fixation may be used in compression or as a neutralization device. Other options not discussed in this chapter include wiring techniques or external fixation.

FIGURE 5-1 Longitudinal incisions are offset from the fractured metacarpal in an effort to spare the extensor tendon(s) from excessive scarring with contiguous skin and bone while preserving sufficient fracture exposure.

FIGURE 5-2 The diagram illustrates the course of the dorsal sensory branch of the ulnar nerve and its proximity in the approach utilized for small finger metacarpal bouquet pinning. A retractor is placed deep to the extensor carpi ulnaris and is retracted radially. With indications established, the choice of operative fixation becomes the next consideration. For the purposes of this chapter, fracture treatment will be divided into closed treatment with pin stabilization and open reduction internal fixation.

CLOSED TREATMENT WITH PIN STABILIZATION A myriad of configurations and techniques have been described for closed reduction and pinning of metacarpal fractures. These have included cross-pinning, transverse pinning to an adjacent intact metacarpal, intramedullary pinning, or combination of these patterns. Collateral recess pinning and bouquet pinning are described because of the technical challenge inherent in these fixation methods and their unique utility.

Collateral Recess Pinning This method is often utilized for reducible transverse diaphyseal fractures and metacarpal neck injuries. Fracture extension into the collateral recess and degree of comminution may preclude the use of this technique in certain cases. Provisional closed reduction of the fracture is performed. The metacarpophalangeal (MCP) joint of the fractured metacarpal is flexed to 90 degrees. A 0.045-inch or 0.062-inch Kirschner pin is manually positioned percutaneously onto the radial or ulnar collateral recess while maintaining the flexed posture of the MCP joint. The initial pin placement is completed by feel or stereognosis (Fig. 5-3). Fluoroscopy is used to confirm appropriate placement at the deepest concavity of the collateral recess. A lateral view is also completed to evaluate the position of the wire in the sagittal plane. Assessing initial pin position is critical to minimize the number of additional passes of the wire required to achieve fixation. Once the pin has been manually positioned in the collateral recess, the driver is positioned over the wire. The pin is captured at its flex point nearest the leading end of the Kirschner wire (Fig. 5-4A). The pin is then advanced into the shoulder of the metacarpal P.40 P.41 while the appropriate angle is established. One must consider the relationship of the pin to the metacarpal in

both the sagittal and frontal planes prior to intramedullary placement of the wire. The Kirschner pin needs be positioned collinear with the long axis of the metacarpal within the sagittal plane (Fig. 5-4B). Alignment in the coronal plane requires that the pin be placed at an angle so that the leading edge of the wire crosses the fracture site within the confines of the intramedullary canal.

FIGURE 5-3 A: The Kirschner pin is manually placed into the collateral recess with the metacarpophalangeal joint of the fractured metacarpal flexed to 90 degrees. B: The smooth wire is placed at the deepest concavity of the collateral recess.

FIGURE 5-4 A: After manual positioning of the Kirschner wire onto the collateral recess, the pin is captured at the flex point nearing the leading edge of the smooth pin. The metacarpophalangeal joint is maintained in a flexed position. B: Prior to pin advancement, the wire is positioned collinear with the long axis of the metacarpal shaft.

Fluoroscopy is repeated to check the overall alignment of the pin and its insertion site. The fracture site is visualized to check reduction. Once anatomic alignment has been confirmed, the wire is advanced across the fracture, down the medullary canal, and into the proximal cortex. Ideally, proximal fixation is obtained with cortical purchase in the metacarpal base or metaphysis (opposite cortex from initiation point) (Fig. 5-5). Crossing the CMC joint to allow the pin to reside in the distal carpus is typically not problematic. Maintenance of fracture reduction and pin placement is confirmed with intraoperative imaging. A second pin of the same caliber is placed in the opposite collateral recess using the previously discussed technique. Often, the two pins obtain a crossed configuration proximal to the fracture site. With the pins in place, the stability of the fracture fixation and the rotational alignment are assessed. The pins are bent at 90 degrees and cut (Fig. 5-6). A bulky dressing and protective splint are applied.

FIGURE 5-5 Ideally, the collateral recess pins occupy a crossed configuration within the medullary canal with purchase in the proximal metacarpal metaphysis. P.42

FIGURE 5-6 Kirschner wires are bent and cut after fluoroscopic confirmation of the collateral recess pins.

FIGURE 5-7 The length and location of the typical incision for fifth metacarpal bouquet pinning is shown.

Bouquet Pinning An alternative method of pin fixation may be considered when treating distal third metacarpal fractures involving the border digits. In metacarpal neck fractures that are reducible but unstable, “bouquet pinning” or intramedullary stabilization can be utilized. The incision is distant from the distal metacarpal fracture site. It is made at the glabrous border over the tubercle of insertion of the extensor carpi ulnaris (ECU) tendon (Fig. 5-7). The length of the incision may vary with patient size, but 2.0 cm to 3.0 cm is standard. Care must be exercised to avoid damage to smaller arborizations of the dorsal sensory branch of the ulnar nerve. Typically, the main sensory branch crosses the midaxis, an imaginary line drawn between the ulnar styloid and the ECU tubercle, about halfway between these structures. Thus, it is conceivable that handling of the nerve will be necessary, even through such a limited incision (see Fig. 5-2). P.43

Because a relatively volar starting point is desired, the ECU tendon should be reflected dorsally, but splitting the insertion as it fans to a broader area is acceptable. There is a small area of prominence, a “shoulder,” at the ulnar metacarpal base that presents a convexity relative to the juxtaarticular margin at the CMC joint and the remainder of the metaphysis; it is at this area, or just proximal to it, that the intramedullary canal should be entered (Fig. 5-8A, B). Use of fluoroscopy to P.44 locate the entry site is recommended to avoid potential pitfalls (Fig. 5-8C). If the cortical window is made too proximal, intra-articular fracture into the CMC joint could result. More commonly, the entry is too distal, which makes introduction of the pin arduous as it has difficulty by passing the narrow isthmus.

FIGURE 5-8 A: The entrance site is located just proximal to the convexity at the base of the small finger metacarpal. B: A sagittal plane view of the fifth metacarpal shows the close proximity of the cortical window to the juxta-articular margin. The length of the portal measures approximately 4 to 6 mm. C: With the use of intraoperative image intensification, the starting point can be localized with a hypodermic needle. Cortical perforation can be accomplished with hand tools or power drills. After initial opening of the canal, the

entry site is best enlarged with curettes. Because the direction of the tools entering the canal influences the tract taken by the fixation pins, the introitus should be machined with the most acute angle possible (Fig. 5-9). Although the integrity of the metacarpal base must be maintained, the portal of entry must be large enough to accommodate the desired number of pins (usually three). The size of the hole is approximately 4 to 6 mm in diameter. The portal is made ovoid to minimize the chance for fracture propagation due to this stress riser. While the skin edges and ECU are retracted, access to the canal should be unrestricted, and attention is turned to preparation of the pins for insertion. To minimize tourniquet time, the pins can be prepared ahead of time, with some consideration of the individual patient's anatomy. Most commonly, a 0.045-inch smooth wire is the implant of choice. Occasionally, a 0.062-inch wire may be required for extremely large hands. The 0.035-inch wire can be used for gracile metacarpals or for secondary or supplemental pins after instrumenting the canal with a 0.045inch wire. The next three steps are critical to successful bouquet pinning: 1. Cut the sharp tips off the pins. Leaving the sharp tip may create a second perforation in the cortex. The additional cortical defect often captures the pin on subsequent passes, complicating the procedure. 2. Bend the pin throughout its length. The pin is contoured with a gentle bend along its entire body. The best way to describe the bend is to liken it to a catenary or a telephone wire between two points. Minor adjustments are made to conform to the individual canal morphology, but the typical prebend as described will suffice for the majority of pins. P.45 3. Deflect the tip of the pin at its leading end. The creation of a bend allows the pin to “bounce off” the endosteum of the canal and gives the pin direction. The secondary bend is performed in the same plane as the primary arc, but is placed about 3 mm from the end of the pin to be introduced into the canal end that will eventually reside distal to the fracture in the metacarpal head (Fig. 5-10).

FIGURE 5-9 A: The canal is entered with a drill or awl. The starting point and direction of cortical perforation are both critical elements for eventual success. B: It is helpful to create a conduit in the metaphyseal bone of the metacarpal base that influences the direction of the pin.

FIGURE 5-10 A: The pin adjacent to the hand is prebent for the specific reasons described in the text. B: A secondary bend is fashioned in the same plane as the primary arc, placed 3 mm from the end of the leading edge of the pin. The pin is best controlled with two large needle holders that can be used to advance the implant and reorient it inside the canal. This will allow for controlled progression of the pin and optimize its position in the metacarpal head. The position of the terminal bend is inferred from the greater arc of the pin, directing the tangential contact of the pin with the endosteum and determining that the “bouquet” can reliably be accomplished by paying attention to the three-dimensional characteristics of the bent pin. There are two useful techniques that can facilitate the procedure. First, using one needle holder to advance the pin, while the second is grasping nearer the insertion site, serves to “stiffen” the implant and permit easier passage (Fig. 5-11). Second, radial deviation of the hand (for fifth metacarpal fractures, or ulnar deviation for second metacarpal fractures) makes pin introduction more facile. The senior author has reluctantly used as few as two pins to stabilize a fifth metacarpal head fracture in a small patient with a gracile canal. However, we advocate the use of at least three pins in most circumstances. The maximum number we have used is six pins (a combination of 0.035-inch and 0.045-inch wires in a large male patient). Viewing the fracture under biplanar imaging intensification to ensure reduction is crucial. Before passing the leading edge of the pin across the fracture site, a manual reduction maneuver must be performed (Fig. 5-12). Perforation of the pin through the (dorsal) cortex of the shaft or through the fracture site must be guarded against. If these difficulties occur, partial or complete removal of the pin from the canal and reorientation by utilizing the two needle holders will usually rectify the problem. At times, two or more pins may act as a “track” for subsequent pin insertions; typically, this is beneficial, yet this arrangement can also preclude placement of the pin in the desired location. P.46

FIGURE 5-11 The passage of the pin within the metacarpal canal is facilitated by the surgeon positioning the two needle holders as depicted in the illustration.

FIGURE 5-12 A reduction maneuver is performed before passing the wire across the fracture site. P.47

FIGURE 5-13 The wire ends naturally recess into the metacarpal canal and can be further secured by gentle bone tamp use. Once the fracture has been reduced and the pins placed, the ends are cut as close to the canal as possible (Fig. 5-13). The pins can be advanced slightly with a bone tamp, providing there is enough room at the distal aspect of the metacarpal head. The proximal ends of the pins reside in the canal and are sometimes locked into position by the proximal lip of the cortical perforation. The soft tissues are closed over the cortical defect. The skin is closed with a nylon suture. A bulky dressing is applied to the level of the proximal interphalangeal joint (PIP) that restricts MCP joint motion only slightly.

OPEN TREATMENT Distal Third Metacarpal Fractures Fractures of the distal third metacarpal are divided into the following categories: Intracapsular fractures, with special emphasis on coronal splitting fractures of the metacarpal head True neck fractures that involve the region from the juxta-articular margin to the metadiaphysis, including the collateral recesses Distal shaft fractures

Intracapsular Fractures Intra-articular fractures often occur within the index ray. Several different fracture patterns exist for intracapsular fractures of the metacarpal including two-part, comminuted, ligament avulsion and concomitant metacarpal neck fractures. In the case of head splitting fractures, there are three types of patterns: coronal, sagittal, and oblique. These two-part fractures are often amenable to open reduction and screw fixation. The joint is approached by splitting the extensor mechanism. A longitudinal skin incision is performed just ulnar to the metacarpal phalangeal joint. The extensor tendon is split longitudinally to expose the dorsal capsule of the MCP joint (Fig. 5-14). Fullthickness radial and ulnar capsular flaps are developed to expose the articular surface. Meticulous handling of the articular fracture is critical to preserve vascularity and avoid iatrogenic injury. The fracture may be mobilized and reduced with the use of a dental pick. After anatomic reduction is achieved, the fracture is stabilized with a micro- or mini headless compression screw. If the size of fragment allows, an additional derotational K-wire can be placed during screw fixation. The headless device is advanced until the proximal portion of the screw is just deep to the articular surface (Fig. 5-15).

P.48

FIGURE 5-14 After exposure of the extensor mechanism, the central tendon is split longitudinally over the MCP joint. The extensor hood and sagittal bands are mobilized and the dorsal capsule incised.

FIGURE 5-15 A: The radiographs demonstrate displaced metacarpal head fracture involving the ling finger. B,C: A dorsal approach to the metacarpal head was undertaken with subsequent reduction and internal fixation with a microheadless screw. Postreduction radiographs demonstrate anatomic reduction with the headless screw placed deep to the articular surface. P.49

FIGURE 5-15 (Continued)

Neck Fractures Surgical stabilization options for the metacarpal neck include closed reduction and percutaneous pinning, open reduction with pinning or internal fixation, and intramedullary pinning. When determining the type of fixation device in fractures of the metacarpal neck, it is critical to assess the pathoanatomy of the fracture. Specifically, fracture extension into the collateral recess may complicate the surgeon's ability to maintain anatomic reduction with conventional pinning. Highly comminuted or significantly displaced fractures may not be amenable to closed reduction and stabilization. Open reduction with minicondylar plate stabilization may be required in these injuries. Associated soft-tissue injuries may also determine the type of fixation.

Distal Third/Middle Third Fractures In distal third and middle third shaft fractures, the type of fixation is determined by the fracture configuration (transverse, oblique, and spiral fractures). The condition of the soft-tissue envelope and level of comminution may influence the method of stabilization.

Transverse Fractures Transversely oriented fractures of the distal third metacarpal shaft that are reducible but unstable, intramedullary fixation, or bouquet pinning may be utilized. In the case where a transversely oriented metacarpal shaft fracture is proximal to the metadiaphyseal junction, collateral recess pinning may be indicated (see Fig. 5-6). If the diaphyseal fracture is unreducible, open reduction and dorsal plate fixation is recommended. Most commonly, a 2.0 or 2.4 straight plate is utilized. Two screws are placed distal to the fracture in neutral. Proximal to the fracture, the drill is placed eccentrically away from the fracture within the hole of the plate. Advancement of the screw provides a compression force across the fracture site. Four or six screws are placed to stabilize the fracture. Four to six cortices proximal and distal to the fracture site are desirable. In cases of transverse fractures involving the metadiaphyseal junction, an L- or T-shaped plate may be required. The plate is placed in compression as described in Figure 5-16. P.50

FIGURE 5-16 A reduced transverse metacarpal shaft fracture is diagrammed. A: Two drill holes are centered in the plate holes distal to the fracture. The miniplate has a graduated bend of approximately 5 degrees centered at the middle of the miniplate with no acute bend or buckling of the plate, especially not at the level of the holes in the plate. B: Two neutral (centered in the plate holes and applying no force to the plate) miniscrews are inserted distal to the fracture. A drill hole is placed eccentrically away from the fracture in the miniplate hole just proximal to the fracture. C: A miniscrew is inserted into the eccentrically placed drill hole. D: The screw head engages the plate hole as the miniscrew is tightened, causing the fracture to compress as the plate moves proximally. E: A drill hole is centered in the remaining proximal plate hole. F: A neutral miniscrew is inserted, completing the fixation. The sequence of miniscrew insertion is numbered. G,H: AP and lateral x-rays demonstrate a displaced unstable fourth metacarpal shaft fracture with shortening and angulation in both the AP and lateral planes. There was also rotational malalignment of the ring finger with digital flexion. P.51

FIGURE 5-16 (Continued) I: The fracture has been exposed. J,K: A curette and rongeur are used to remove clot and granulation tissue at the fracture site. L: The fracture is reduced by manipulation and instrumentation using bone reduction forceps. Rotational alignment is checked with the fingers flexed into a fist. M: A four-hole slightly bent (5 degrees) straight miniplate is centered over the fracture. N: The distal fracture fragment is initially secured with a neutral miniscrew inserted into the plate hole just distal to the fracture. An eccentric hole is drilled through the miniplate hole just proximal to the fracture. P.52

FIGURE 5-16 (Continued) O: A second miniscrew is inserted into the eccentric drill hole. Engagement of the screw head with the plate hole has compressed the fracture. P: Two neutral miniscrews are inserted into the remaining plate holes to complete the construct. Q,R: Postoperative anteroposterior and lateral x-rays demonstrate stable anatomic fracture fixation. (A through F from Heim U, Pfeiffer KM, eds. Internal Fixation of Small Fractures, 3rd ed. New York: Springer Verlag, 1988:54-55. Figs. 31 and 32.)

Long Oblique Diaphyseal Fractures Oblique or spiral fractures while sometimes reducible are often unstable owing to the configuration particularly in the border digits. The length of the spiral fracture will often determine the type of implant utilized. In cases where the length of the fracture is greater than twice the diameter of the metacarpal shaft, interfragmentary screw fixation can be utilized. Two or more 2.0 or 2.4 lag screws are often satisfactory to stabilize this type of fracture. Once the fracture has been reduced and provisionally stabilized, inspection of the fracture length will help determine the location and potential number of screws for stabilization. In general, two screws are utilized in fracture lengths that are twice the diameter. When fracture length exceeds three times the diameter, then fixation may be achieved with three screws. Interfragmentary screws may be placed in compression or neutralization. By definition, compression screws are placed perpendicular to the fracture in lag fashion and provide the greatest compressive force. A neutralization screw is positioned perpendicular to the long axis of the diaphysis and provides resistance to shear forces. In cases of long spiral fractures, it is usually possible to place a lag screw that is both perpendicular to the fracture and long axis of the bone. If it is not possible to place a screw in this orientation, attempts are made to position both a screw in compression and neutralization mode to improve stability of fixation. Countersinking is performed when possible to improve load characteristics. The technique of lag screw fixation is detailed in Figure 5-17. P.53

FIGURE 5-17 A,B: A displaced unstable long spiral fracture of the third metacarpal shaft. C: The fracture is reduced and secured with a pointed reduction forceps. A gliding hole is drilled in the near cortex with a 2.7-mm drill. A drill guide is used to protect adjacent soft tissues and to prevent skating of the drill on the bone. D: The opposite end of a double-ended drill guide corresponds to the 2.7-mm diameter of the gliding hole. The drill guide is inserted in the gliding hole in the near cortex, and a 2.0-mm core hole is drilled concentrically through the opposite cortex. E: The countersink is rotated to fashion an area in the proximal half of the dorsal cortex to correspond to the screw head. F: A depth gauge determines the length of the screw hole. P.54

FIGURE 5-17 (Continued) G: A 2.7-mm tap is used to thread the core hole of the distal cortex. A tap sleeve is used to protect adjacent soft tissues. This step is omitted when self-tapping screws are inserted. H: A miniscrew is inserted. As it glides through the proximal hole, the head of the miniscrew engages the proximal cortex, creating compression at the fracture site as the screw threads purchase the distal cortex (lag screw effect). Note that a compression miniscrew is inserted perpendicular to the fracture. I: A second miniscrew is inserted using a similar technique to the first but in a plane perpendicular to the long axis of the bone, satisfying the need for maximum neutralization of shearing forces. J,K: AP and lateral x-rays demonstrate an anatomic reduction of the fracture secured with two minilag screws.

Sagittal Short Oblique Diaphyseal Fracture In cases of spiral fractures whose length is less than twice the diameter of the bone, interfragmentary screw fixation alone will not provide sufficient fixation. Stability of short oblique metacarpal fractures is best achieved with a single interfragmentary screw and a neutralizing dorsal plate. Following anatomic reduction and provisional stabilization, a lag screw is placed in compression. The screw is positioned away from the dorsal cortex to allow plate stabilization. A five- or seven-hole plate (if possible) is then contoured to the dorsal cortex. The center most hole is positioned over the lag screw. This hole is left empty. Attempts are made to obtain at least two screws with bicortical purchase proximal and distal to the fracture site. Depending on the location of the fracture within the diaphysis, a T-plate may be indicated to obtain satisfactory purchase.

P.55

Proximal Third Fractures Proximal fractures of the metacarpal can be divided into two categories: shaft and intra-articular. Once again, in cases of proximal shaft fractures, they are divided into short oblique, spiral, and transverse. The short oblique or transversely oriented fracture may be treated with closed reduction and collateral recess pinning versus open reduction internal fixation when operative indications are present. Metacarpal shaft fractures treated with closed reduction percutaneous pinning often require passage of the pin across the CMC joint (Fig. 5-18). In cases of oblique/spiral or intra-articular fractures, open reduction and internal P.56 fixation may be performed with an L- or T-plate. This type of plate configuration allows for adequate fixation proximal to the fracture site. Plates with locking options are beneficial when attempting to improve the quality of fixation within the proximal metaphyseal bone in periarticular fractures.

FIGURE 5-18 A: After closed reduction of the small finger metacarpal base fracture, the fragment was stabilized with a 0.045 smooth wire placed from the radial collateral recess. B: A second pin was placed from the ulnar collateral recess across the CMC joint for added stability. C,D: Stabilization of the long finger metacarpal shaft fracture was achieved with collateral recess pinning. Both the radial and ulnar recess wires were advanced across the CMC joint to secure fixation of the long finger metacarpal diaphyseal fracture.

POSTOPERATIVE MANAGEMENT

Collateral Recess Pinning Metacarpal fixation with collateral recess pinning requires approximately 4 weeks of immobilization in a safeposition splint; in most patients, the PIP joint can be free. Because pin stability and pin tract infections are concerns, appropriate immobilization is required when the pins are indwelling. This is accomplished with rigid immobilization for 3 to 4 weeks followed by interval splinting. Careful motion of adjacent digits and even other digital segments of the operated ray can be initiated. Active and active-assisted motion of the DIP, PIP, and MCP joints commences following pin removal at approximately 1 month post-op. The patient is maintained in an orthosis for an additional 2 weeks. With clinical and radiographic signs of healing, the splint is gradually weaned.

Closed Pinning Following bouquet pinning, the patient is maintained in the soft postsurgical dressing for 1 to 2 weeks. Most patients should expect to have enough pain control to initiate mobilization within the bulky dressing during the first week. Active and active-assisted motion commences within the first 7 to 10 days. Sutures are removed at 10 to 14 days, at which time radiographs are obtained. A removable, short arm, safeposition orthosis is furnished to immobilize the hand during the intervals between exercise sessions. Passive motion is initiated after clinical and radiographic healing is achieved. Strengthening is started after satisfactory motion has been achieved along with radiographic healing. Interval splinting with intermittent range of motion is permitted.

Open Reduction In most cases, lag screw fixation or plate stabilization provides a rigid construct permitting early motion and return to activities. Three to five days following open reduction and internal fixation, patients begin active range of motion with protective splinting. The surgical hand is placed positioned into a forearm-based splint that includes the MCP joint. Aggressive efforts are made to restore full flexion of the MCP joint. Light passive motion of the interphalangeal joints is initiated within 2 to 3 weeks after the procedure. Active motion takes place at 3 to 4 weeks post-op. As healing permits, light strengthening exercises are started between 4 and 6 weeks.

RESULTS Collateral Recess Pinning Because the patient can pursue a program of interphalangeal motion and no direct manipulation of these levels is undertaken, the PIP and DIP joints usually recover motion rapidly. A program of blocked flexion and intrinsic stretching can assist in accelerating the functional return. The MCP joints are initially limited in motion. The most frequent presentation is that of extension lag, which sometimes exceeds 30 degrees. This result is likely due to the influence of the fracture callus and the extensor penetration by the pins. Because the collateral ligaments are held at their greatest length during pin insertion, the lag is probably not related to capsuloligamentous contracture. The extensor has relatively little excursion through the composite motion arc (compared to the flexors), which may help to explain this phenomenon. Flexion usually returns rapidly and heralds greater functional capability, such as grasping, which is key for strengthening tasks. As long as the fracture is believed to be clinically united, the pursuit of MCP motion can be aggressive. In addition to night splinting in extension and any active motion, intrinsic stretching and even dynamic splinting is reasonable. Eventually, buddy taping to an adjacent normal digit can assist in promoting a greater arc of motion. Return to contact activities is safe if comfort and reasonable function has been demonstrated. This is typically

between the 6th and 8th postoperative weeks or the 3rd to 4th week after the pins have been discontinued. Our experience with collateral recess pinning now exceeds 100 patients. To date, we have not experienced any major complications, and healing of the fractures has been seen in all patients, including multiplefracture cases. P.57 Pin tract infections have occurred in less than 5% of patients and have been treated with pin removal, local wound care, and oral antibiotics. We have not seen any cases of septic arthritis. Although it is difficult to categorize patients on whom this technique has been employed, we can state that no significant motion limitation, strength compromise, or repeat surgery has been associated with the subgroup of patients treated for closed fractures. Because we employ this technique for even more complex injuries, including open fractures and combined injuries (skin, bone, tendon, nerve, and vessel), revision, or salvage, surgery has been employed in some cases to maximize results. We have not found any untoward sequelae related to this fixation method.

Bouquet Pinning The ability of bouquet pinning to reduce fractures, stabilize them rigidly, and permit early motion is unparalleled. The opportunity to operate away from the joints of the osteoarticular column of the hand, where there is such a premium on flexibility, is tremendously attractive. We have now employed the bouquet-pinning technique in over 100 patients. Over 90 of those cases have involved the fifth metacarpal. To date, there have been no significant complications. We have noted no iatrogenic nerve injuries, hardware migrations, loss of reduction, infections, or need for repeat surgery. Even in cases of complex fracture patterns of open injuries (six cases), this technique has proven complication-free. One of the most impressive observations about this tool is the abundant fracture healing response that accompanies pin placement. Often, early callus is seen on radiographs at initial postoperative visits between 10 and 14 days after surgery. Most patients already have recovered between 50% and 75% of their composite motion at the MCP, PIP, and DIP joints by that first visit because the bulky dressing has not restricted their motion. The only clinical issue we have encountered is a lingering (6- to 8-week) soreness at the incision site. This appears to be related to the difficulty with which the initial access the canal was gained. This predictable sequela responds to aggressive scar massage and initial pad protection if early contact is required by the patient's vocation or avocation. We have not encountered pin migration or need for pin removal because we place the proximal pin ends within the metacarpal shell.

Open Treatment The majority of patients undergoing open reduction internal fixation for simple metacarpal fractures do well. Union rates for these injuries are greater than 95%. Greater than 75% of patients achieve 220 degrees of total active motion. Outcomes following metacarpal fixation are influenced by the degree of comminution and severity of soft-tissue injury. Reoperation rates approach 15% in open metacarpal injuries. Nonunion and infection rates are increased in open injuries compared to metacarpal fixation in hand injuries with an intact soft-tissue envelope.

COMPLICATIONS Closed Pinning Bouquet intramedullary pinning of metacarpal fractures yields few postoperative complications. Reported

complications are dorsal ulnar sensory nerve embarrassment, reflex sympathetic dystrophy, infection, and discomfort at the base of the operated metacarpal, yet these untoward occurrences are infrequent. Injury to the dorsal ulnar sensory nerve can be avoided with careful attention to surgical dissection and awareness of local anatomy. The few reported cases of reflex sympathetic dystrophy have been associated with crush injuries and multiple metacarpal fractures. Some complications can occur as a result of technical error. Penetration of the wire through the MCP joint, extensor tendon rupture secondary to proximal protrusion of the wire, and secondary displacement of the fracture after early wire removal have been reported. In our practice, hardware removal is not advocated. Although rare for closed pinning of metacarpal fractures, nonunion has been reported.

Open Treatment Despite aggressive measures to mobilize the operated digit early, stiffness is still one of the most common sequelae. Capsular adhesions and scarring of the extensor mechanism following operative plate fixation in a simple metacarpal fracture occur in approximately 15% to 20% of cases. P.58 This percentage increases in cases of open or crush injuries. Reoperation may require MCP joint capsulectomy and extensor tendon tenolysis. Postoperative infections average 0.5% in closed injuries and approach 11% with open fractures. Rarely, bone grafting is required for delayed or nonunion in closed metacarpal injuries.

RECOMMENDED READING Blazar PE, Leven D: Intramedullary nail fixation for metacarpal fractures. Hand Clin 26(3): 321-325, 2010. Botte MJ, Davis JL, Rose BA, et al.: Complications of smooth pin fixation of fractures and dislocations in the hand and wrist. Clin Orthop Relat Res 276: 194-201, 1992. Duncan RW, Freeland AE, Jabaley ME, et al.: Open hand fractures: an analysis of the recovery of active motion and of complications. J Hand Surg Am 18(3): 387-394, 1993. Foucher G: Bouquet osteosynthesis in metacarpal neck fractures. A series of 66 patients. J Hand Surg 20(3 Pt 2): S86-S90, 1995. Freeland AE, Jabeley ME: Open reduction internal fixation: metacarpal fractures. In: Strickland JW, ed. Master techniques in orthopaedic surgery: The hand. Philadelphia, PA: Lippincott-Raven, 1988: 3-33. Fusetti C, Meyer H, Borisch N, et al.: Complications of plate fixation in metacarpal fractures. J Trauma 52(3): 535-539, 2002. Henry MH: Fractures of the proximal phalanx and metacarpals in the hand: preferred methods of stabilization. J Am Acad Orthop Surg 16(10): 586-595, 2008. Kozin SH, Thoder JJ, Lieberman G: Operative treatment of metacarpal and phalangeal shaft fractures. J Acad Orthop Surg 8: 111-121, 2000.

McLain RF, Steyers C, Stoddard M: Infections in open fractures of the hand. J Hand Surg Am 16(1): 108112, 1991. Ozer K, Gillani S, Williams A, et al.: Comparison of intramedullary nailing versus plate-screw fixation of extraarticular metacarpal fractures. J Hand Surg Am 33(10): 1724-1731, 2008. Page SM, Stern PJ: Complications and range of motion following plate fixation of metacarpal and phalangeal fractures. J Hand Surg Am 23(5): 827-832, 1998. Rettig LA, Graham TJ: Closed pinning and bouquet pinning of fractures of the metacarpals. In: Strickland JW, Graham TJ, eds. Master techniques in orthopaedic surgery: The hand. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins, 2005: 27-46. Ring D: Malunion and nonunion of the metacarpals and phalanges. Instr Course Lect 55: 121-128, 2006. Tan JS, Foo AT, Chew WC, et al.: Articularly placed interfragmentary screw fixation of difficult condylar fractures of the hand. J Hand Surg Am 36(4): 604-609, 2011. Yaffe MA, Saucedo JM, Kalainov DM. Non-locked and locked plating technology for hand fractures. J Hand Surg Am 36(12): 2052-2055, 2011.

Chapter 6 Operative Fixation of Juxta-Articular, Intracapsular, and Diaphyseal Fractures of the Phalanges and Interphalangeal Joints David E. Ruchelsman Matthew I. Leibman Mark R. Belsky Thomas J. Graham The phalanges are short tubular bones, but tend to exhibit similar fracture patterns to the long tubular bones of the skeleton. Phalangeal fractures are subject to displacement, angulation, and malrotation due to forces exhibited by the traversing flexor and extensor tendons and collateral ligaments at juxta-articular locations. The metaphyseal and articular fractures are subject to compressive forces and joint impaction, and diastasis can be challenging to reconstruct. The etiology of digital stiffness following operative fixation of unstable phalangeal diaphyseal, juxta-articular, and intra-articular fractures may be multifactorial. Malreduction with resultant softtissue imbalances, extensor/flexor tendon adhesions, and capsular contractures may be minimized with meticulous operative technique and initiation of early functional rehabilitation. Conceptually, we divide phalangeal fractures into articular and nonarticular injuries involving the proximal, middle, and distal phalanges. Extra-articular fractures include fractures of the neck, shaft, or base. Articular fractures include unicondylar fractures; comminuted intra-articular fractures (i.e., bicondylar fractures); dorsal, volar, or lateral base fractures; pilon fractures and fracture-dislocations; and diaphyseal fractures with articular extension.

EXTRA-ARTICULAR PHALANGEAL FRACTURES Diaphyseal Phalangeal Fractures Phalangeal fractures may be transverse, oblique, spiral, or comminuted/multifragmentary. The latter are usually associated with significant soft-tissue injury even if the overlying skin envelope is intact. Spiral and oblique fractures are more common in the proximal phalanx diaphysis, and transverse fractures tend to be more common in the middle phalanx and proximal third of the proximal phalanx. P.60 Transverse proximal phalangeal fractures tend to collapse into an apex volar angulation, with the proximal metaphysis flexed by the interosseous insertion. The remainder of the phalanx then collapses into extension due to the longitudinal pull of the extrinsic extensor. Angulation of middle phalangeal fractures is generally apex dorsal as the sublimis insertion along the distal fragment draws the distal fragment into flexion. Management of phalangeal fractures depends on the following factors: displacement, fracture geometry, softtissue injury, and patient characteristics and requirements. Treatment should be tailored to the individual taking into consideration fracture characteristics. Oblique and spiral fractures are prone to shortening and malrotation when treated nonoperatively. Periarticular oblique fractures may involve the collateral recess or subcondylar fossa and effect function. Comminuted fractures are prone to shortening, soft-tissue adhesions, delayed healing, and stiffness. Indications/Contraindications Greater than 10 degrees of malangulation in the coronal or sagittal plane

Malrotation Shortening Open fractures Combined injuries Preoperative Preparation Regional versus local anesthesia Mini-C arm Kirschner wires (0.045 inch, 0.035 inch) Modular plate/screws (1.5 mm, 1.3 mm, 1.1 mm)

Techniques Closed Reduction and Percutaneous Pinning Percutaneous K-wire fixation is the most common method of operative stabilization of unstable proximal and middle phalangeal shaft fractures once satisfactory reduction has been achieved. Care is taken to try and avoid violation of the extensor hood, central extensor tendon, and neurovascular bundles. Early range of motion following percutaneous K-wire fixation is often limited as skin motion at the pin sites may lead to superficial and/or deep pin site infections. K-wire placement depends on the fracture pattern, configuration, and bone quality. Proximal metaphyseal fractures at the base of the proximal phalanx usually demonstrate dorsal cortical comminution with apex volar angulation. Multiple adjacent fingers can fracture in this fashion in the elderly osteoporotic individual after a fall. Imaging of the phalangeal base is difficult especially after an acute injury. While these fractures are reducible with digital flexion, they are inherently unstable. These fractures may also extend proximally and involve the articular surface. Antegrade crossed K-wires beginning at the periphery of the articular margin are often used to stabilize these fractures (Figs. 6-1 and 6-2). The metacarpophalangeal (MCP) joint is flexed maximally and the distal fracture fragment of the proximal phalanx reduced to the metaphyseal segment. Alternatively, these fractures can be stabilized with a longitudinal wire passed antegrade through the metacarpal head into the medullary canal of the proximal phalanx (1). Additional pins may be inserted to provide rotational stability especially in more distal fractures. Each technique has inherent advantages and disadvantages. Patients are counseled regarding the potential for extensor and/or flexor tendon adhesions at the level of the metaphyseal fracture corresponding to the A2 pulley. At times, tenolysis of the flexor system and/or MCP/proximal interphalangeal joint (PIP) contracture releases are needed following osseous union. Oblique and spiral fractures may be stabilized with two or more K-wires passed percutaneously perpendicular to the fracture plane. If one elects percutaneous fixation of these rotationally unstable fractures, it is imperative to use fluoroscopy to ensure that the wires truly engage in a bicortical fashion and in the plane perpendicular to the plane of the fracture (Fig. 6-3). Transverse or short oblique wires can be fixed with crossed K-wires. As crossing K-wires tend to distract the fracture, manual compression must be applied to the digit at the time of insertion of the second wire. The fracture is usually immobilized for approximately 3 weeks, and the wires are then removed followed by protected motion with buddy taping. P.61

FIGURE 6-1 A: Proximal phalangeal metaphyseal fracture with articular extension. Apex volar angulation is seen. B: Closed reduction and percutaneous crossed K-wire fixation is achieved. C: Osseous union with anatomic articular and metadiaphyseal alignment.

FIGURE 6-2 A: Proximal phalangeal metadiaphyseal fracture with rotational and sagittal plane deformity. B: Closed reduction and percutaneous crossed K-wire fixation is achieved. C: Osseous union with anatomic articular and metadiaphyseal alignment. Full motion was achieved at latest follow-up. P.62

FIGURE 6-3 A: Rotationally unstable middle phalanx oblique diaphyseal fracture. B: Closed reduction and percutaneous parallel K-wires perpendicular to the plane of the fracture. Postoperatively, a DIP joint tip protector splint is utilized while early PIP joint motion is initiated. Pearls and Pitfalls Avoidance of an intra-articular starting point with antegrade crossed K-wire fixation of proximal phalangeal metaphyseal/diaphyseal fractures. Use of intrinsic plus casts/splints to minimize MCP joint stiffness and contracture. Avoidance of K-wires placed through the collateral recess of the interphalangeal joints to minimize collateral ligament contracture. Newer fixation systems with self-tapping mini-screws allow for percutaneous screw fixation through small incisions after reduction. Percutaneous screw fixation achieves interfragmentary compression and may allow for earlier motion. Use of local anesthetic and active motion in the early postoperative period (i.e., 4 to 6 weeks) may facilitate “closed tenolysis” and yield increases active composite flexion. Postoperative Management Initiation of mobilization is based on clinical tenderness as early clinical union precedes radiographic union. Following clinical union (typically 4 to 6 weeks postoperatively), a digital block may be performed in the office if there is early postoperative digital stiffness followed by active digital motion to attempt “closed tenolysis” of early adhesions and facilitate recovery of digital motion. Sagittal plane malunion may result in clinical pseudo-claw deformity and extensor imbalance with resultant extensor lag. Open Reduction and Internal Fixation Open reduction is indicated for irreducible phalangeal fractures, open fractures, and combined injuries. Stable internal fixation facilitates early postoperative functional rehabilitation. A dorsal curvilinear or lateral/midaxial incision is most frequently utilized for proximal phalangeal exposure. Several deep surgical intervals exist. For diaphyseal fractures of the proximal phalanx, the interval between the central extensor tendon and lateral band may be incised, or the extensor may be mobilized together with the ipsilateral conjoined lateral band (Fig. 6-4). For metadiaphyseal fractures, a unilateral intrinsic resection of the lateral band and oblique fibers of the

P.63 MCP joint facilitates mobilization and reflection of the central extensor tendon in a supraperiosteal fashion (2) (Fig. 6-5). The periosteum is incised along the obliquity of the fracture to allow for anatomic reduction and internal fixation. This exposure is especially useful for lateral plate fixation of unstable proximal phalanx fractures. Lateral plate application minimizes interference with extensor tendon excursion. Furthermore, biomechanical analyses (3,4) have suggested that mid-lateral plate positioning may have superior biomechanical properties. Alternatively, the extensor may be split in its midline for wide exposure of the fracture.

FIGURE 6-4 A: For diaphyseal fractures of the proximal phalanx, a dorsal curvilinear incision is used followed by mobilization of the central extensor in a supraperiosteal fashion together with the ipsilateral conjoined lateral band (star). B: Following mobilization of the extensor, the fracture is exposed and anatomically reduced along cortical keys, followed by interfragmentary screws. C: Anatomic reduction and osseous union are achieved. A small residual extensor lag at the PIP joint is expected. Fractures of the distal third of the proximal phalanx can be exposed in a limited fashion for screw placement without incising the extensor mechanism. The lateral band can be retracted dorsally following division of the transverse retinacular ligament as is performed for fixation of unicondylar fractures (as outlined below). Independent of deep exposure selected, the entire length of the fracture must be exposed, especially with spiral fractures, prior to reduction. The apices must be visualized to confirm anatomic reduction and restoration of length and rotation. Once the fracture is provisionally reduced with bone reduction forceps or K-wires, tenodesis maneuver is performed to confirm restoration of the digital cascade. The fracture-specific fixation construct is then selected. Interfragmentary screws enhance stability compared to K-wires and wire loop fixation constructs. Screws alone are best indicated for the stabilization of oblique and spiral fractures when the length of the fracture is more than twice the diameter of the bone to allow placement

P.64 of at least two screws (Figs. 6-6 and 6-7). Obtaining bicortical fixation is more imperative than is true lag compression (5). When planning screw placement, care should be taken to stay a minimum of 2 screw diameters away from the fracture margin to prevent cortical failure. Generally, 1.3-mm and 1.5-mm screws are used depending on fragment size and comminution (Fig. 6-8).

FIGURE 6-5 A: Unstable and displaced ring finger proximal phalangeal metaphyseal fracture. Following elevation of a full-thickness subcutaneous flap from the peritenon of the central extensor tendon, the conjoined lateral band on the side of plate application is excised to facilitate fracture site exposure and reduction. B: Ulnar (lateral) plate application following excision of the ulnar conjoined lateral band and fracture reduction. A periarticular locking plate is selected based on the metaphyseal location of the primary fracture line. C: Final radiographs demonstrate osseous union. Plate fixation is indicated when K-wire or lag screw fixation is inadequate as in fractures with comminution, articular fractures with extension into the shaft, and for reconstruction of nonunions and malunions. Additionally, there are some fractures such as transverse fractures of the midshaft that are amenable to compression plating. Plate stabilization is used in multifragmentary and comminuted phalangeal fractures. Complications of plate fixation are related to their use in more complex cases and open fractures P.65 rather than the technique itself (6). Plates can be placed dorsally (Fig. 6-9) or laterally (Fig. 6-10) based on fracture pattern and direction of displacement. While extensor irritation is less likely with lateral plate placement, the latter is also more technically demanding due to the limited area of bone surface available. Generally a

minimum of four cortices should be fixed on either side of the fracture.

FIGURE 6-6 A: Long oblique proximal phalangeal fracture with shortening and disruption of the subcondylar fossa. B: ORIF with two interfragmentary screws. C: Final clinical outcome demonstrate full composite digital flexion and extension. Several recent technical advances in plate and screw design have facilitated the application of plates to the phalanges and may reduce complications. New plates are lower profile with varying shapes, thicknesses, and recessed screw heads (Fig. 6-11). A particularly important advance is locking screw technology that allows the screw to thread into the plate hole for added stability. Locking plates are particularly useful for osteopenic bone, for comminuted fractures, and for periarticular fractures where the locking screws buttress the articular surface (7). External fixators are used for highly comminuted diaphyseal fractures precluding stable internal fixation, combined injuries with bone and soft-tissue loss, and management of infected nonunions necessitating staged reconstruction. External fixation avoids additional soft-tissue dissection and fragment devascularization. Various unilateral fixators are available and multidirectional clamps allow fine tuning of fracture reduction following pin placement. Reduction of displaced/malangulated distal phalangeal diaphyseal and tuft fractures is considered in the setting of significant sagittal plane deformity in order to repair the lacerated overlying nail matrix. The nail plate is removed and the nail matrix is repaired followed reduction and K-wire fixation of the distal phalanx fracture. Transarticular fixation is often performed to avoid early loosening of the K-wire(s). P.66

FIGURE 6-7 A: Rotationally unstable proximal phalangeal diaphyseal fracture. B,C: Extensor tendon mobilization is facilitated with release of the ipsilateral lateral band proximally and the transverse retinacular ligament distally, which facilitates exposure of the apices of the long oblique fracture. D: ORIF with interfragmentary screws yields union and full functional arc of motion.

FIGURE 6-8 A: Multifragmentary ring finger proximal phalangeal fracture. B: Appropriately sized interfragmentary screws were used to secure fixation of this multiplanar fracture. P.67

FIGURE 6-9 A: Ring finger proximal phalangeal fracture secondary to crush injury. B: Given the location of the wound and the underlying combined extensor tendon injury, dorsal plating was performed. Ultimately, extensor tenolysis, hardware removal, and PIP joint capsulectomy were required.

FIGURE 6-10 A: Malangulated comminuted index finger proximal phalangeal fracture. B: Following excision of the radial conjoined lateral band, fracture reduction and stabilization was performed using a hybrid fixation construct. A single interfragmentary screw secured an intercalary butterfly fragment, followed by lateral application of a 1.5-mm periarticular locking plate based on the comminuted metaphyseal nature of this fracture.

FIGURE 6-11 A: Multifragmentary middle phalangeal periarticular fracture. B: Following fracture exposure on each side of the terminal extensor tendon, dual column plating was performed using low profile anatomically precontoured variable angle locking plates. P.68 Pearls and Pitfalls Unilateral intrinsic resection of the lateral band and oblique fibers of the MCP joint allows for lateral plating of proximal phalangeal fractures and minimizes postoperative extensor tendon adhesions.

Division of the ipsilateral transverse retinacular ligament facilitates lateral band mobilization for distal diaphyseal fractures of the proximal phalanx and unicondylar fractures. Repair of the periosteum over implants may minimize postoperative adhesions. Interfragmentary screws are used when the length of the fracture is more than twice the diameter of the bone to allow placement of at least two screws. Visualize occult nondisplaced fracture lines that may preclude screw fixation. Use of locking plate designs for comminuted and periarticular fractures. Postoperative Management Hand-based intrinsic plus splints are utilized. Early functional rehabilitation following stable internal fixation is initiated within the first postoperative week. Extensor adhesions are minimized by encouraging early active motion, functional splinting, and edema control. Reverse blocking splints and exercises are utilized to minimize extensor lag at the PIP joint. LMB splinting is used to address PIP flexion contractures. Static and dynamic splints may be needed to address adhesions and joint contractures following clinical union. Phalangeal Neck Fractures Isolated subcondylar fractures of the neck of the phalanx are almost exclusively seen in children with the majority occurring in toddlers. The mechanism of injury is usually from crush injury. Al-Qattan (8) classified pediatric phalangeal neck fractures into nondisplaced, minimally displaced with partial contact of the bony fragments, and completely displaced. The distal condylar segment can be displaced dorsally or volarly, and there may also axial plane deformity (i.e., malrotation). Indications/Contraindications Closed reduction and percutaneous wire fixation is recommended for all displaced fracture of the phalangeal neck. Nondisplaced neck fractures are followed with serial radiographs to confirm maintenance of reduction. Preoperative Preparation General anesthesia versus local anesthesia with sedation Mini-C arm Kirschner wires (0.045 inch, 0.035 inch, 0.028 inch) Technique Following closed reduction, the fracture is often stabilized with oblique K-wires (Fig. 6-12) placed in a retrograde fashion. At times for middle phalangeal neck fractures, a P.69 transarticular longitudinal K-wire may be used (Fig. 6-13). Limited open incisions may be necessary to facilitate anatomic reduction prior to percutaneous pinning. Because of the narrow area of contact and lack of any softtissue attachment to the distal fragment, these fractures are inherently unstable and displaced fractures cannot always be reduced with closed techniques alone (Fig. 6-14).

FIGURE 6-12 A: Widely displaced and angulated phalangeal neck fracture. B: Closed reduction and percutaneous pinning with crossed K-wire technique. C: Well-healed phalangeal neck fracture at 6 weeks.

FIGURE 6-13 Transarticular longitudinal K-wire fixation of displaced middle phalangeal neck fracture.

FIGURE 6-14 A: Skeletally immature patient with severe crush injury and complex combined injury. The skeletal injury included an open distal phalanx transphyseal separation with an open comminuted displaced middle phalangeal neck fracture. The phalangeal neck fracture was extremely unstable secondary to comminution and severe soft-tissue injury. B: Clinical photos demonstrate a volar-radial softtissue degloving injury off of the flexor sheath and the dorsal-ulnar extension of the soft-tissue injury. The digital arteries were lacerated requiring revascularization, and the digital nerves contused. C: Reduction was obtained using the remaining cortical keys along the dorsal ulnar neck (forceps). Bone grafting of the radial metaphyseal void was performed. The avulsed terminal extensor was repaired. P.70 Pearls and Pitfalls Non/minimally displaced phalangeal neck fractures are easily overlooked in the emergency department when suboptimal orthogonal radiographs are obtained. A true lateral radiograph is required to appreciate more subtle phalangeal neck fractures. In this view, displacement of the capital fragment or condylar malrotation is best visualized. Intraoperatively, care is taken to ensure that obliquely placed K-wires cross in the coronal and sagittal planes proximal to the primary fracture line to maximize rotational stability. A true lateral view is required to assess reduction of the subcondylar fossa. Waters and colleagues (9) have proposed a treatment algorithm for skeletally immature phalangeal neck fractures that present in a delayed fashion. Subacute fractures with residual tenderness at the fracture site may be amendable to percutaneous osteoclasis, reduction and fixation. Open treatment is associated with increased risk of osteonecrosis. Neck fractures with delayed presentation, minimal residual fracture site tenderness, and satisfactory PIP motion are potentially better managed with observation and delayed subcondylar recession if a block to flexion ensues (Fig. 6-15).

FIGURE 6-15 A: Skeletally immature patient with a proximal phalangeal neck nascent malunion. Delayed presentation at 1 month postinjury. Sagittal plane displacement and abundant callus are noted at presentation. Expectant management was selected because there was minimal fracture site tenderness at presentation, no malrotation, and satisfactory early active (60 degrees) and passive (90 degrees) flexion. B: Remodeling noted at the phalangeal neck at 1 year following initial fracture. C: Clinical exam demonstrated full motion at latest followup. Postoperative Management In children, a cast is used until K-wire removal, typically between 3 and 4 weeks postoperatively. In adults, a PIP or distal interphalangeal joint (DIP) joint splint can be used.

Complications Sagittal plane malunion may result in loss of motion due to an altered arc of motion. Dorsal displacement leads to an osseous flexion block at the subcondylar fossa. Displacement in the coronal plane leads to angular deformity of the digit. As the injury is distant to the growth plate, it is believed that remodeling potential is limited. There is recent clinical P.71 evidence that remodeling in the sagittal plane may occur even in older patient who remains skeletally immature (10,11,12). Remodeling in the coronal and axial planes is less predictable. Pin site infection Joint stiffness Chondrolysis and osteonecrosis of the capital segment

ARTICULAR PHALANGEAL FRACTURES Condylar Fractures Indications/Contraindications Condylar fractures affect the younger population and are usually sport-related (13). Fracture orientations are determined by force vectors and the position of the digit at the time of impact.

Weiss and Hastings (13) classified these injuries: Type 1: Unicondylar fracture with transverse metaphyseal fracture: These injuries are usually displaced and malrotated and require open reduction and internal fixation (ORIF). If the fracture is nondisplaced, immobilization with close serial radiographic follow-up is recommended given the potential for interval displacement. Some hand surgeons recommend early percutaneous pin stabilization given the propensity of these fractures to displace. Type 2: Unicondylar fracture with an oblique metaphyseal fracture of varying length. This pattern is by far the most common accounting for one-half to two-thirds of these fractures. Due to the obliquity of the metaphyseal fracture, these fractures are highly unstable—even initially undisplaced fractures may settle during the healing period and lead to an angular deformity of the digit. Type 3: Bicondylar fracture with varying obliquity of the metaphyseal fracture. Type 4: Coronal plane condylar fracture (dorsal or volar). Coronal fractures are usually unstable osteochondral fragments. If the fragment is displaced, there is associated joint subluxation with proximal displacement of the middle phalanx. CT scan is helpful preoperatively in planning surgical approach and fixation. Type 5: Triplane fractures of the head of the proximal phalanx have been described by Chin and Jupiter (14). These are highly unstable articular injuries necessitating ORIF. Autogenous cancellous bone grafting may be needed to support the articular fragments. When the articular surface is not reconstructable, implant arthroplasty is considered. Preoperative Preparation Physical examination usually reveals rotational deformity during composite flexion or tenodesis. Scrutiny of radiographs of the injured digit is essential to assess joint alignment, displacement, and condylar malrotation in the sagittal plane. In select cases, CT scanning may be necessary to assess the fracture planes and fragment size more accurately. General versus regional anesthesia Mini-C arm Kirschner wires (0.045 in, 0.035 in, 0.028 in) Modular screws (1.5 mm, 1.3 mm, 1.1 mm) Technique Unicondylar fractures are approached from a midaxial approach on the side of the fracture by retracting the extensor tendon dorsally (Fig. 6-16). The ipsilateral transverse retinacular ligament of the extensor is released, and the conjoined lateral band together with the central extensor tendon is elevated dorsally to expose the fractured condyle. A dorsal capsulotomy affords visual confirmation of articular reduction. A fine dental pick or K-wire is passed into the condyle to assist with manipulation. Preservation of the collateral ligament origin minimizes the risk of osteonecrosis. Once the fracture is adequately reduced, the wire is advanced transversely across the fracture. Reduction can be stabilized with a tenaculum forceps. A lag screw is passed proximal to the K-wire. The K-wire is then removed and exchanged for a subchondral lag screw, which should avoid incarceration of the collateral ligament. A minimum of two wires/screws are used for rotational stability. Coronal condylar fractures remain challenging. Displaced fractures lead to joint instability and articular malunion when left untreated. Preoperative CT scan assists in selection of surgical approach (i.e., dorsal versus volar).

The fragment is gently manipulated back into position. K-wire or screw fixation is selected based on fragment size and comminution. Open reduction of bicondylar fractures requires visualization of the distal articular surface. At the PIP joint, a curved dorsal skin incision is used and the extensor mechanism is mobilized either by making an incision between the lateral and central slip on either side, or by elevating the extensor mechanism and creating a distally based V-shaped flap with the apex of the V situated at the proximal third of the proximal phalanx (i.e., reverse Chamay) (15). At the DIP joint, the fracture fragments are accessed P.72 P.73 on each side of the terminal extensor tendon. A transverse capsulotomy will allow visualization of the joint. The articular surface is reduced and provisionally stabilized with size appropriate K-wires. The articular fragments are then stabilized to the shaft with an oblique K-wire (Fig. 6-17). While this fixation will maintain reduction, it will not permit early motion and consideration must be given to stable internal fixation with a plate—either a dorsal Tplate or a laterally applied mini-condylar plate. Although insertion of a lateral condylar plate is technically more challenging, it causes least interference with the extensor mechanism. Laterally applied modular fixed angle plates have begun to replace mini-condylar blade plates. The extensor tendon interval is repaired with nonabsorbable sutures.

FIGURE 6-16 A: Preoperative radiographs demonstrate malrotated ulnar condylar fracture. CT was utilized in this case to better define the fracture plane. B: A dorsal curvilinear incision is utilized, followed by elevation of a full-thickness cutaneous flap. C: Division of the transverse retinacular ligament. D: Division of the transverse retinacular ligament allows retraction of the ipsilateral conjoined lateral band and central extensor followed by dorsal capsulotomy and fracture mobilization. E: Complete malrotation of the condylar fracture fragment on the ipsilateral collateral ligament is seen. F: Articular reduction and fixation with two modular hand screws.

FIGURE 6-16 (Continued) G: Tenodesis demonstrates restoration of the digital cascade. H: Final postoperative radiographs. I: Final clinical outcome at 6 months' follow-up.

FIGURE 6-17 K-wire fixation of bicondylar proximal phalangeal fracture. P.74

FIGURE 6-18 A: Complex complete articular fracture of the head of the proximal phalanx. B: Silicone implant arthroplasty performed as the articular surface was not amendable to reconstruction. In extensively comminuted phalangeal head fractures, external fixation is used when ligamentotaxis effects relative joint congruency. Arthroplasty may be considered in elderly low-demand individuals when the articular surface is not reconstructable or poor bone quality precludes stable fixation (Fig. 6-18). Pearls and Pitfalls Preservation of the collateral ligament origin minimizes the risk of osteonecrosis Screw length is critical to avoid collateral ligament (i.e., sagittal plane condylar fractures) and flexion tendon impingement (i.e., coronal plan condylar fractures) Selection of extensor tendon intervals is planned to afford optimal articular visualization. Postoperative Management Following stable fixation, active and active-assisted motion and reverse blocking exercises are initiated within the first postoperative week. A hand-based intrinsic plus splint is used in between range of motion sessions.

PHALANGEAL BASE FRACTURES Dorsal Base Fractures Isolated dorsal base fractures occur in the middle phalanx and distal phalanx and represent avulsion fractures of the central slip and terminal extensor tendons, respectively. At the PIP joint, these injuries may be a radiographic surrogate for a volar dislocation that has underwent spontaneous reduction. Treatment of the injury depends on radiographic alignment of the fragment following joint reduction and splinting in terminal extension. Operative treatment is indicated if the fragment remains displaced by 2 mm or more, if the joint is incongruent due to angulation of a large fragment, or if there is joint subluxation. Dorsal articular fractures at the DIP joint (i.e., mallet fractures) are common. Large fragments may result in joint instability and subluxation and require reduction and fixation (transarticular, dorsal block pinning, or formal ORIF). When there is no subluxation, nonoperative treatment is usually preferred. Articular remodeling can be seen, but patients are counseled regarding post-traumatic arthrosis. Large fracture fragments with resultant volar articular subluxation are amendable to ORIF.

Small nondisplaced/minimally displaced dorsal base fractures not associated with a volar PIP dislocation or extensor lag may be treated with a short arc of motion protocol (16) with the understanding that close serial clinical follow-up is needed to ensure that an extensor lag does not develop. Pinning the PIP joint in full extension will usually restore satisfactory alignment when the avulsion fragment is small and allow for the central slip avulsion fragment to unite. Open reduction and screw fixation via a dorsal approach may be considered for displaced, large fragments with residual joint subluxation (Fig. 6-19). An alternative method of fixation consists of a cerclage wire applied through transverse metaphyseal drill holes in the base of the middle phalanx and passed deep to the central slip (Fig. 6-20). Supplemental transarticular Kwire for 3 to 4 weeks is necessary to protect the fixation. P.75

FIGURE 6-19 A: Large, displaced central slip avulsion fracture with resultant volar rotatory subluxation of the PIP B: ORIF via dorsal approach utilizing modular screw fixation. Postoperative rehabilitation consisted of an active short arc of motion protocol with progressive reduction of the PIP flexion block.

FIGURE 6-20 A: Severe digital crush injury with dysvascular digit and (B) open, large, displaced central slip avulsion fracture. C: Postoperative PA and lateral radiographs following ORIF with cerclage wire transarticular fixation. Revascularization was performed following bony fixation. D: Final clinical outcome. P.76

Volar Lateral Fractures Fractures of the lateral volar base of the proximal or middle phalanx result from collateral avulsion and may be associated with joint dislocation. Minimally displaced lateral corner fractures that do not compromise joint stability or result in an incongruous articular surface can be treated by splinting followed by early protected motion. Displaced lateral corner fractures that compromise joint stability are treated with internal fixation. A palmar approach to the joint involves a chevron incision centered over the joint flexion crease. The interval between the neurovascular bundle and the flexor tendon sheath is developed. The cruciate-synovial window between the A2 and A4 pulleys is reflected. The flexor tendons are reflected laterally exposing the volar plate. The volar plate is then incised and reflected distally. The fragment is elevated and reduced. Tension band fixation (Fig. 6-21) and screw fixation (Fig. 6-22) provide stable fixation.

FIGURE 6-21 A: Index finger MCP joint RCL bony insertional avulsion. B: ORIF using figure-of-eight tension band technique.

FIGURE 6-22 A: Small finger open dorsal PIP fracture-dislocation. B: Under digital anesthetic, the open wound was first irrigated followed by closed reduction. Postreduction radiographs demonstrate a large displaced and

malrotated volar-radial marginal fracture at the base of the middle phalanx. C: Open reduction is performed via palmar exposure through the open palmar wound. The A2 and A4 pulleys are preserved, and the flexor tendons are retracted ulnarward. The volar plate remains attached to the volar-radial marginal fracture fragments (forceps). The metaphyseal donor site at the volar radial margin of the middle phalangeal base is visualized (arrow). P.77

FIGURE 6-22 (Continued) D: The articular fragments are anatomically reduced and internal fixation performed with a 1.3-mm modular hand screw while preserving the volar plate attachment on the articular fragment (arrow). E: The volar plate is repaired to the ulnar critical corner (dental probe) following fixation of the volar radial margin. Postoperative rehabilitation included early active motion with gradual reduction of a dorsal block splint. F: Final postoperative radiographs demonstrate preservation of joint space and maintenance of a congruous reduction. Full composite flexion was achieved. A small residual PIP flexion contracture did not require further treatment.

FIGURE 6-23 PIP joint palmar lip fracture stability is determined by the size of the palmar articular fragment size.

Plateau Fractures Compression injuries can cause radial or ulnar plateau impaction at the base of the middle phalanx or proximal phalanx. The radiographic findings may be subtle. Clinical exam under local anesthesia will demonstrate angular deformity as the phalangeal condyle engages the area of articular impaction. These injuries require open reduction from a dorsal or lateral approach with elevation of the articular fragment and bone grafting of the

metaphyseal void. An additional buttress plate should be considered if the fracture is felt to be unstable or if there is diaphyseal extension (17).

Volar Central Fractures and Fracture-Dislocations Palmar lip fractures are classified based on the stability of the interphalangeal joint, which is predicated on the size of the articular marginal fracture (Fig. 6-23). In most cases, the PIP remains stable with small palmar lip avulsion fractures (less than 30% articular surface) and are treated with early protected motion protocols. Occasionally, the marginal fracture may be significantly displaced or malrotated, but the PIP joint remains stable. Displaced volar marginal fractures may limit interphalangeal joint flexion and may be excised when joint stability is not compromised. Extrusion of the fragment into the flexor sheath has been described (18). P.78 Cadaveric analyses have demonstrated that when the articular fragment measures greater than 40% of the articular surface, the interphalangeal joint becomes unstable as the insertional footprint of the collateral ligaments remains with the volar articular fragment(s) (19). For larger fractures with associated dorsal instability, closed reduction by traction, volar translation, and flexion of the PIP joint may be successful if performed acutely (i.e., within a few days after injury). It is important to document under fluoroscopic guidance the joint position at which dorsal subluxation recurs. If more than 30 degrees of flexion is necessary to maintain a congruous reduction, stabilization is recommended. Extension block splinting (20) is applicable to cases when a closed, congruous reduction can be achieved. The dorsal block splint prevents extension of the PIP joint to the point of re-dislocation, while permitting PIP joint flexion. Custom splinting is initiated at 10 degrees more than the angle of PIP stability. The amount of flexion is reduced on a weekly basis by about 25% and full extension is delayed for about 4 weeks followed by buddy taping for an additional 2 weeks. Acceptable outcomes have been achieved with short periods of immobilization with the finger in as much as 50 to 60 degrees of flexion. Close follow-up with frequent radiographic examination is warranted to ensure that congruous reduction is maintained. Extension block pinning (21) is used when the reduced PIP cannot be adequately stabilized in a dorsal block splint. The PIP joint is reduced by applying manual traction and placing the joint into maximal possible flexion. A smooth Kirschner wire is then introduced percutaneously to engage the distal articular surface of the proximal phalanx and advanced in an intra-medullary fashion to engage the volar cortex of the proximal phalanx. Pin placement should avoid incarceration of the central slip. Gentle active range of motion exercise is initiated, and the K-wire is removed at 3 to 4 weeks. Closed reduction and percutaneous fixation of unstable solitary volar central articular fractures has been described with parallel percutaneous K-wires (22). ORIF of unstable fracture dislocations of the PIP joint is reserved for fracture-dislocations with a large, noncomminuted volar articular fragment amendable to screw fixation or in cases with delayed presentation when closed reduction or traction techniques are unsuccessful. Reduction and stabilization of the volar lip fracture of the middle phalanx restores adequate stability to allow early active motion and rehabilitation (23,24,25). A palmar exposure using either Bruner or midaxial incisions is performed from the proximal digital crease to the DIP flexion crease. The flexor tendon sheath is opened between the A2 and A4 pulleys and the flexor tendons retracted. Often the sheath is ruptured in this region and can be excised without significant functional loss. The volar plate is mobilized by releasing its lateral attachments to the collateral ligaments and joint is gently “shotgunned” (Fig. 6-24). The articular fragment is reduced and provisionally held size-appropriate K-wires. The reduction is assessed fluoroscopically, and the K-wires can then be sequentially exchanged for modular hand screws (usually 2 to 3

P.79 screws ranging from 1.1 mm to 1.3 mm). Rarely, a buttress plate for comminuted fractures may be needed. In chronic cases with an irreducible joint, the attachments of the collateral ligaments to the base of the middle phalanx are partially released in a volar to dorsal direction and the digit is gently hyperextended until it is fully “shotgunned.” The volar fragment is then fully visualized. Small comminuted fragments are removed and the major volar fragment is elevated, reduced and held either with a circumferential wire loop or with lag screws passed from volar to dorsal (26).

FIGURE 6-24 ORIF of large palmar lip fracture is performed through a volar exposure. When the volar central base is comminuted and cannot be stabilized, volar plate interpositional arthroplasty (VPA) (Fig. 6-25) to resurface the volar articular surface of the middle phalanx is indicated when less than 40% of the joint is involved (27). Dionysian and Eaton have reported on mid-term outcomes following VPA (28). At a mean of 11.5 years postoperatively, patients treated with VPA within 4 weeks of injury attained a mean 85 degree active arc of PIP motion compared to 65 degrees in patients treated with VPA at greater than 4 weeks. Four of seventeen patients showed some degree of joint narrowing at the follow-up examination. Volar central articular fractures of the DIP are treated similarly with closed reduction and transarticular fixation (Fig. 6-26), ORIF (Fig. 6-27), or VPA based on reducibility, joint stability, and fracture size and comminution. The P.80 P.81 P.82 integrity of the flexor digitorum profundus (FDP) is examined as closed FDP avulsions are seen in conjunction with volar rim and comminuted distal phalangeal base fractures (i.e., Leddy-Packer injury variants).

FIGURE 6-25 A: A radially based volar flap is utilized. B: A cruciate-synovial window between A2 and A4 is utilized, and flexor tendons are retracted. The collateral ligaments are released proximally. The volar plate is reflected proximally. The PIP joint is then “shotgunned.” C: The base of the middle phalanx is then debrided to create a symmetric transverse groove. Drill holes with 0.045 inch K-wires are placed at the periphery of the defect. D: 2-0 Prolene suture is passed through distal edge and the suture limbs are then passed volar to dorsal using straight thin Keith needles. E: The PIP joint is transfixed in 20 to 30 degrees of flexion. The volar plate is then advanced and the Prolene sutures are tied dorsally over a pullout button. The critical corners of the threedimensional ligamentous box supporting the PIP joint is restored when the volar plate is sutured to the collateral ligament insertions.

FIGURE 6-26 A,B: DIP dorsal fracture-subluxation secondary to volar marginal fracture. Note the dorsal “Vsign.” C,D: Closed reduction and transarticular fixation. E,F: Articular remodeling noted at latest follow-up.

FIGURE 6-27 A: Complex FDP avulsion with concomitant DIP volar marginal fracture. Note the additional osseous fragment at the A4 level. B: Palmar exposure is performed. Traumatic rupture of the A5 pulley is noted. The displaced malrotated volar articular fragment is seen as is the incarcerated FDP avulsion fragment beneath the A4 pulley. C: The volar articular fragment left attached to the volar plate, reduced, and secured with a bicortical modular hand screw. The FDP stump is seen emerging from the A4 pulley. D: The FDP is then advanced to its footprint in the distal phalanx and secured with a pullout suture tied over the dorsal nail plate. Hemi-hamate osteochondral autograft (HHA) reconstruction of the volar base of the middle phalanx has augmented the armamentarium of treatment options for previously irreconstructable articular injuries (29,30,31). HHA is indicated for comminuted, unstable PIP palmar lip fractures and fracture-dislocations. Comminuted, lateral plateau fractures that cause angular deformity and are not large enough for ORIF are also appropriate for HHA. HHA is also a satisfactory salvage option for patients who have redislocated after external fixation, ORIF, or VPA (Fig. 6-28). At a mean 4.5 years following HHA, Calfee et al. (31) reported a mean 70-degree arc of PIP motion with a 19-degree flexion contracture, and the mean DASH score indicated little functional impairment. HHA is contraindicated when there is advanced articular changes already present on the head of the proximal phalanx. In these cases, arthrodesis or implant arthroplasty are considered.

FIGURE 6-28 A: Preoperative radiographs demonstrating comminuted impacted volar central and lateral plateau articular fractures of the middle phalanx with dorsal subluxation of the PIP joint (V-sign; arrow). B: Intraoperative exposure as previously described. C: Postoperative radiographs following HHA demonstrating restoration of articular congruency. P.83 Various external fixation constructs are used for unstable, acute, comminuted volar central fractures, pilon fractures, and subacute/chronic PIP fracture-subluxations. Continuous dynamic skeletal traction can be applied to the digit through several transosseous proximal and middle phalangeal K-wire configurations and with the addition of force-coupling wires (32,33). Dynamic fixation constructs allow some degree of active motion to allow the concave articular surface to remodel around the convex condyles of the proximal phalanx while the joint remains unloaded from compressive and shear forces. Static external fixators also may be used (Fig. 6-29). If adequate reduction of the articular surface of the middle phalanx is not achieved by traction alone, the articular surface can be manipulated percutaneously or by open reduction. The fragments are then stabilized with multiple small K-wires, and traction is then applied (34). The variable configurations are all based on the concept of joint reduction via ligamentotaxis around the articular base.

FIGURE 6-29 A: PIP joint pilon fracture with associated metadiaphyseal fracture. B: Ligamentotaxis through ulnar-based unilateral static external fixator restores articular congruency and metadiaphyseal alignment. C: Osseous union with residual central articular defect at the base of the middle phalanx. D: Satisfactory clinical and functional outcome is achieved. P.84

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20. McElfresh EC, Dobyns JH, O'Brien ET: Management of fracture-dislocation of the proximal interphalangeal joints by extension-block splinting. J Bone Joint Surg Am 54(8): 1705-1711, 1972. 21. Viegas SF: Extension block pinning for proximal interphalangeal joint fracture dislocations: preliminary report of a new technique. J Hand Surg 17A: 896-901, 1992. 22. Vitale MA, White NJ, Strauch RJ: A percutaneous technique to treat unstable dorsal fracture-dislocations of the proximal interphalangeal joint. J Hand Surg Am 36(9): 1453-1459, 2011. 23. Hamilton SC, Stern PJ, Fassler PR, et al.: Mini-screw fixation for the treatment of proximal interphalangeal joint dorsal fracture-dislocations. J Hand Surg Am 31(8): 1349-1354, 2006. 24. Grant I, Berger AC, Tham SK: Internal fixation of unstable fracture dislocations of the proximal interphalangeal joint. J Hand Surg Br 30(5): 492-498, 2005. 25. Lee JY, Teoh LC: Dorsal fracture dislocations of the proximal interphalangeal joint treated by open reduction and interfragmentary screw fixation: indications, approaches and results. J Hand Surg Br 31(2): 138-146, 2006. 26. Weiss APC: Cerclage fixation for fracture dislocation of the proximal interphalangeal joint. Clin Orthop Relat Res 327: 21-28, 1996. 27. Eaton RG, Malerich MM: Volar plate arthroplasty of the proximal interphalangeal joint: a review of ten years' experience. J Hand Surg Am 5(3): 260-268, 1980. 28. Dionysian E, Eaton RG: The long-term outcome of volar plate arthroplasty of the proximal interphalangeal joint. J Hand Surg Am 25(3): 429-437, 2000. 29. Williams RM, Kiefhaber TR, Sommerkamp TG, et al.: Treatment of unstable dorsal proximal interphalangeal fracture/dislocations using a hemi-hamate autograft. J Hand Surg Am 28(5): 856-865, 2003. 30. Williams RM, Hastings H II, Kiefhaber TR: PIP Fracture/dislocation treatment technique: use of a hemihamate resurfacing arthroplasty. Tech Hand Up Extrem Surg 6(4): 185-192, 2002. 31. Calfee RP, Kiefhaber TR, Sommerkamp TG, et al.:. Hemi-hamate arthroplasty provides functional reconstruction of acute and chronic proximal interphalangeal fracture-dislocations. J Hand Surg Am 34(7): 1232-1241, 2009. 32. Slade reference; Schenck RR: Dynamic traction and early passive movement for fractures of the proximal interphalangeal joint. J Hand Surg 11A: 850-858, 1986. 33. Suzuki Y, Matsunaga T, Sato S, et al.: The pins and rubbers traction system for treatment of comminuted intraarticular fractures and fracture-dislocations in the hand. J Hand Surg 19B: 98-107, 1994.

34. Sarris I, Goitz RJ, Sotereanos DG: Dynamic traction and minimal internal fixation for thumb and digital pilon fractures. J Hand Surg 29A: 39-43, 2004.

Chapter 7 Operative Strategies for Basilar Thumb Fractures: Rolando's and Bennett's Fractures Michael D. Wigton Joelle Tighe Mark E. Baratz

INDICATIONS/CONTRAINDICATIONS Injuries to the base of the thumb metacarpal typically present with two patterns: Bennett's fracture or Rolando's fracture. Both fractures are characterized by inherent instability due to the ligamentous and tendinous insertions crossing the thumb carpometacarpal (CMC) joint. Additionally, these fractures involve the surface of the base of the thumb metacarpal (Fig. 7-1). Bennett's fracture was first described in 1885 by Dr. E.H. Bennett, in an address to the British Medical Association (1). This pattern involves a volar (palmar)-ulnar fracture fragment that remains attached to the tubercle of the trapezium by virtue of the anterior oblique ligament (AOL) (Fig. 7-2). The base of the metacarpal is subluxated in a proximal, radial, and supinated position due to the pull of the abductor pollicis longus. The radial subluxation of the metacarpal base leads to an adducted posture of the thumb metacarpal. Rolando's fracture involves an additional radial fragment with or without comminution of the base of the first metacarpal (2). Historically, nonoperative management was the treatment of choice in fractures of the base of the thumb metacarpal. In 1990, Livesley published a 26-year follow-up of nonoperatively treated Bennett's fractures in which 100% had decreased range of motion and grip strength (3). Since then, operative treatment has been favored. Surgical indications include displaced and/or unstable fractures or articular displacement greater than 2 mm. (Articular displacement alone is a debatable topic in the literature as there are conflicting reports of the long-term functional significance of joint degeneration.) The current standard of care in most cases is operative as few fractures of the base of the first metacarpal are neither stable nor nondisplaced. The CMC joint is a saddle articulation with concavity in the volar-dorsal plane and convexity in the radial-ulnar plane. This joint has an inherently wide range of motion in all planes allowing opposition, pinch, and grip functions of the thumb; this results in fracture instability. The AOL or beak ligament (Fig. 7-2) prevents volar subluxation of the metacarpal and accounts for the relative stability of the constant fragment in a Bennett's fracture. The abductor pollicis longus (APL) (Fig. 7-1) crosses the CMC joint and inserts on the proximal and radial aspect of the first metacarpal creating a deforming force in both a Bennett's and Rolando's fracture pattern. The APL accounts for the radial and dorsal translation of the metacarpal in Bennett's fracture and the displacement of the radial fracture fragment(s) in Rolando's fracture. The extensor pollicis P.86 longus (EPL) contributes to the dorsal and proximal migration of the metacarpal. Adduction of the metacarpal is seen most significantly with Bennett's fracture and is caused by the adductor pollicis (AdP) insertion at the proximal, ulnar base of the proximal phalanx. Together, these forces create the classic deformities seen.

FIGURE 7-1 Anatomical dissection of left thumb showing the first CMC joint with the APL insertion with the direction of pull indicated.

FIGURE 7-2 The left CMC joint is demonstrated with the palmar/volar (right) and dorsal (left) ligaments outlined. Nonoperative treatment is an option for stable, nondisplaced fractures. Cast immobilization with weekly close radiographic follow-up over the first 4 weeks postinjury is recommended as these fractures may have tendency for displacement even if initially nondisplaced. P.87

PREOPERATIVE PLANNING The mechanism of injury typically involves an axial load to the thumb, often occurring during a sporting event, fall, or higher-energy trauma such as a motor vehicle collision. Physical examination will reveal pain, swelling, and ecchymosis about the base of the thumb metacarpal. Swelling can be significant, resulting in distortion of usually palpable landmarks.

Radiographic evaluation includes posteroanterior and lateral views of the thumb (Figs. 7-3 and 7-4). Views specific for the thumb CMC joint may also be useful such as Robert's view (4) and Bett's or Gedda's view (5,6). These views may be difficult to obtain in the acutely traumatized hand. Preoperative computed tomography scan is reserved for chronic injuries to assess deformity, union, and the presence of arthritic changes.

FIGURE 7-3 PA radiograph and clinical photograph of the normal CMC joint.

FIGURE 7-4 Lateral radiograph and clinical photograph of the normal CMC joint. P.88 If closed reduction and pinning is contemplated, we prefer to attempt this in the first week following the injury to facilitate exposure and reduction. Initially, the fracture is immobilized in a thumb spica splint and the limb is elevated. The primary operative goal is a stable CMC joint with the articular surface of the metacarpal that is aligned with the trapezium. The base of the radial cortex of the metacarpal typically forms a “V” with the radial cortex of the trapezium. A “broken V” is seen with fracture-subluxation of the metacarpal. Restoration of the “V” indicates correction of the subluxation (Figs. 7-5 and 7-6). A perfect articular surface is not always possible, nor does it seem to alter the short- or long-term outcome. A number of techniques have been described for both Rolando's and Bennett's fractures. P.89 Closed reduction and percutaneous pinning, open reduction and internal fixation, traction pinning, and external

fixation may be viable options in either fracture pattern.

FIGURE 7-5 Line drawing representing the radial “v” as seen in the anatomically normal CMC articulation (left). In Bennett's fracture, the “v” is broken with CMC subluxation (right).

FIGURE 7-6 Radiograph showing the typical appearance of a Bennett's fracture with the volar ulnar constant fragment; the metacarpal is subluxated radial, proximal, and supinated. The radiographic “v” representing the reduced radial articulation is broken demonstrating joint subluxation. We prefer closed reduction and pinning for both injury patterns. Open reduction and internal fixation is reserved for fracture-dislocations where we cannot get reasonable alignment of the metacarpal base with respect to the trapezium or in Bennett's fractures or where there are two large fracture fragments.

SURGICAL TECHNIQUE The patient is placed in a supine position. We prefer regional anesthesia with a proximal block (axillary). The arm is positioned at 90 degrees from the body on an operating hand table. Intraoperative fluoroscopy is used for assessment of fracture reduction and fixation.

Closed Reduction With Percutaneous Pinning Bennett's Fracture Closed reduction and percutaneous pinning are preferred in the majority of the Bennett's

fracture during the acute phase provided the articular reduction is less than 1 to 2 mm of articular step-off (7,8). Closed reduction has been described with several methods including the passive screw-home technique. This technique takes advantage of an intact dorsal-radial ligament (9). The thumb is opposed and maximally pronated. The hitchhiker's position should be avoided as extension of the metacarpophalangeal (MCP) joint may lead to malreduction. Several pin configurations have been described. A transarticular technique as described by Wagner (10) has resulted in acceptable long-term functional outcomes but may have a higher rate of adduction deformity (11). This technique places one retrograde wire from the metacarpal base crossing the CMC joint into the trapezium. A second wire is placed from the intact metacarpal base into the volar ulnar fragment. Transmetacarpal pinning is also described with acceptable radiographic and functional outcomes despite the development of arthritis radiographically (12,13). This technique is particularly useful in fracture patterns that are axially unstable after reduction. Our preferred technique begins with traction, abduction, and pronation of the metacarpal. This is done with the MCP flexed and with pressure over the dorsal and radial aspect of the metacarpal base. A 0.045″ wire is then introduced into the base of the thumb metacarpal at the junction of the glabrous and nonglabrous skin. It is advanced into the far cortex of the index metacarpal. Intraoperative fluoroscopy is used to confirm that the “V sign” is restored. A second pin is placed from the base of the thumb metacarpal into the trapezium. If the CMC joint is incongruent or the articular reduction is outside of acceptable parameters, a second attempt at reduction or an open reduction can be performed. Following successful closed reduction and pinning, the wires are cut outside of the skin. A well-padded thumb spica plaster splint is applied, and the hand is elevated until the swelling resolves. The patient is encouraged to begin immediate active motion of the fingers. At two weeks, the splint is converted to a thumb spica cast with the thumb interphalangeal (IP) joint free to allow for active motion of the thumb IP joint. The cast and pins are removed at 4 weeks. The patient is then provided with a removable hand-based thumb spica splint for driving and light lifting for an additional 3 to 4 weeks. There are no clear guidelines for the duration of immobilization. The injury involves both a fracture and injury to the ligaments supporting the thumb CMC joint, and immobilization is intended to encourage healing of both elements. Rolando's Fracture Rolando's fracture involves at least two distinct articular fragments. When possible, we prefer indirect reduction with suspension of the thumb metacarpal by two parallel wires placed in the index metacarpal. The reduction is performed, as above, with traction, abduction, and pronation of the metacarpal. The MCP joint is held in a flexed position. A 0.045″ wire is then introduced into the base of the thumb metacarpal at the junction of the glabrous and nonglabrous skin. It is advanced into the far cortex of the index metacarpal. Intraoperative fluoroscopy is used to confirm that the “V sign” is restored. A second pin is placed parallel to the first pin.

Open Reduction and Internal Fixation Bennett's Fracture Open treatment of Bennett's fracture is considered when closed reduction fails to (a) reduce articular displacement within acceptable parameters or (b) restore proper metacarpal-trapezial alignment. There is no evidence, that we are aware, supporting open versus closed treatment. To emphasize, the importance of articular reduction is debatable, and therefore, the decision to open a Bennett's fracture should not be based on the ability to perfectly reduce the P.90 articular displacement alone (13). Our approach is admittedly arbitrary. We consider open treatment when closed reduction results in an unacceptable reduction of the articular surface or incomplete reduction of the “V sign.” We will also consider ORIF when there is a large ulnar fragment that will allow for solid interfragmentary fixation and joint reduction (Fig. 7-7).

When open treatment is performed, a Wagner approach is used through an incision on the dorsalradial aspect along the glabrous border over the CMC joint between the APL/EPB and the thenar muscles. This is curved volarly to the distal wrist crease up to the flexor carpi radialis tendon. Care is taken to avoid injury to branches of the superficial branch of the radial nerve and palmar cutaneous branch of the median nerve. The thenar muscles are carefully reflected subperiosteally from the volar aspect of the trapezium and proximal metacarpal. A longitudinal capsulotomy is then made to expose the CMC joint. Every attempt should be made to preserve all soft-tissue attachments to fracture fragments (Fig. 7-8).

FIGURE 7-7 PA radiograph demonstrating a Bennett's fracture.

FIGURE 7-8 Intraoperative clinical photograph showing the Wagner approach for ORIF of a Bennett's fracture. The two large articular fragments are seen within the wound. P.91

FIGURE 7-9 Clinical intraoperative photograph showing ORIF of a Bennett's fracture in progress. K-wires have been placed provisionally after anatomic reduction of the metacarpal articular surface.

FIGURE 7-10 The previously placed provisional K-wires have been exchanged for interfragmentary screws as definitive fixation. The articular surface is reduced, and the reduction is maintained with two parallel wires, 0.035″ or 0.045″, depending on the size of the fracture fragments (Fig. 7-9). The wires are removed one at a time and replaced with a 1.0-mm screw if a 0.035″ wire was used or a 1.5-mm screw if a 0.045″ wire was used (Fig. 7-10). Rolando's Fracture The degree of articular comminution associated with Rolando's fracture may be difficult to assess. In most cases, we use closed reduction and “suspension” as the preferred form of treatment. Following traction, abduction, and pronation, two 0.045″ pins are passed from the base of the thumb metacarpal into the base of the index metacarpal. If the reduction is unacceptable, the joint is exposed through a Wagner approach. Fracture fragments can be reduced and pinned or stabilized with interfragmentary screws. An alternative approach is open reduction with T-plate fixation. P.92

Pearls and Pitfalls These injuries result from the combined failure of bone and the supporting ligaments.

Bennett's fracture and Rolando's fracture are sufficiently uncommon that we don't have strong evidence to support one therapeutic approach over the other. Conventional wisdom suggests that alignment of the metacarpal with respect to the trapezium is as, or more, important than anatomic restoration of the articular surface. Restoration of the radiographic “V sign” of the radial trapeziometacarpal joint should guide the accuracy of CMC reduction. Closed reduction with percutaneous pinning of the thumb to the index metacarpal is the preferred first line of treatment for Bennett's fracture. Percutaneous pin placement at the junction of the glabrous and nonglabrous skin avoids nerve injury. Open treatment is reserved for fractures where acceptable reduction and alignment are not restored with closed methods or in Rolando's fracture where there is a large ulnar fragment. 0.035″ and 0.045″ pins can be exchanged for 1.0 mm and 1.5 mm screws, respectively.

POSTOPERATIVE MANAGEMENT Bennett's Fracture The splint is removed for pin site inspection at 10 to 14 days and is replaced with a thumb spica cast. The time of immobilization is arbitrary as the goal is to achieve both union of the bone and stability via the surrounding soft tissues. Our approach is to remove the pins at 6 weeks and apply a handbased thumb spica splint. At 8 weeks, the splint is removed for gentle use. By 10 to 12 weeks, the splint is discontinued. This approach is conservative. Some authors have advocated early motion in cases where ORIF with screw fixation has been used. At this time, we are unable to state whether these two techniques result in equivalent outcomes.

Rolando's Fracture The postoperative management for Rolando's fracture, in our hands, is identical to that for the Bennett's fracture.

REHABILITATION Therapy is typically initiated between 10 and 12 weeks after surgical treatment. The most common issues are adduction contracture, thumb IP joint and CMC stiffness, and weakness of pinch and grip. A web space static progressive stretching splint can be fabricated for part-time use. The therapist can design a stretching and strengthening protocol.

RESULTS Bennett's Fracture A number of studies have demonstrated acceptable outcomes with each of the described treatments. The resounding theme relates to the rate of posttraumatic arthritis seen and the lack of correlation with anatomic articular reduction (7,11,12,14). Lutz et al. reported on 46 Bennett's fractures treated with either closed reduction and pinning or open reduction and internal fixation with lag screws. These patients were not randomized; rather, they were treated with an algorithm where closed reduction was abandoned for open reduction when articular displacement remained greater than 1 mm. They found a slightly higher rate of adduction deformity with closed treatment; however, there was no correlation with pain or functional outcome. Leclère et al. reported on 28 patients treated with open reduction and internal fixation in retrospective review with an average of 83 months' follow-up. Radiographs were evaluated at 4 months postoperatively

and final follow-up to determine residual articular gapping or step-off and the presence of arthritis. In this small series, no correlation was seen between articular deformity and arthritis. They suggested that the etiology of arthritis in a joint such as the trapeziometacarpal joint may be more degenerative than posttraumatic.

Rolando's Fracture Only a few studies exist evaluating the outcomes of treatment of Rolando's fracture. van Nierkerk and Ouwens reported their series of thumb metacarpal base fractures. Seven of the twenty three P.93 patients were classified as having Rolando's fracture (15). Functional outcomes were acceptable in all patients, but 4 of 5 patients to develop advanced arthritic changes were those with Rolando's fracture. All Rolando's fractures in this series were treated by closed means. Langhoff et al. reported on a series of 17 Rolando's fractures treated with closed or open reduction and pin fixation based on ability to achieve articular reduction (16). Articular reduction was graded postoperatively, and functional outcome was assessed at a mean final follow-up of 5.8 years. No correlation was found between quality of reduction and function, range of motion, arthritic changes, or pinch or grip strength. Two recent studies reported on outcomes of external fixation. Houshian and Jing reported on 16 patients treated with miniexternal fixator spanning the trapeziometacarpal joint (17). Nine of the 16 had a comminuted pattern. Their fixation was supplemented with percutaneous Kirschner wires to improve articular alignment. Pain, loss of motion, loss of grip strength, and complications were all reported as minimal. Their protocol included early motion of all uninjured joints with weekly clinical follow-up. Marsland et al. also utilized a monolateral external fixator but without any supplemental fixation (18). Again, functional results were reported as satisfactory with the exception of one case, which required early removal of the fixator due to pin site infection.

COMPLICATIONS OF BENNETT'S AND ROLANDO'S FRACTURES Most modern studies report satisfactory outcomes with minimal pain, greater than 90 to 95% return of joint motion, pinch and grip strength, and low rates of posttraumatic arthritis. Late treatment of Bennett's fracture can be challenging and is associated with a higher rate of residual stiffness, subluxation, and posttraumatic arthritis. The step-off can be managed with osteotomy and screw fixation. Mild residual subluxation can be managed with reduction and pinning. Missed fracture with complete dislocation of the metacarpal carries the chance of redislocation. It is our preference in this situation to perform ligament reconstruction (Figs. 7-11, 7-12, 7-13, 7-14, 7-15 and 7-16). Most reported complications are P.94 P.95 due to loss of fixation with rates as high as 30% and pin tract infections when percutaneous pinning or external fixation is used. The rates of posttraumatic arthritis are understandably reported to be higher in Rolando's fracture than Bennett's fracture. It is important to remember that radiographic arthritis is not indicative of pain or functional outcome.

FIGURE 7-11 Lateral view of the thumb in a 17-yearold with a missed Bennett's fracture. Note that the thumb metacarpal base is completely dislocated.

FIGURE 7-12 Immediate post-op ORIF with suture suspension of chronic Bennett's fracture.

FIGURE 7-13 Lateral view 8 weeks' post-ORIF chronic Bennett's injury. Note restoration of the “T sign.”

FIGURE 7-14 AP view of the thumb CMC joint at 8 weeks showing early posttraumatic arthritis.

FIGURE 7-15 Radial abduction of the thumb 8 weeks after ORIF of chronic Bennett's fracture.

FIGURE 7-16 Opposition 8 weeks post-op ORIF chronic Bennett's fracture.

REFERENCES 1. Bennett EH: On fracture of the metacarpal bone of the thumb. Br Med J 2: 12-13, 1886. 2. Rolando S: Fractures of the base of the first metacarpal and a variation that has not yet been described. Clin Orthop Relat Res 445: 15-18, 2006. 3. Livesley PJ: The conservative management of Bennett's fracture-dislocation: a 26-year follow-up. J Hand Surg 3B: 291-294, 1990. 4. Ladd AL: The Robert's view: a historical and clinical perspective. Clin Orthop Relat Res 472: 1097-1100, 2014. 5. Dela Rosa TL, Vance MC, Stern PJ: Radiographic optimization of the Eaton classification. J Hand Surg [Br] 29B: 173-177, 2004. 6. Gedda KO: Studies on Bennett's fracture: anatomy, roentgenology, and therapy. Acta Chir Scand Suppl 193(Suppl): 39, 1954. 7. Cannon SR, Dowd GSE, Williams DH, et al.: A long term study following Bennett's fracture. J Hand Surg [Br] 11B: 426-431, 1986. 8. Cullen JP, Parentis MA, Chinchilli VM, et al.: Simulated Bennett fracture treated with closed reduction and percutaneous pinning. J Bone Joint Surg 79A: 413-420, 1997.

9. Edmunds JO: Traumatic dislocations and Instability of the trapeziometacarpal joint of the thumb. Hand Clin 22: 365-392, 2006. 10. Wagner CJ: Methods of treatment of Bennett's fracture-dislocation. Am J Surg 80: 230-231, 1950. 11. Lutz M, Sailer R, Zimmerman M, et al.: Closed reduction transarticular Kirschner wire fixation versus open reduction internal fixation in the treatment of Bennett's fracture dislocation. J Hand Surg [Br] 28B: 142-147, 2003. 12. Timmenga EJF, Blokhuis TJ, Maas M, et al.: Long-term evaluation of Bennett's fracture: a comparison between open and closed reduction. J Hand Surg [Br] 19B: 373-377, 1994. 13. Greeven APA, Alta TDW, Scholtens REM, et al.: Closed reduction intermetacarpal Kirschner wire fixation in the treatment of unstable fractures of the base of the first metacarpal. Injury 43: 246-251, 2012. 14. Leclère FMP, Jenzer A, Hüsler R, et al.: 7 year follow-up after open reduction and internal fixation in Bennett Fracture. Arch Orthop Trauma Surg 132: 1045-1051, 2012. 15. Van Niekerk JLM, Ouwens R. Fractures of the base of the first metacarpal bone: results of surgical treatment. Injury 20: 359-362, 1989. 16. Langhoff O, Anderson K, Kjaer-Peterson K: Rolando's fracture. J Hand Surg [Br] 16B: 454-459, 1991. 17. Houshian S, Jing SS. Treatment of Rolando fracture by capsuloligamentotaxis using mini external fixator: a report of 16 cases. Hand Surg 18: 73-78, 2013. 18. Marsland D, Saghrajka AP, Goldie B. Static monolateral external fixation for the Rolando fracture: a simple solution for a complex fracture. Ann R Coll Surg Engl 94: 112-115, 2012.

Chapter 8 Surgical Repair: Reconstruction of Acute and Chronic Thumb Metacarpophalangeal Ulnar Collateral Ligament Deficiency Thao P. Nguyen Ngozi Mogekwu Akabudike

INTRODUCTION The ulnar collateral ligament (UCL) is the primary stabilizer of the thumb metacarpophalangeal (MP) joint under radial or valgus stress. Injuries to the UCL are common after falls, sporting injuries, or motor vehicle accidents causing forced abduction or rotation and hyperextension at the thumb MP joint. Campbell, in 1955, coined the term “gamekeeper's thumb” to describe chronic attritional injury to the UCL seen in Scottish gamekeepers who killed their game by grasping the head of the animals, often rabbits, between their thumb and index finger to break the animals' necks (1). Acute injury to the UCL is termed “skier's thumb” because of the high incidence seen after skiing accidents (2). This occurs when the pole maintains the thumb in an abducted position causing radial deviation. Incompetence of the thumb UCL frequently leads to painful, chronic instability and poor function.

ANATOMY The thumb MP joint is a diarthrodial joint capable of abduction, adduction, flexion, and extension. Unlike the other fingers in the hand, the thumb MP joint must remain stable in both flexion and extension to resist the radial and ulnar stresses incurred during pinch and grasp. The thumb MP joint has considerable variation in the flexionextension arc and degree of valgus laxity (3,4). Stability of the thumb is critical for overall hand function and is often achieved at the expense of P.98 motion. Thumb MP joint stability is provided by the bony anatomy as well as dynamic and static restraints. Compared with the finger metacarpals, the thumb metacarpal head is less spherical and its cartilage is more limited on the dorsal aspect leading to further stability (5). The static restraints are the proper and accessory collateral ligaments, the palmar plate, and the dorsal capsule. The proper collateral ligament extends from the midaxis of the metacarpal head to the palmar aspect of the proximal phalanx (Fig. 8-1). Along with the dorsal capsule, this ligament is taut in flexion. The proper collateral ligament serves as the primary restraint to valgus stress with the MP joint flexed and prevents palmar subluxation of the proximal phalanx. The accessory collateral ligament is palmar to and contiguous with the proper collateral ligament at the metacarpal head and inserts onto the volar plate (Fig. 8-2). In extension, both the accessory collateral ligament and the volar plate are taut becoming the principal restraints to valgus stress in this position. The dynamic stabilizers include the extrinsic (extensor and flexor pollicis longus, extensor pollicis brevis) and intrinsic (abductor and flexor pollicis brevis, adductor pollicis) tendons and muscles. The adductor mechanism plays an important role as a dynamic stabilizer. Via its aponeurosis, it P.99 inserts onto the extensor expansion superficial to the MP joint capsule and UCL (Figs. 8-3 and 8-4). The adductor also has a deep insertion to the palmar aspect of the proximal phalanx via the ulnar sesamoid bone. Several structures can be injured after an acute valgus stress to the thumb MP joint. There may be a rupture of the dorsal capsule, volar plate, adductor mechanism, and extensor pollicis brevis. The thumb will be stable to valgus stress testing when these structures alone are involved. In contrast, when the proper collateral ligament is torn, instability will be present when the thumb is stressed in flexion. When the accessory collateral ligament is also torn, the tear is complete and the MP joint will be unstable in extension and flexion.

FIGURE 8-1 Black arrow points to the proper collateral ligament.

FIGURE 8-2 White arrow points to the accessory collateral ligament. Thumb UCL ruptures can occur at the midsubstance, proximally or distally. Distal avulsion off the base of the proximal phalanx is most common and can lead to a Stener lesion. This lesion occurs when the UCL is avulsed distally from the base of the proximal phalanx and displaces proximal and superficial to the adductor aponeurosis (6). The adductor aponeurosis becomes interposed between the torn UCL and its insertion at the base of the proximal phalanx, preventing it from healing in the correct anatomic location. Many feel this is the essential pathoanatomy determining the need for operative intervention.

FIGURE 8-3 Adductor aponeurosis.

FIGURE 8-4 Forceps lifting adductor aponeurosis. P.100

PREOPERATIVE PLANNING Patients will present with persistent pain, swelling, and frequently ecchymosis of the thumb. They complain about weakness with pinching or gripping activities and may demonstrate frank instability. Physical examination reveals localized swelling and often radial deviation and palmar subluxation of the proximal phalanx. A lump along the ulnar aspect of the thumb at the level of the metacarpal head may be palpated, which is highly suggestive of a Stener lesion. However, lack of a palpable mass does not rule out a Stener lesion (7). After palpation of the joint and before stability testing, anteroposterior and lateral radiographs are obtained to determine whether an avulsion fracture is present, typically from the ulnar base of the proximal phalanx. Associated fractures of the thumb metacarpal may also occur. After careful assessment of the radiographs, evaluation of joint stability with valgus stress testing is the most critical part of the examination. The goal is to determine whether the injury is incomplete (grade 1 or 2) or complete (grade 3). Testing stability in full extension and 30 degrees of flexion places the accessory and proper ligaments under tension, respectively. Carefully align the MP joint before stress testing because the thumb may already have assumed an angular posture secondary to ligamentous injury, thus influencing the measurement/severity of instability. Grade 1 injury is a sprain without joint instability. Grade 2 injury is an incomplete tear with joint instability but with a firm endpoint on stress testing. A firm endpoint and less than 30 degrees of valgus laxity rules out a complete UCL tear. Grade 3 injury is a complete tear with an unstable joint and no endpoint on stress testing. In complete ruptures, a Stener lesion is more than 80% likely (7). Instability is defined as opening of the joint more than 30 to 35 degrees without a firm endpoint (or 15 degrees more than the contralateral thumb) at both full extension and 30 degrees of flexion.7 Assessing the stability in flexion tests the proper collateral ligament, and stressing the joint in extension tests the accessory collateral ligament and volar plate. Valgus stress testing should not be avoided for fear of displacing a nondisplaced ligament rupture or avulsion fracture. The location of the bony fragment does not indicate the ligament location, nor does it indicate joint stability. Furthermore, if the ligament was not displaced at the time of an uncontrolled injury, controlled stress testing should not cause the ligament to displace. Other imaging studies, such as arthrogram, ultrasonography, and magnetic resonance imaging, can provide further sensitivity and specificity in the diagnosis of UCL tears; however, these are rarely required for accurate diagnosis.

INDICATIONS/CONTRAINDICATIONS Grade 1 and 2 UCL injuries are managed conservatively in a splint or thumb spica cast with the interphalangeal (IP) joint free for immediate range of motion (ROM). Immobilization of the MP joint is maintained for 3 to 6 weeks (8). Active and passive ROM can be started either immediately or after immobilization if radial deviation is avoided. Strengthening, gripping, and pinching activities are initiated at 6 weeks. Grade 3 or complete injuries, especially if a Stener lesion or joint subluxation is present, should be considered for surgical repair. Acute injuries can be primarily repaired, whereas chronic injuries may require reconstruction. The timing of the injury does not always predict the need for reconstruction, and primary repair can often be performed even months after initial injury. Surgery is also indicated for patients for whom nonoperative treatment has failed. These patients have persistent pain, decreased pinch and grip strength, difficulties with activities of daily living (opening jars and turning keys), continued instability, and potentially early arthrosis. The primary contraindication to repair or reconstruction is MP joint osteoarthritis. Degenerative changes are most often seen on radiographs but may only become apparent intraoperatively when the joint is explored. If the articular surfaces are arthritic or have severe chondromalacia, arthrodesis is indicated.

TECHNIQUES Approach Make a lazy-S or curvilinear incision centered over the ulnar aspect of the thumb MP joint (Fig. 8-5). Divide the subcutaneous tissue with dissecting scissors to the level of the extensor expansion and fascia and elevate dorsal and volar skin flaps. Carefully identify, dissect, and retract the branches of the dorsal sensory branch of the radial nerve (Fig. 8-6). Identify the oblique transverse fibers of P.101 the adductor aponeurosis, which may be torn. At this point, inspect for evidence of a Stener lesion and carefully dissect and protect the torn end of the ligament. Incise the aponeurosis longitudinally, staying parallel and 3 mm palmar to the extensor pollicis longus tendon (Fig. 8-7). Inspect the dorsal capsule, which may also be torn. Incise the capsule and inspect the joint for cartilage injuries and/or loose bodies. Perform any debridement as needed.

FIGURE 8-5 Marked surgical incision.

FIGURE 8-6 Dorsal sensory branch of the radial nerve.

FIGURE 8-7 Adductor aponeurosis incised, forceps holding up the cut edges. P.102

UCL Repair If palmar subluxation was seen on preoperative radiographs, the joint should be reduced and pinned before ligament repair. Pass a smooth 0.045-inch Kirschner wire antegrade through the base of the proximal phalanx and out through the skin on the radial side of the thumb. Reduce the joint and flex to 15 degrees, and then pass the wire retrograde across the joint. Fluoroscopy can be used to confirm joint reduction. We only pin the articulation when managing concomitant joint subluxation; otherwise, we perform repair without the additional fixation. Next, assess the proper and accessory collateral ligaments for the location of the tear. Most of the time, the ligaments are torn distally from the base of the proximal phalanx. If there is midsubstance tear, a direct repair can be carried out with an absorbable 3-0 or 4-0 suture in a figure-of-8 configuration. A small fragment of bone encountered with the avulsed ligament can be excised. However, larger fragments should be preserved and ORIF performed with Kirschner wires, screws, or a tension band. Identify the anatomic insertion site of the ligament at the ulnar aspect of the proximal phalanx. Prepare the site by debriding and curetting the bone. Mobilize the UCL stump and debride the distal end. Several techniques have been described to repair the ligament. A suture anchor or transosseus nonabsorbable suture technique can be used (Fig. 8-8).

Suture anchor technique: Place the anchor in the prepared bony bed. Pass one end of the nonabsorbable braided suture, such as 3-0 Ethibond, three to four times through the dorsal ligament in a locked running fashion, then cross transversely, and pass the suture along the volar ligament. Using the other limb of the suture, which is left free to slide in the anchor, pull the ligament down to the bone. Reduce the joint, and securely tie the sutures. Alternatively, both limbs of the suture can be placed through the torn ligament as a

horizontal mattress and secured as above.

Transosseus suture technique: Drill two bone tunnels in an ulnar to radial direction at the base of the proximal phalanx at the prepared bone site. Place a locking suture to grasp the ligament in a similar fashion as described above with two free suture ends at the distal stump (Fig. 8-9). Pass each free end of the suture through the bone tunnels, reduce the joint, and directly tie the sutures on the radial side of the bone (Fig. 810). Alternatively, the sutures can be tied over a button.

FIGURE 8-8 UCL repair: nonabsorbable sutures placed in ligament.

FIGURE 8-9 UCL repair: sutures passed through transosseous holes at insertion site at the proximal phalanx base. P.103

FIGURE 8-10 UCL repair: sutures tensioned and tied on radial side of proximal phalanx. Complete the repair by suturing the distal volar portion of the repaired ligament to the volar plate if possible.

Apply gentle radial stress to the joint to test the stability of the repair. Test passive flexion and extension to ensure maintained smooth motion. Hinging or gapping of the joint with passive motion indicates a repair that is not anatomically oriented or tensioned appropriately, and the repair should be revised. Suture the dorsal capsule if there is a large tear. Small tears can be left alone to avoid scarring and decreased flexion. Repair the adductor aponeurosis with a running absorbable suture, and reconfirm continuity and free gliding of the sensory nerve branches. Reapproximate the skin with a running subcuticular suture. Place the thumb in a forearm-based spica cast or splint with the MP joint slightly flexed and the IP joint free.

UCL Reconstruction With chronic UCL injuries in which the ligament cannot be repaired, reconstruction with a free tendon graft may be performed. Numerous techniques have been described to reconstruct the UCL. Demonstrated below is the modified Glickel technique (8,9). A biomechanical comparative study of four reconstructive techniques demonstrated restoration of stability, but only the Glickel technique most closely approximated normal MP motion (10). The tendon graft can be secured with anchors, interference screws, or bone tunnels with sutures tied over a bony bridge. Several graft options are available, but the palmaris longus is the preferred graft. When it is not available, the plantaris, a toe extensor, a slip of the abductor pollicis longus, or a portion of the flexor carpi radialis can be used (8,9). Expose the UCL as described in the “Approach” section above. Excise the proximal and distal stumps of the UCL. Evaluate the MP joint for articular cartilage damage. If the joint is arthritic, reconstruction is contraindicated and arthrodesis should be performed. Drill two bone tunnels along the ulnar side of the base of the proximal phalanx 4 to 5 mm distal to the articular surface. The volar and dorsal bone tunnels should converge at a 45degree angle within the medullary canal. The bone tunnel openings should be wide enough so that they will not crack when the tendon graft is passed through the holes. The tunnels can be connected and enlarged with a towel clamp and/or curved curette. Pass a heavy suture or flexible wire through the bone tunnels, and clamp both ends with a hemostat. The suture/wire will be used later to pass the tendon graft. Drill another bone tunnel at the metacarpal neck exiting radially. This tunnel should be large enough to pass both ends of the tendon graft. Pass a second heavy suture or flexible wire transversely from the ulnar to radial side of the metacarpal hole, and clamp the ends with another hemostat. Harvest the free tendon graft. Several graft options are available, but the ipsilateral palmaris longus is preferred. If unavailable, the plantaris, a toe extensor, a slip of the abductor pollicis longus, or a portion of the flexor carpi radialis can be used (9). Harvest the palmaris longus tendon with a tendon stripper or with separate transverse incisions at the proximal wrist crease and midforearm at the musculotendinous junction. Suture both ends of the free tendon graft with a locked running stitch using nonabsorbable braided suture. Using a flexible wire or suture at the proximal phalanx, pull one end of the tendon graft into and through P.104 the bone tunnels (Fig. 8-11). Be careful not to fracture the bony bridge when pulling traction. Take both limbs of the tendon graft, and pass them through the metacarpal bone tunnel from the ulnar to radial side (Fig. 8-12). Pull tension on the graft and test the tension by radially stressing the MP joint in flexion and extension. Ensure that the joint is concentrically reduced under fluoroscopy. If the joint is not reduced with just manual tensioning of the graft, a Kirschner wire is used. Bend and cut the wire end superficial to the skin. The Kirschner wire is left in place for 4 to 6 weeks. Tie the ends of the graft in a knot at the set tension. Secure the knot to the periosteum with 3-0 braided suture (Ethibond). An alternative is to place a bone anchor adjacent to the metacarpal tunnel and use the loaded sutures to secure the knot. If using interference screws, the appropriately sized bone tunnels are created at the origin of the ligament on the metacarpal head and at the insertion on the proximal phalanx base. The graft is anchored with an interference screw on the metacarpal first (Fig. 8-13). The other end of the graft is aligned with

the proximal phalanx base, and the appropriate length is marked. The graft is tensioned and then anchored in the proximal phalanx with a second interference screw with the joint in a reduced position (Figs. 8-14 and 8-15). Apply gentle radial stress to the joint to test the stability of the repair. Repair the adductor aponeurosis with an absorbable suture. Reapproximate the skin with a subcuticular running suture. Apply a forearm-based thumb spica splint or cast, leaving the thumb IP joint free.

FIGURE 8-11 UCL reconstruction: graft passed through the base of the proximal phalanx.

FIGURE 8-12 UCL reconstruction: graft limbs passed through the origin at the metacarpal. P.105

FIGURE 8-13 UCL reconstruction: graft anchored in metacarpal with interference screw.

FIGURE 8-14 UCL reconstruction: graft anchored in proximal phalanx.

FIGURE 8-15 UCL reconstruction: graft anchored in proximal phalanx. P.106

PEARLS AND PITFALLS Care should be taken to avoid excessive traction on the dorsal radial sensory nerve branches. When making the bone tunnels in the proximal phalanx, drill them wide enough so that the bone bridge does not fracture when the tendon graft is passed through the holes. Make sure the joint is in a reduced anatomic position before tensioning and securing the repair or reconstruction. Avoid aggressive repair of the dorsal capsule to avoid scarring and stiffness.

POSTOPERATIVE MANAGEMENT The thumb is immobilized in a thumb spica cast for 4 to 6 weeks postoperatively. At that time, the cast and pin if used are removed and the patient is transitioned to a removable thermoplastic splint. We prefer a hand-based thumb spica splint with the IP joint free to encourage motion at the remaining joints. The splint is to be worn at all

times except when doing exercises or bathing for 4 weeks. Hand exercises, done under the guidance of a hand therapist and at home, involve active and gentle activeassisted ROM exercises. After 4 weeks, the splint can be discontinued except when doing strenuous activities. Patients continue ROM exercises and begin strengthening exercises with putty and light gripping activities (8). At 12 weeks postoperatively, pinch and grip strengthening can be initiated. At 4 months after surgery, the patient is permitted full unrestricted activity.

RESULTS Clinical outcomes for acute primary UCL repair (11): Significantly better motion with early mobilization. Full or near full strength (key pinch and grip) was restored in all patients. Pain relief was significantly improved in all patients. Clinical outcomes for UCL reconstruction (11): Greater than 70% of patients had full stability at the MP joint compared with the uninjured side. Greater than 85% of patients experienced pain relief. Patients regained greater than 82% of grip and pinch strength compared with the uninjured side. Patients retained greater than 74% of the ROM at the MP joint.

COMPLICATIONS Excessive traction on the dorsal radial sensory nerve branches may cause numbness, hyperesthesia, or dysesthesia on the dorsoulnar aspect of the thumb. This generally tends to resolve over several weeks. However, more significant injury to the sensory nerve branches can lead to continued pain and even chronic regional pain syndrome with long-term poor results. Stiffness is a known complication of repair or reconstruction, and patients need to be appropriately counseled preoperatively. If the reconstruction is tensioned too tight or aligned incorrectly, patients can develop significant joint stiffness. The MP joint can develop laxity over time. This can be the result of the graft being placed too loose or increased stress during aggressive rehabilitation. Careful handling of the soft tissues and appropriate alignment and tensioning of the ligament repair/reconstruction should lead to long-term gratifying results for the patient and surgeon.

REFERENCES 1. Campbell C: Gamekeeper's thumb. J Bone Joint Surg Br 37: 148-149, 1955. 2. Gerber C, Senn E, Matter P: Skier's thumb. Surgical treatment of recent injuries to the ulnar collateral ligament of the thumb's metacarpophalangeal joint. Am J Sports Med 9: 171-177, 1981. 3. Coonrad RW, Goldner JL: A study of the pathological findings and treatment in soft-tissue injury of the thumb metacarpophalangeal joint. With a clinical study of the normal range of motion in one thousand thumbs and a study of post mortem findings of ligamentous structures in relation to function. J Bone Joint Surg Am 50: 439-451, 1968.

4. Palmer AK, Louis DS: Assessing ulnar instability of the metacarpophalangeal joint of the thumb. J Hand Surg 3: 542-546, 1978. 5. Joseph J: Further studies of the metacarpo-phalangeal and interphalangeal joints of the thumb. J Anat 85: 221-229, 1951. 6. Stener B: Displacement of the ruptured ulnar collateral ligament of the metacarpo-phalangeal joint of the thumb: a clinical and anatomical study. J Bone Joint Surg Br 44: 869-879, 1962. 7. Heyman P, Gelberman RH, Duncan K, et al.: Injuries of the ulnar collateral ligament of the thumb metacarpophalangeal joint. Biomechanical and prospective clinical studies on the usefulness of valgus stress testing. Clin Orthop Related Res (292): 165-171, 1993. P.107 8. Glickel S: Thumb metacarpophalangeal joint ulnar collateral ligament reconstruction using a tendon graft. Tech Hand Up Extrem Surg 6: 133-139, 2002. 9. Glickel SZ, Malerich M, Pearce SM, et al.: Ligament replacement for chronic instability of the ulnar collateral ligament of the metacarpophalangeal joint of the thumb. J Hand Surg 18: 930-941, 1993. 10. Lee S, Kubiak E, Lawler E, et al.: Thumb metacarpophalangeal ulnar collateral ligament injuries: a biomechanical simulation study of four static reconstructions. J Hand Surg 30: 1056-1060, 2005. 11. Samora J, Harris J, Griesser M, et al.: Outcomes after injury to the thumb ulnar collateral ligament—a systematic review. Clin J Sport Med 23: 247-254, 2013.

Chapter 9 Operative Management of PIP Dislocations and FractureDislocations Nikhil R. Oak Brian Najarian Jeffrey N. Lawton

BACKGROUND Proximal interphalangeal (PIP) joint fracture-dislocations are intra-articular injuries that also include a concomitant soft-tissue injury to the surrounding ligamentous and capsular structures. These injuries most often occur from an axial load, but a bending torsional load or combined mechanism of injury can also occur. Injuries to the PIP joint are among the most common in the hand (1). Evaluation and treatment may be delayed as the injury can often be dismissed as a “jammed finger” (2). Swelling, stiffness, arthritis, and permanent pain can be the result of inadequate treatment of these injuries (3). The head of the proximal phalanx is bicondylar and has almost complete articular congruency with the middle phalanx allowing for joint stability with axial loading (4). The PIP joint is crucial in our ability to grasp objects, contributing 85% of the total active motion necessary due to its unique anatomy with 110 degrees arc of motion (5,6). Stability in the flexion-extension arc is provided by the thick volar plate, proper and accessory collateral ligaments, checkrein ligaments, and joint capsule, which form a three-sided box with the dorsal aspect relatively devoid of stabilizing structures (6) (Fig. 9-1). The extensor complex plays a role in limiting volarly directed stresses. The precise anatomy of the joint allows for equal loading throughout motion; therefore, any subluxation or abnormalities in the joint can cause increased wear and arthritis (7).

CLASSIFICATION The pattern of joint injury depends on the direction, degree, and rate of force application. Injuries to the middle phalanx can be classified based on the portion of the articular surface involved and the direction of deformity (Fig. 9-2). Palmar lip fractures with dorsal subluxation or dislocations of the middle phalanx are the most common type of injury. These injuries are caused by axial loading and hyperextension of the middle phalanx on the head of the proximal phalanx. Palmar lip fractures can be graded based on the percentage of articular surface involvement and joint subluxation (7,8,9). Stable fractures are those that remain reduced in extension with less than 30% of articular surface involvement. Tenuously stable fracture-dislocations are those that involve 30% to 50% of the articular surface with reduction of the P.110 joint maintained with less than 30 degrees of flexion. Unstable fractures are those with greater than 50% of the articular surface involved or 30% to 50% involved but needing more than 30 degrees of flexion to maintain adequate reduction of the PIP joint (Fig. 9-3). Dorsal lip fractures occur with palmar subluxation of the middle phalanx and can be caused by axial loading with hyperextension or an avulsion fracture by hyperflexion (10). Stable injuries are P.111 those in which the joint remains reduced in extension. Unstable injuries are those demonstrating palmar subluxation of the middle phalanx with the joint in extension. Often, a disruption of the normal digital cascade accompanies palmar subluxations or dislocations.

FIGURE 9-1 PIP joint anatomy. The thick volar plate, proper and accessory collateral ligaments, checkrein ligaments, and joint capsule form a three-sided box.

FIGURE 9-2 PIP fracture-dislocation general classifications. A: Volar. B: Dorsal. C: Pilon.

FIGURE 9-3 A: Fracture-dislocation. B: Volar bone loss that can lead to instability.

FIGURE 9-4 Classification of unicondylar proximal phalangeal fractures. Pilon fractures of the middle phalanx are those where the volar and dorsal margins are disrupted with comminution of the central articular surface (10,11). These fractures are caused by high-energy axial load with the joint in partial flexion and are almost always unstable. Commonly, dorsal and palmar fragments surround a depressed central fragment. The proximal phalanx can also be involved in PIP fractures-dislocations. These injuries occur during an axial load through the tip of the finger. Proximal phalanx articular fracture patterns include unicondylar, bicondylar, or comminuted fractures. Unicondylar fractures can be classified into four basic groups: oblique volar, long sagittal, dorsal coronal, and volar coronal (12) (Fig. 9-4).

INDICATIONS It is important to promptly recognize the complexity of the initial injury and to understand appropriate treatment options. Most PIP dislocations and fracture-dislocations can be treated with closed reduction, splinting, early motion, and close follow-up. Open treatment of PIP joint dislocations or fracture-dislocations is indicated when the joint cannot be concentrically reduced or if the reduction cannot be maintained by closed methods. Open reduction is also indicated in open displaced fractures and most unstable fractures that present after a remote trauma. Unstable or tenuous fractures include those that require more than 30 degrees of flexion to maintain reduction. Attempting closed management of a fracture-dislocation that would require extreme flexion to prevent redislocation will likely result in a significant flexion contracture. Other indications for open reduction include significant articular depression, displacement, or joint incongruity. An irreducible joint is consistent with entrapment of a soft-tissue structure such as the volar plate, collateral ligament, and/or tendons in the joint, which necessitate surgical extraction prior to reduction. There are no absolute contraindications to surgical treatment of these injuries other than a medically unstable patient or inability of the patient to cooperate with operative treatment and postoperative rehabilitation. The goals of treating PIP joint fracture-dislocations include obtaining concentric joint reduction, restoring a stable arc of motion, and allowing early motion to minimize adhesions and contractures (11). If full stable extension is achieved, recovery is much simpler as regaining/correcting PIP joint extension is far more difficult than regaining/correcting flexion. Anatomic restoration is desirable but not as important as the above outlined goals (10,13).

P.112

PREOPERATIVE PREPARATION Presentation and Evaluation After injury, the PIP joint quickly stiffens. Pain and instability will limit motion in the acute period following injury. Subacute or chronic injuries will present with stiffness, loss of function, persistent swelling, and pain due to the fibrosis of the capsular and ligamentous structures of the joint. An adequate history must be obtained, which includes a detailed description of the mechanism of injury and any previous treatments. The neurovascular exam is generally normal; however, capillary refill and sensation should be documented. Skin and soft tissues should be inspected particularly at the level of the PIP flexion crease for any open or healed wounds that would indicate an open fracture-dislocation. Deformity noted in extension or flexion can indicate a volar or dorsal dislocation. Location and extent of swelling or tenderness can indicate which soft-tissue structures are injured. Attention should be paid to both axial and rotational alignments, which may be altered secondary to articular depression of a condyle. This can be recognized clinically as angulation when full digital flexion and extension is attempted. Passive and active range of motion should also be documented, including any deficits. A digital nerve block may be necessary for a thorough exam (5). Passive testing of joint stability can allow for the assessment of volar plate and collateral ligament integrity; subluxation during active range of motion suggests ligament disruption or a significant intra-articular fracture (1). It is important to note the range of motion through which the joint remains reduced. For dorsal dislocations, the degree of extension that results in instability or dislocation determines the angle for extension block splinting or pinning. Elson's test (14) can be performed to evaluate the integrity of the central slip of the extensor apparatus. From a 90-degree flexed position of the PIP joint, the patient can be asked to actively extend the PIP against resistance. If the central slip is still intact, the force will be demonstrated through the middle phalanx and the distal interphalangeal (DIP) joint will remain supple during this effort. If the DIP joint remains rigidly extended due to the compensatory extensor actions of the lateral bands alone, a complete rupture of the central slip can be documented. In an acute setting, the patient may need a local digital block to allow for a good effort.

Diagnostic Studies After clinical examination, radiographic views including posteroanterior (PA), lateral, and oblique views of the digit are required. Oblique views are helpful in identifying fracture planes and to judge the extent of fracture comminution. Radiographs can be misleading as a seemingly small fragment of bone may result in incompetence of structures that lead to joint instability. A postreduction true lateral is needed to determine the amount of articular involvement, and views in full PIP joint extension are used to evaluate the stability of the joint. With superimposition of the proximal phalangeal condyles, subtle subluxation of the middle phalanx can be detected. Dorsal subluxation of the joint produces the “V” sign caused by separation of the incongruous articular surface of the proximal phalanx head and undamaged portion of the middle phalanx base. Presence of the “V” sign indicates subtle joint instability (11) (Fig. 9-5). Dynamic fluoroscopy, when available, can also be very helpful in evaluating joint reduction and stability.

FIGURE 9-5 A: Lateral radiograph of an unstable PIP fracture-dislocation. Greater than 50% articular surface involvement with dorsal dislocation. B: The “V sign” dorsally that demonstrates an incompletely reduced PIP fracture. P.113 Palmar Lip Fractures Stable fractures maintain joint congruency in full PIP extension, tenuous fractures stay reduced with less than 30 degrees of flexion, and unstable fractures need more than 30 degrees of flexion to maintain joint congruency (4,5,10,11). Dorsal Lip Fractures Stability is assessed in full extension. Articular surface involvement is usually less than 50% when stable, but if there is any palmar subluxation in full extension or concern for central slip rupture, these fractures are deemed unstable (5,10). Pilon Fractures All pilon fractures are grossly unstable and involve up to 100% of the articular surface. They often have areas of central depression and peripheral comminution and have the greatest amount of joint disruption (4). Condylar Fractures Fractures of the head of the proximal phalanx also undergo the same workup as middle phalangeal base fractures. PA radiographs are beneficial to visualize articular step-off. Type I fractures have an oblique volar fracture pattern, which renders it highly unstable. These fractures can create both lateral angulation and rotational misalignment. Type II fractures have a long oblique fracture line in the sagittal plane, which also renders it unstable. Type III fractures have a dorsal coronal fragment, which is usually small and can be associated with a dorsal PIP joint dislocation. Type III fractures are often stable and can be treated with fragment excision unless the fracture involves greater than 50% of the condylar diameter in the PA plane. Type IV fractures have a palmar coronal fragment and can be associated with a volar PIP joint dislocation. These fragments are unstable and can interfere with flexion.

TECHNIQUES Closed Reduction Most PIP joint dislocations and fractures can be treated with closed reduction. This is almost always successful for acute dorsal PIP dislocations. Volar dislocations can be more problematic especially if there is a rotatory component to the deformity. Reductions can be performed immediately after injury or if in a delayed presentation with the help of a 1% lidocaine digital block. Complete a neurologic exam of the digit prior to block and confirm adequate anesthesia before the reduction maneuver.

Dorsal dislocations—apply gentle traction on the finger with the wrist in neutral position followed by a volar directed force on the base of the middle phalanx while holding the proximal phalanx steady.

Volar dislocations Without rotatory component—place wrist in neutral position and apply gentle longitudinal traction with a dorsally directed force to the middle phalanx and a volarly directed force on the proximal phalanx. With rotatory component—often more difficult to reduce as the head of the proximal phalanx becomes entrapped between the central slip and one of the lateral bands of the extensor mechanism. Attempt reduction by placing the metacarpophalangeal (MCP) and PIP joints in 90 degrees of flexion with wrist extension and apply light traction to the digit while rotating the middle phalanx in the direction opposite to the deformity.

Open Reduction: Positioning/Equipment Patient is placed supine with a radiolucent hand table. Brachial or forearm tourniquet can be placed prior to draping—can be inflated to 250 mm Hg after exsanguinating the arm prior to incision. Surgery can be performed under general or regional anesthesia. Axillary blocks can achieve adequate sensory anesthesia and motor relaxation of muscle groups. Supinate the operative hand. Optionally, it can be held in place with a “lead hand” malleable positioner. Mini C-arm fluoroscopy is utilized to assess and confirm fracture/joint reduction. Depending on the technique used—minifragment plate/screw set, 24-gauge cerclage wire, and/or Kirschner (K)-wires should be available.

Closed Reduction and Percutaneous Pinning When acute fractures are reducible by closed means and an anatomic reduction can be achieved, this can be maintained by percutaneous K-wire fixation. Fractures involving the articular surface can be compressed together by using a fracture reduction forceps externally. Mini C-arm is used to assess fracture reduction with a goal being an anatomic joint surface and congruent PIP joint. P.114 Reduction is then secured using percutaneous K-wires—a minimum of 2 is required to prevent redisplacement. Either 0.045- or 0.035-inch K-wires can be used based on the size of the fracture and the phalanx. Optimal fixation points in the proximal phalanx are distal and palmar as the central and dorsal regions have thin cortical elements and provide weaker fixation. For condylar fractures (9): K-wires are inserted from the contralateral dorsal side of the intact condyle and advanced palmarly into the fractured condyle. Holding the PIP joint in extension relaxes the conjoined lateral bands. K-wires may also be inserted from the palmar/lateral fractured fragment and advanced to the intact condyle. For palmar lip fractures (8,15): A towel clip can be used to reduce the volar fragment with one point placed percutaneously into the

middorsal base of the middle phalanx and other point percutaneously through the midline of the flexor tendons directly onto the volar fragment. The K-wire is manually inserted through the skin just lateral to the volar limb of the towel clip distal to the articular surface. The K-wire can then be drilled across the dorsal cortex of the middle phalanx and through the dorsal skin. This is then repeated on the other side of the volar lip so that two wires are now entering the volar fragment and exiting dorsally through the skin. The K-wires can be withdrawn from the dorsal side until almost flush with the volar fracture fragment. PIP joint alignment can be then be maintained with transarticular or extension block pinning. Obtain definitive PA, lateral, oblique images and place in dressing/digital splint.

Surgical Approaches Surgical approaches are chosen based on fracture pattern and the direction of instability. It is important to be familiar with several different surgical approaches including the volar (Bruner), dorsal (Chamay or Swanson), and midaxial approaches to the PIP joint. If the main fracture line or comminution pattern is dorsal, a dorsal or midaxial approach can be used. When the fracture is primarily volar, such as with palmar lip fracture-dislocations or pilon-type fractures, then a volar approach is chosen. Volar Approach (Bruner) (16,17) (Fig. 9-6) Incision is made on the palmar surface in a zigzag fashion from the MCP joint crease across the PIP joint to the DIP joint flexion crease. In a larger digit, two limbs of the Bruner incision may be necessary per segment. A thick subcutaneous ulnar-based flap is mobilized at the level of the flexor sheath. Digital neurovascular structures are mobilized next to the flexor sheath—this helps in avoiding traction on these structures as the joint is displaced during the exposure and surgical fixation. P.115 Underlying flexor tendons are exposed by either of the following: Incising flexor sheath over the PIP joint on three sides to create a rectangular flap between the A2 and A4 pulleys. Alternatively, the flexor sheath can be split longitudinally to expose the tendons. Both the flexor digitorum profundus and superficialis tendons can be retracted to the side to expose the volar plate—Penrose drain or silicone vascular vessel loops can be employed to retract the tendons. The PIP joint is exposed by dividing the volar plate transversely and just proximal to the distal insertion; this allows retraction of this proximally as a proximally based flap. The collateral ligaments are sharply incised or elevated to access more dorsal fracture fragments and to aid in joint reduction. For a more comprehensive exposure, a “shotgun” approach (18,19) can be used. The PIP joint is hyperextended after releasing the collateral ligaments from their origin and maintains alignment on its own accord at approximately 130 degrees of hyperextension. Assess the neurovascular bundles during this maneuver to ensure they subluxate dorsally and do not

sustain a traction injury. Dorsal Approach (Chamay) (20) (Fig. 9-7) A dorsal longitudinal skin incision is made proximally along the midline and curving distally around the dorsal aspect of the PIP joint to expose the extensor mechanism. A distally based flap of the central slip can be made in a V shape with the pedicle extending as far as the proximal third of the proximal phalanx. This flap can be reflected distally, and the intact lateral bands can subluxate volarly and laterally to provide adequate exposure of the PIP joint. After surgical fixation, the flap can be repaired with 4-0 nonabsorbable sutures and allows early active motion within the first few days. Alternatively, the central slip can be incised longitudinally (Swanson). Midaxial Approach (Fig. 9-8) After marking the interphalangeal joint axes of rotation, identify the midaxial line between these points. The skin incision on this midaxial line will be 2 mm dorsal to the digital nerve and artery. Avoid an ulnar-sided incision on the small finger and radial-sided incision on the index finger as these surfaces are important for surface contact. P.116 Identify Cleland's ligament with fibers running volar to dorsal and thin fascial layers around the digital nerve and artery. Divide Cleland's ligament and deep to the neurovascular bundle. The bundle should remain in the volar flap. Expose the lateral portion of the middle phalanx and lateral margin of the flexor sheath. PIP joint can be entered between the volar plate and accessory collateral ligament to inspect the joint for further surgical fixation. Conversely, for proximal phalanx fractures, the midaxial approach can be slightly modified (Fig. 9-9). After a standard midaxial incision, the transverse retinacular ligament can be incised. The conjoined lateral bands and extensor tendon can be retracted dorsally. This allows a dorsal capsulotomy to expose the articular surface of the PIP joint. P.117 Closure and Splinting Volar plate and central slip flaps can be closed with 4-0 nonabsorbable suture. Flexor tendon sheath is closed with 5-0 or 6-0 suture—can be either absorbable or nonabsorbable. After tourniquet is deflated, bipolar cautery is used to achieve hemostasis. Skin is closed with interrupted 5-0 nylon or nonabsorbable suture. The patient is then placed into an intrinsic plus volar-based splint with MCP joints flexed 70 to 90 degrees and IP joints extended based on postfracture reduction stability.

FIGURE 9-6 A: Bruner approach—palmar zigzag skin incision. B: Two limbs may be needed between flexion creases of large digits. C: After flexor sheath is exposed—it can be incised on three sides between the A2 and A4 pulleys and retracted laterally. D: Flexor digitorum superficialis and profundus tendons are exposed. E: PIP joint is distracted while flexor tendons are retracted laterally. F: Joint is gently hyperextended until it maintains this “shotgun” alignment.

FIGURE 9-7 Dorsal approach (Chamay). A: Incision midline with curves laterally along PIP and DIP joints. B: A distally based V-shaped flap of central slip is created and pulled distally to expose the PIP joint.

FIGURE 9-8 A: Midaxial (blue line) and midlateral (red line) approaches. Midaxial line can be approximated by flexing finger and marking points at the IP joints where flexion creases end dorsally. B: Cross-sectional diagram of these approaches. Midaxial approach is dorsal to the neurovascular bundle and midlateral is approximately at the level of the bundle.

FIGURE 9-9 A: Dorsoradial approach. B: Release transverse retinacular ligament. Probe is below the transverse retinacular ligament. C: Dorsally retract conjoined lateral band and central tendon to expose capsule. D: Capsulotomy allows for intra-articular fracture exposure. E: Fracture can be anatomically positioned and held by bone reduction forceps.

Dynamic or Static External Fixation (See Chapter 10: “External Fixation of Hand Fractures and Dislocations” for Additional Details) The use of traction via either static or dynamic external fixation employs the concept of ligamentotaxis to maintain general joint reduction (21,22). Agee (23,24) employed a force couple device using K-wires to lever the middle phalanx base and the head of the proximal phalanx to maintain joint reduction through the motion arc. Schenck (25) described another method of traction by using a pin placed transversely through the middle phalanx and attached to an external ring in order to distract the joint and allow adequate range of motion (26). Travelling traction or dynamic external fixation as described by Hastings and Ernst (27) employed a bent K-wire through the axis of rotation and the middle phalanx to provide longitudinal traction while permitting passive/active ROM. With traction techniques, it is important to have an intact dorsal cortex to prevent the PIP joint from subluxating.

Numerous studies have demonstrated good outcomes by accepting incomplete articular reduction and instituting early motion as long as the PIP joint remains congruous (13,24,26).

Extension Block Pinning (4,28,29) When reduction of unstable PIP joint fracture-dislocations is difficult to maintain using extension block splinting alone, extension block pinning with K-wires can be employed. Compared to standard immobilization or transarticular K-wire placement, there is a lower risk of permanent joint contracture because early active motion is encouraged. The PIP joint is flexed to 90 degrees. K-wire insertion point is confirmed with fluoroscopy. The K-wire is inserted in retrograde fashion down the shaft of the proximal phalanx approximately 30 degrees off the long axis under fluoroscopic guidance (Fig. 9-10). Joint reduction is confirmed and range of motion visualized under fluoroscopy. A 60-degree arc of motion is ideal. The blocking pin allows active motion but blocks extension beyond the point that joint subluxation occurs. Gently stress the PIP joint in extension under fluoroscopy to troubleshoot for potential instability. Postoperative care: Early active motion is encouraged. Active/passive PIP flexion can be undertaken immediately. Active PIP extension is allowed to the degree afforded by the blocking pin. K-wire is removed at 4 to 6 weeks.

FIGURE 9-10 K-wire is inserted 30 degrees off the long axis under fluoroscopic guidance. P.118

Minifragment Fixation (17,30-32) (Fig. 9-11) Lag screw fixation provides more rigid stability and allows for earlier range of motion. This type of fixation is indicated in larger fracture fragments with less comminution. Intraoperatively, it is not uncommon to discover that these fracture fragments are more comminuted than radiographs demonstrate and using screw fixation may further fragment the bone.

The joint and fracture is exposed using an appropriate exposure technique described previously. Soft tissues are cleared from the fracture site with a dental pick or Freer elevator. It is important to maintain cancellous and subchondral bone on the articular fragments; bone grafting may be required to prevent articular collapse. Dorsal radius autograft or allograft can be used into the metaphysis directly or through a cortical window. After anatomic reduction of the fracture, fragments can be preliminarily stabilized with bone reduction forceps or K-wires. Choose appropriate-sized screws based on fragment size—usually 1.0 to 1.7 mm. Drill the screw hole perpendicular to the fracture line and measure depth using the depth gauge. If fragment size permits, overdrill the near cortex equal to the screw's outer diameter in order to perform interfragmentary lag fixation. Use a self-tapping, minifragment cortical screw for fixation. Headless screws or countersinking the screw can be helpful in avoiding tendon and soft-tissue irritation. While screws are self-tapping, the use of a tap prevents stripping of screws and a more gentle handling of the fragments. P.119 In larger fragments, two screws or a screw with supplemental threaded K-wire can be used for rotational stability. For condylar fractures of the proximal phalanx, a similar technique is used (Fig. 9-12). The screw can be placed safely near the proximal origin of the collateral ligament. For more distal screws, the collateral ligament can be partially elevated subperiosteally from proximal to distal or a smaller screw can be placed just distal to the origin with the PIP joint in flexion. Following definitive fixation, put the digit through full ROM under mini C-arm fluoroscopy to ensure stable concentric reduction. If the joint does not remain concentrically reduced, fixation can be augmented with extension block pinning, transarticular K-wire (8,33), or dynamic external fixation (27). Postoperative care: Thermoplastic splint provides protected motion. Progressive active and active-assisted ROM begins post-op days 2 to 5 based on comfort. Close follow-up for 3 weeks to monitor for loss of reduction. Motion restrictions are removed at 5 to 6 weeks; continue therapy for 1 to 2 months after splint removal for continued ROM.

FIGURE 9-11 A-C: Preoperative AP, lateral, oblique radiographs of small finger PIP joint demonstrating large dorsal/ulnar fragment. D: Dorsal approach to PIP joint with fracture exposed. E: 1.7-mm screw placed to achieve stable fixation of the fragment. Screw head has been countersunk. F,G: AP and lateral postoperative radiographs.

FIGURE 9-12 A: Drilling across fracture. B: Measuring depth to judge screw size needed. C: Overdrilling fracture fragment for lag fixation. D: AP diagram of screw position for fracture fixation. E: Lateral diagram of screw position. F: Intraoperative view after screw fixation. P.120

Cerclage Wiring (19) (Fig. 9-13) This technique allows for reduction and fixation of multiple smaller articular fragments while also providing for early range-of-motion exercises. This technique requires the more thorough “shotgun” exposure so there is an increased risk of fibrosis and stiffness postoperatively. Volar incision is employed with a “shotgun” exposure of the PIP joint. Mobilize the neurovascular bundles and release the distal volar plate with a rim of tissue to allow repair. Carefully elevate most proximal portion of the central slip leaving the distal portion intact and clear a thin ring of periosteum around the bony fragments of the middle phalanx.

Wire loop can thus be tightened directly against the bone allowing for firm fixation of the fracture fragments. The funnel-shaped base of the middle phalanx aides in fixation and prevents postoperative slippage with early ROM. P.121 Use a 24-gauge steel wire to make a loop twisted on itself and fashion it so that it is slightly larger than the base of the middle phalanx. Reduce the fracture and seat the wire loop around the base. Gently tighten the wire loop using a tonsil to allow for circumferential compression of the fracture fragments. Be aware of central depression and joint subluxation after confirming articular reduction. Cut the twisted free end of the loop and seat the end on the volar or volar lateral surface of the middle phalanx base flush to the cortex. This wire will be covered by the repaired volar plate to prevent mechanical irritation of the flexor tendons. If necessary, supplementary K-wire fixation may be used to allow for further fixation prior to final tightening of the cerclage wire. Postoperative care is very similar to the above listed care after minifragment fixation. Focus on aggressive early active range of motion.

FIGURE 9-13 Cerclage wire fixation. A: Preoperative lateral radiograph showing pilon-type pattern. B: Volar “shotgun” exposure shows volar fragment with central articular depression. C: View after reduction and cerclage wire fixation allowing circumferential compression. D: Postoperative radiograph conforming reduction of central articular fragment.

Volar Plate Arthroplasty (4,18,34-36) (Fig. 9-14) Volar plate arthroplasty has been described as an option when the articular surface in dorsal fracture-dislocation cannot be restored. Some authors use this technique to salvage chronic fracture-dislocations, while others prefer this for many acute injuries with bone loss and comminution. This method advances the volar plate into the middle phalangeal fracture defect to restore stability and resurface the joint articulation. Volar Bruner incision and “shotgun” approach is used to enter the joint. Volar plate is detached from the middle phalanx and from the radial/ulnar margins, keeping as much tissue as possible. Both collateral ligaments should be elevated or released to allow for joint hyperextension. In chronic cases, sharp release of checkrein ligaments may be necessary for advancement of the volar plate. It is important to leave the central portion intact for blood supply. Dorsal capsulotomy may be required for full range of passive motion in chronic cases. P.122 After hyperextension to provide a “shotgun” view, small fracture fragments are debrided. Create a transverse trough on the middle phalanx at the junction of the joint surface and fracture defect with a small rongeur or osteotome. Depth of trough should be equal to the thickness of the volar plate. Proximal ulnar and radial margins of volar plate flap are secured with 3-0 nonabsorbable suture placed in locking fashion. Two straight Keith needles are passed through each side of the trough created earlier with a wire driver aiming central and distally to penetrate through the cortex and central slip. Sutures are pulled through bone tunnels using the needles as the PIP joint is flexed. Mini C-arm fluoroscopy is used to ensure reduction of the PIP joint. If ROM is limited, you may need to advance the volar plate flap more distally by releasing checkrein ligaments or step cutting lengthening the ligaments. Sutures can be tied over a button dorsally or directly to the dorsal periosteum (below). Make a dorsal skin incision with a no. 11 blade with needles in place prior to pulling suture through—this prevents inadvertent cutting of the suture. After a small incision distal to the insertion of the central slip, at the triangular aponeurosis, the sutures are then tensioned down to the periosteum. A transarticular K-wire can be used to protect the reconstruction postoperatively but prohibits early motion. Some authors have advocated using dynamic distraction and external fixation to protect the reconstruction and allow early motion postoperatively (8,10,21). Alternatively, extension block pinning may aid in postoperative therapy. Post-op care:

Transarticular K-wire can be removed in 2 to 3 weeks. Continue extension block splitting up to 6 weeks. If a suture button is used, this can be removed at 6 weeks and then work on ROM.

FIGURE 9-14 A: Incision for volar plate arthroplasty. B: Approach for volar plate arthroplasty and VP mobilized— in forceps. Note N/V bundles mobilized and windows on both the radial and ulnar aspects of the flexor tendons. C: Insertion of volar plate by using a locking stitch passed into trough through holes drilled with Keith needles and then tied over dorsal middle phalangeal periosteum/central slip insertion.

Hemihamate Autografting (37-41) Hamate osteochondral autografting is a technique to re-establish the palmar base of the middle phalanx in dorsal fracture-dislocations when fracture comminution does not allow for restoration of the joint and traction is unable to maintain joint stability. Proposed by Hastings (39), the contour of the palmar articular surface of the middle phalanx can be reproduced by using the anatomically similar contour of the hamate articulation with the 4th and 5th metacarpal bases. Some authors propose that this is the treatment of choice for fractures involving 50% of the volar articular surface that is not amenable to primary internal fixation (37). Volar Bruner incision with “shotgun” exposure is used as described previously. Abnormal area or fracture fragments on palmar joint surface are identified and removed after measurements made with calipers. The height of the defect is determined by measuring the impacted fragments (Fig. 9-15A). A rongeur or saw can be used to create a smooth surface at the volar and distal margins of the base. Alternatively, bone wax can be used to model the defect and aid in contouring the hamate graft.

Hamate autograft harvest. A 3-cm transverse incision is made just proximal to the carpometacarpal joint at the bases of the ring and small fingers. Fluoroscopy is used to confirm accurate placement of the incision (Fig. 9-15B). Dorsal capsulotomy is made to visualize the hamate. Graft dimensions are marked using the distal articular ridge as a reference. Axial and sagittal cuts can be made with a small saw blade or osteotome with care taken to prevent damaging the articular surface. A proximal trough is created to allow the coronal plane cut to be placed appropriately. The graft should be slightly larger than measured to allow for contouring (Fig. 9-15C). The graft is then given final contours and placed into the defect at the base of the middle phalanx that was debrided earlier. Graft is provisionally stabilized with a K-wire followed by definitive fixation with two 1.0- or 1.5-mm screws in a volar to dorsal direction (Fig. 9-15D). The PIP joint is then reduced and assessed fluoroscopically to confirm correct screw length, graft positioning, and range of motion (Fig. 9-15E, F). The articular surface of the hamate is thicker than the middle phalanx, so a radiologic stepoff may be seen when no articular step-off between the graft and phalangeal base is actually present. P.123 P.124 The volar plate is reattached to the collateral ligaments along the lateral margins of the middle phalanx, and the reflected flexor sheath can be interposed. Post-op course: bulky dressing and dorsal splint applied with PIP held in 20 degrees of flexion. Begin limited ROM within a week from surgery with figure-of-eight splint and a 15-degree extension block for a period of 6 weeks prior to ramping up activities as tolerated.

FIGURE 9-15 A: Volar “shotgun” exposure of joint demonstrating depressed and malunited volar fragment. B: Incision for hamate autograft—fluoroscopy used to confirm site. C: Hamate autograft. D: Graft fixed with two 1.5mm screws in a volar to dorsal direction. E,F: AP and lateral radiographs demonstrating fixation and reduction.

PEARLS AND PITFALLS PIP joint dislocations and fracture-dislocations can often be missed and thought of as a “jammed finger.” Avoid forceful passive testing for stability, which can convert a partial ligamentous injury to a complete tear. Preserve the A2 and A4 pulleys to avoid bowstringing of the flexor tendons in the “shotgun” approach. If fracture fragments are too small or comminuted, screw fixation may further worsen bone loss and fixation may be inadequate. Screw or K-wire fixation in the middle phalanx base should be angled distally to maximize length and purchase. Minimize the number of passes when drilling with K-wires or with screws as this may result in further fracture

fragmentation. Always check fluoroscopic images postreduction and take PIP joint through arc of motion to ensure adequate stability. Lateral images are important to ensure implant does not violate the extensor mechanism or remain too prominent causing soft-tissue irritation. Bony defects should be filled with bone graft to prevent subsidence and recurrent subluxation.

COMPLICATIONS Posttraumatic arthritis PIP joint stiffness, flexion contracture, and extensor lag Persistent PIP joint subluxation or dislocation Loss of fracture fixation or worsening displacement Deep infection or pin site infection Numbness/paresthesias Vascular injury Malunion or nonunion Boutonniere deformity Chronic pain

RESULTS Fifteen patients treated with various ORIF techniques including K-wire, tension band, and screw fixation —the average post-op ROM was 17 to 90 degrees (9). Grant (31) reported on 14 patients after miniscrew or plate fixation who had an average total PIP ROM of 100 degrees, while Cheah (42) noted average PIP motion of 75 degrees in 13 patients. Stern (13) discussed results after pilon fractures of the PIP joint treated with splinting, traction or open reduction, and K-wire fixation. They found at 25-month follow-up that skeletal traction had fewer complications and comparable outcomes when compared to open reduction with average ROM of 80 degrees versus 70 degrees (open). Weiss (19) described 12 patients treated with cerclage fixation. At an average of 2.1-year follow-up, 11/12 patients demonstrated no degenerative changes, average total arc of motion was 89 degrees without implant failure, and all patients treated had pain-free motion. Malerich (18,34) discussed 17 cases of volar plate arthroplasty; only 3 patients reported mild pain, and an average of 95 degrees of PIP motion was restored. Radiographs showed marked remodeling of the disrupted surface. However, 6 to 12 degrees of flexion contracture resulted. They found a higher chance of redislocation if greater than 50% of the middle phalangeal base is involved. Calfee et al. (37) studied 33 patients treated with hemihamate arthroplasty. All patients healed and maintained joint reduction. Average PIP arc was 71 degrees for acute fractures and 69 degrees in chronic injury reconstructions. They concluded it was a good treatment choice for fractures involving greater than 50% of the articular surface that is not amenable to primary internal fixation.

P.125 Salter (43) reviewed the effect of motion on articular cartilage and found that cartilage undergoes deterioration if motion is limited and that the articular surface remodels over time. Numerous studies and clinical reports support the theory that anatomic surface restoration is unnecessary if subluxation is corrected and motion is instituted shortly after injury (22,23,30,43).

REFERENCES 1. Chinchalkar SJ, Gan BS: Management of proximal interphalangeal joint fractures and dislocations. J Hand Ther 16(2): 117-128, 2003. 2. Williams CS IV: Proximal interphalangeal joint fracture dislocations: stable and unstable. Hand Clin 28(3): 409-416, xi, 2012. 3. Kiefhaber TR, Stern PJ: Fracture dislocations of the proximal interphalangeal joint. J Hand Surg Am 23(3): 368-380, 1998. 4. Blazar PE, Steinberg DR: Fractures of the proximal interphalangeal joint. J Am Acad Orthop Surg 8(6): 383-390, 2000. 5. Freiberg A, Pollard BA, Macdonald MR, et al.: Management of proximal interphalangeal joint injuries. Hand Clin 22(3): 235-242, 2006. 6. Leibovic SJ, Bowers WH: Anatomy of the proximal interphalangeal joint. Hand Clin 10(2): 169-178, 1994. 7. Schenck RR: Classification of fractures and dislocations of the proximal interphalangeal joint. Hand Clin 10(2): 179-185, 1994. 8. Elfar J, Mann T: Fracture-dislocations of the proximal interphalangeal joint. J Am Acad Orthop Surg 21(2): 88-98, 2013. 9. Hastings H II, Carroll C IV: Treatment of closed articular fractures of the metacarpophalangeal and proximal interphalangeal joints. Hand Clin 4(3): 503-527, 1988. 10. Kang R, Stern PJ: Fracture dislocations of the proximal interphalangeal joint. J Am Soc Surg Hand 2(2): 47-59, 2002. 11. Calfee RP, Sommerkamp TG: Fracture-dislocation about the finger joints. J Hand Surg Am 34(6): 11401147, 2009. 12. Weiss AP, Hastings H II: Distal unicondylar fractures of the proximal phalanx. J Hand Surg Am 18(4): 594-599, 1993. 13. Stern PJ, Roman RJ, Kiefhaber TR, et al.: Pilon fractures of the proximal interphalangeal joint. J Hand

Surg Am 16(5): 844-850, 1991. 14. Elson RA: Rupture of the central slip of the extensor hood of the finger. A test for early diagnosis. J Bone Joint Surg Br 68(2): 229-231, 1986. 15. Vitale MA, White NJ, Strauch RJ: A percutaneous technique to treat unstable dorsal fracture-dislocations of the proximal interphalangeal joint. J Hand Surg Am 36(9): 1453-1459, 2011. 16. Bruner JM: Surgical exposure of the flexor pollicis longus tendon. HAND 7(3): 241-245, 1975. 17. Green A, Smith J, Redding M, et al.: Acute open reduction and rigid internal fixation of proximal interphalangeal joint fracture dislocation. J Hand Surg Am 17(3): 512-517, 1992. 18. Eaton RG, Malerich MM: Volar plate arthroplasty of the proximal interphalangeal joint: a review of ten years' experience. J Hand Surg Am 5(3): 260-268, 1980. 19. Weiss AP: Cerclage fixation for fracture dislocation of the proximal interphalangeal joint. Clin Orthop Relat Res (327): 21-28, June 1996. 20. Chamay A: A distally based dorsal and triangular tendinous flap for direct access to the proximal interphalangeal joint. Ann Chir Main 7(2): 179-183, 1988. 21. Krakauer JD, Stern PJ: Hinged device for fractures involving the proximal interphalangeal joint. Clin Orthop Relat Res (327): 29-37, June 1996. 22. Morgan JP, Gordon DA, Klug MS, et al.: Dynamic digital traction for unstable comminuted intra-articular fracturedislocations of the proximal interphalangeal joint. J Hand Surg Am 20(4): 565-573, 1995. 23. Agee JM: Unstable fracture dislocations of the proximal interphalangeal joint of the fingers: a preliminary report of a new treatment technique. J Hand Surg Am 3(4): 386-389, 1978. 24. Agee JM: Dynamic traction and early passive movement for fractures of the proximal interphalangeal joint. Clin Orthop Relat Res (214): 101-112, Jan 1987. 25. Schenck RR: Dynamic traction and early passive movement for fractures of the proximal interphalangeal joint. J Hand Surg Am 11(6): 850-858, 1986. 26. Finsen V: Suzuki's pins and rubber traction for fractures of the base of the middle phalanx. J Plast Surg Hand Surg 44: 209-213, 2010. 27. Hastings H II, Ernst JM: Dynamic external fixation for fractures of the proximal interphalangeal joint. Hand Clin 9(4): 659-674, 1993. 28. Viegas SF: Extension block pinning for proximal interphalangeal joint fracture dislocations: preliminary report of a new technique. J Hand Surg Am 17(5): 896-901, 1992.

29. Maalla R, Youssef M, Ben Jdidia G, et al.: Extension-block pinning for fracture-dislocation of the proximal interphalangeal joint. Orthop Traumatol Surg Res 98(5): 559-563, 2012. 30. Hamilton SC, Stern PJ, Fassler PR, et al.: Mini-screw fixation for the treatment of proximal interphalangeal joint dorsal fracture-dislocations. J Hand Surg Am 31(8): 1349-1354, 2006. 31. Grant I, Berger AC, Tham SK: Internal fixation of unstable fracture dislocations of the proximal interphalangeal joint. J Hand Surg Br 30(5): 492-498, 2005. 32. Freeland AE, Benoist LA: Open reduction and internal fixation method for fractures at the proximal interphalangeal joint. Hand Clin 10(2): 239-250, 1994. 33. Deitch MA, Kiefhaber TR, Comisar BR, et al.: Dorsal fracture dislocations of the proximal interphalangeal joint: surgical complications and long-term results. J Hand Surg Am 24(5): 914-923, 1999. 34. Malerich MM, Eaton RG: The volar plate reconstruction for fracture-dislocation of the proximal interphalangeal joint. Hand Clin 10(2): 251-260, 1994. 35. Dionysian E, Eaton RG: The long-term outcome of volar plate arthroplasty of the proximal interphalangeal joint. J Hand Surg Am 25(3): 429-437, 2000. 36. Blazar PE, Robbe R, Lawton JN: Treatment of dorsal fracture/dislocations of the proximal interphalangeal joint by volar plate arthroplasty. Tech Hand Up Extrem Surg 5(3): 148-152, 2001. 37. Calfee RP, Kiefhaber TR, Sommerkamp TG, et al.: Hemi-hamate arthroplasty provides functional reconstruction of acute and chronic proximal interphalangeal fracture-dislocations. J Hand Surg Am 34(7): 1232-1241, 2009. 38. Capo JT, Hastings H II, Choung E, et al.: Hemicondylar hamate replacement arthroplasty for proximal interphalangeal joint fracture dislocations: an assessment of graft suitability. J Hand Surg Am 33(5): 733-739, 2008. P.126 39. Hastings HCJ, Steinberg B, Stern P: Hemicondylar hamate replacement arthroplasty for proximal interphalangeal joint fracture/dislocations (abstr). Presented at the 54th Annual Meeting of the American Society for Surgery of the Hand, Boston, MA, 1999. 40. Williams RM, Hastings H II, Kiefhaber TR: PIP fracture/dislocation treatment technique: use of a hemihamate resurfacing arthroplasty. Tech Hand Up Extrem Surg 6(4): 185-192, 2002. 41. Williams RM, Kiefhaber TR, Sommerkamp TG, et al.: Treatment of unstable dorsal proximal interphalangeal fracture/dislocations using a hemi-hamate autograft. J Hand Surg Am 28(5): 856-865, 2003. 42. Cheah AE, Tan DM, Chong AK, et al.: Volar plating for unstable proximal interphalangeal joint dorsal

fracture-dislocations. J Hand Surg Am 37(1): 28-33, 2012. 43. Salter RB: The physiologic basis of continuous passive motion for articular cartilage healing and regeneration. Hand Clin 10(2): 211-219, 1994.

Chapter 10 External Fixation in the Hand William H. Seitz Jr

INTRODUCTION Miniaturization of external fixation apparatus, applications, and techniques has evolved to afford hand surgeons a unique and useful tool to treat a variety of difficult conditions that they face on a regular basis. Principles as applied to the hand are similar to those applied across segments of the entire limb and long bones; however, the complexities of the hand including tendon gliding, multiple small joint interactions, fine neurologic structures, and limited space for skeletal targeting all require technical expertise and careful planning and execution of the process. The techniques of applying miniature external fixation in the hand have application in acute trauma, in posttrauma reconstruction and staged management of infections, in burn reconstruction, in deformity correction, and in congenital hand surgery (1,2,3,4,5,6,7,8,9,10). This chapter will review the indications, contraindications, perioperative preparation, surgical technique, “pearls and pitfalls,” postoperative management, potential complications, and their management with an overview of expected results.

INDICATIONS Acute trauma Unstable intra-articular fractures (CMC, MP, PIP joints) Unstable segmental fractures (pathologies unknown) Open fractures (gunshot wounds) Crush injuries Soft-tissue loss Posttrauma reconstruction Malunion/nonunion Arthritis Instability Contracture Deformity Amputation Burn reconstruction Contracture Deformity Amputation Congenital hand deformity Symbrachydactyly Transverse terminal arrest

Hypoplastic thumb Complex syndactyly (Apert's syndrome) Radial clubhand Contractures P.128

Acute Trauma In the setting of acute trauma, indications for external fixation can include unstable intra-articular fractures involving the proximal interphalangeal (PIP), metacarpophalangeal (MP), and carpometacarpal (CMC) joints (Fig. 10-1; Video 10-1). They may also include unstable segmental fractures with or without bone loss, open fractures, crush injuries, or injuries with soft-tissue loss (skin, tendon, and muscle injury) (Fig. 10-2; Video 10-2). Some contaminated wounds may present P.129 P.130 P.131 indications for external fixation to be used as a spanning apparatus until definitive internal fixation can be performed pending wound care, debridement, and resolution of potential infection (Fig. 10-3; Video 10-3). Areas of traumatic or burn loss of skin and subcutaneous tissue can be bridged and position maintained pending adequate coverage (Fig. 10-4; Video 10-4). Combinations of joint, tendon, burn, and soft-tissue injury may also be managed by means of dynamic fixation, which allows some degree of tendon excursion avoiding adhesions and contractures during the early healing phases (Fig. 10-5; Video 10-5) (4,11).

FIGURE 10-1 Miniaturized external fixation can provide a wide area of application throughout the hand. This includes stabilization of fractures and dislocations across the CMC joints (A,B). Applications across fractures and dislocations of the MP joint (C,D) and across the PIP joint (E,F) where fractures and/or fracture dislocations may be well stabilized by a combination of external fixation and limited internal fixation.

FIGURE 10-2 Open fractures with comminution and surrounding soft-tissue injury (A-D), gunshot wounds with bone loss (E,F), and in certain cases of tumor with pathologic fracture requiring grafting and spanning stabilization (G-J).

FIGURE 10-2 (Continued)

FIGURE 10-3 In the face of severe open trauma with loss of soft tissue and bone and potential contamination/infection, a complex external fixation system can be designed to allow for debridement, soft tissue revascularization, and allow access for wound care to allow secondary reconstruction once the environment has been declared viable. External fixation utilizes the principles of “ligamentotaxis” whereby the soft-tissue envelope is tensioned around the skeletal architecture to both mold the fragments into place and provide tension on the tendinous, muscular, and ligamentous structures providing a physiologic environment P.132 so as to minimize contracture and adhesions. The principle, however, does not ensure fine fragment realignment in the face of intra-articular fractures and therefore may need to be augmented by means of fine fragment realignment using various forms of internal fixation, intercalary support, or subchondral support in the face of loss of bone stock through bone grafting (Fig. 10-6; Video 10-6) (5,8,9,10).

FIGURE 10-4 In the face of severe burns with loss of substance (A-C), soft-tissue coverage is obtained when external fixation can be used to both stretch contracted soft tissues and perform callotasis lengthening of the remaining skeletal parts (D-F) and ultimately functional digital prehension (G-I).

FIGURE 10-4 (Continued) P.133

Posttraumatic Reconstruction The outcome of trauma may result in malunion or nonunion, posttraumatic arthritis, joint instability, contracture, or amputation. Indications for use of external fixation in posttraumatic reconstruction include providing stable fixation for realignment and osteotomy; compression arthrodesis, which leaves no long-term hardware in place; transarticular stabilization in conjunction with ligament reconstruction; slow distraction of severe contractures; and distraction lengthening of an amputated thumb or multiple digits (11,12,13,14,15,16) (Figs. 10-7A and 10-8; Videos 10-7 and 10-8).

FIGURE 10-5 Custom additions to external fixation include hinges, which can be centered over the center of rotation of a joint as seen clinically (A-C), and in postoperative video showing dynamic excursion of an MP joint, which has been reconstructed due to severe capsular and ulnar collateral ligament rupture. P.134

FIGURE 10-6 Periarticular fractures frequently require fine fragment approximation using augmentation techniques with K-wires, screw fixation, and bone grafting (A-E). Successful management of these periarticular fractures provides an excellent functional outcome (F,G). P.135

FIGURE 10-7 External fixation can also be used to control rotational and angular realignment in conjunction with osteotomy of deformity such as seen in this child having undergone prior complex syndactyly release who has significant functional malalignment of the central two fingers (A). A planned rotational angular correction can be seen based on the alignment of the fixator pins inserted before osteotomy and following realignment (B). Similar correction is performed in the shortened and deformed ring finger (C). Final alignment with restoration of normal cascade is seen in (D) and (E). Once the fixator is aligned, compression can be achieved across the fixator to enhance healing of the osteotomy, much as it can in an arthrodesis. (F) through (K) demonstrate surgical technique of exposure, denuding the articular surfaces, and compression arthrodesis of a thumb MP joint with good early function during the healing phase (L). P.136

FIGURE 10-7 (Continued) P.137

FIGURE 10-8 Distraction lengthening can provide both stabilization and creation of elongated functional length digits once soft-tissue coverage has been achieved (A-D). During the process of distraction lengthening and consolidation of the new bone that is forming in the distraction gap functional hand use is learned, guided by our hand therapists (E-H). P.138

FIGURE 10-8 (Continued) P.139 In all these cases, the external fixation apparatus acts as a stable bridge or self-limited traction system, which is quite sturdy and supports the complexities of multiple joint control through the interaction of extrinsic and intrinsic musculotendinous excursion across the injured area allowing joint mobility of adjacent articulations and ligamentous flexibility. It is indicated in conditions where other alternative forms of fixation may not provide ideal stability (K-wires, interfragmentary screws, plate and screw fixation, and intramedullary fixation).

Burn and Congenital Hand Reconstruction In patients who are born with congenital hand differences, such as symbrachydactyly, transverse terminal arrest, hypoplastic thumbs, or complex syndactyly with failure of formation of parts, external fixation techniques can be utilized applying the techniques of callotasis or distraction lengthening to elongate small digital remnants to form functional digits for purposes of sensate prehension (Fig. 10-9; Video 10-9) (12,16,17,18,19,20,22,23,24). It may also be utilized for angular and rotational deformity correction and syndactyly releases or for soft-tissue stretching and distraction following burns or in cases of severe radial clubhand about the deformed, contracted wrist in preparation for centralization or radialization procedures (Fig. 10-10; Videos 10-10A through 10E) (25).

FIGURE 10-9 Use of external fixation for distraction lengthening can be used to provide functional length following toe phalanx transfer in areas of hypoplasia and construction of a functional, sensate, prehensile hand as in this young child with severe symbrachydactyly and hypoplastic thumb who has undergone multiple toe phalangeal transfer of the index metacarpal and distraction lengthening resulting in a functioning prehensile hand (A-L). P.140

FIGURE 10-9 (Continued) P.141

FIGURE 10-9 (Continued) P.142

FIGURE 10-10 A child with severely hypoplastic (3B) thumb (A) has undergone two toe phalanx transfers followed by distraction lengthening (A-C). During the lengthening process, the child learns to use the reconstructed thumb (D). P.143

FIGURE 10-10 (Continued) Six years later after fine plasty and transfer of the flexor digitorum superficialis of the ring finger to FPO and extensor indicis proprius to EPO, the patient demonstrates a very functional stable thumb (E-H). P.144

FIGURE 10-10 (Continued) The video and multiple images are seen of young children following toe

phalangeal transfers and distraction lengthening of multiple digits. The children demonstrate just how dexterous they can be even when substantial skeletal architecture is missing from the beginning. Severe radial clubhand in a neonate can be managed with slow distraction and centralization (I,J) providing early realignment of the hand and wrist on the forearm with ability to perform functional activities at a young age.

CONTRAINDICATIONS Contraindications to the use of external fixation of the hand include conditions of gross infection, poor bone stock, or a suspected noncompliant patient who will not be able to participate in the needed degree of self-care following surgery (1,2,3,4,11). It is extremely important for the surgeon to undertake careful discussions with the patient and/or patient's family regarding the need for postoperative compliance, including pin site care, active participation in a rehabilitation program, and avoidance of secondary injury or contamination. If this is not possible, external fixation should not be utilized. Contraindications Infection Poor bone stock Noncompliant patient or family

PREOPERATIVE PREPARATION Careful patient selection and education regarding patient participation in pin site care and a rehab program, the importance of hygiene, and avoidance of contamination are all paramount as a first step in preoperative preparation of the patient. The surgeon should carefully review x-rays and any other appropriate imagining studies to ensure a complete understanding of the skeletal and soft-tissue environment through which the external fixation apparatus will be applied. In addition, plans for appropriate wound closure, soft-tissue coverage, tendon repair and excursion, as well as need for fine fragment augmentation with internal fixation (K-wires, interfragmentary screws, suture anchors) need to be planned out carefully preoperatively so all needed instrumentation is available at the time of surgery. A surgical approach through safe planes should be designed to allow easy access to intact structurally sound segments of bone for fixator pin insertion and external frame assembly, which will not interfere with surrounding hand function (1,2,3,11). A system should be utilized that affords flexibility in predrilling, insertion of secure self-tapping threaded half pins, and multiple options in frame configuration, while allowing radiographic access to the area of reconstruction (1,2,3,8,9,11). Based on the pathology at hand, a surgeon should also plan for the duration of fixation, when device removal is anticipated; how to optimize the rehabilitation program; and whether secondary surgical procedures may be needed so that the patient can be adequately prepared for the journey ahead. Preoperative Planning Careful patient selection. P.145 Patient education/preparation.

X-ray/imaging study review. Understand soft-tissue environment. Plan for additional internal fixation/bone graft. Know the anatomy and “safe planes.” Choose a flexible/user-friendly system. Have mini-image fluoroscopy readily available.

SURGICAL TECHNIQUE External fixation of the hand requires a good knowledge of anatomy, especially the anatomy of the extensor mechanisms of the hand and fingers. In almost all cases, the plan of approach for insertion of the external fixator pins will fall between the dorsal and lateral planes. Rarely will the plane of insertion be a direct central dorsal or central lateral plane, but rather an in-between (dorsal lateral) plane. The safest approach is through a limited open incision (26). This allows visualization of adjacent tendon structures, providing ability to retract them and/or create a small longitudinal split in them to ensure excursion of the extensor tendon during the healing process. It also permits visualization of intrinsic muscles to avoid injury and ensures central pin insertion to avoid damage to the small bones of the hand by means of avoiding creation of scarring and open-section defects. Predrilling provides a pilot hole for the insertion of self-tapping threaded half pins centrally located in the bone. This minimizes heat generation and therefore potential for bone necrosis, pin loosening, and infection (27). Pins should be inserted in a plane that minimizes obstruction or movement of adjacent fingers. In intra-articular comminuted fractures, external fixation can be combined with fine fragment control by augmenting with limited internal fixation (fine K-wires or minifragment screws). The fine fragment fixation allows precise restoration of articular congruity, while the spanning external fixator provides overall alignment and rotational and angular control and stability (4,11). This allows adjacent joint motion and tendon glide. Relaxing incisions can be made in the extensor mechanism overlying the proximal or middle phalanges, the tendon can be retracted, and after predrilling and pin placement, tendon glide and adjacent joint motion should be checked prior to closure. Once the fixator pins are in place, the surgeon can opt to perform fine fragment fixation, insert bone graft as needed for subchondral support, and then assemble and secure the entire fixator construct after first closing the incision with sutures. Nonabsorbable sutures are recommended in adults, while absorbable plain gut sutures are advisable in children. Proximally in the metacarpals or carpal bones, a small longitudinal incision can allow for visualization and retraction and ensure central placement of the fixator pins through a very limited incision. Again, closure before assembly of the entire construct adds to the ease of the procedure (Video 10-11AP). When the device is to be used for compression arthrodesis, pins should be placed on either side of the joint to be compressed, the joint surface prepared (either cup and cone or creation of two opposed flat surfaces with preplanned angular cuts), and the joint surfaces opposed and provisionally held with a central K-wire. Predrilling and insertion of fixator pins and closure of the incision are then performed, and the longitudinal rod is fixed to the fixator pins through connecting pin terminals. Once aligned longitudinally at the proper orientation to prevent angulation in the medial lateral plane with the desired amount of flexion built in, compression can be achieved across the arthrodesis site by means of clamp compression along the long axis of the connecting fixator bar. Some mini-fixator systems, such as Stryker's MicroFix (Stryker, Mahwah, NJ), offer radiolucent, very strong carbon fiber connecting rods of various lengths, which ensure full visualization during assembly with the fluoroscope and postoperatively for standard radiographs. This technique also allows secondary compression if needed at the first postoperative visit by loosening and recompressing (28).

Once the final compression across the arthrodesed joint is performed (whether this is performed intraoperatively or postoperatively), the central guiding K-wire is removed. In cases of stabilization during ligament repair or reconstruction (gamekeeper's thumb), ligamentotaxis can be achieved to provide appropriate tension on the healing capsule and ligaments to avoid postoperative contracture and allow early joint mobilization when the soft tissues have fully healed. In some cases, centrally placed hinge mechanisms may afford the ability to allow the injured joint to go through a limited arc of motion during the healing process (Video 10-12) (11). A combination of ligamentotaxis across the healing joint combined with outrigger fixation and support of adjacent segments can provide dynamic excursion of adjacent repaired tendons. This requires creative adaptation of extensions to the external fixator in conjunction with “creative hand therapists” (Fig. 10-11; Video 10-13A,B) (6,11,29). In patients with burn contractures and for distraction for creation of functional length segments in patients following traumatic amputation and in children with congenital hand differences, various forms of slow distraction have been employed to gradually open contracted areas and functionally lengthen bone remnants in conjunction with syndactyly release, and in some cases following prior transplantation of bone after it has revascularized (Fig. 10-12; Video 10-14) (4,11,25,30,31). P.146 P.147 P.148 P.149 External fixation pins can be used as alignment guides in cases of malunion when 3-dimensional corrective osteotomy is to be performed (32).

FIGURE 10-11 A comminuted intra-articular osteochondral fracture of the metacarpal heads of the midline ring fingers is seen following high-speed trauma (A). The extensor tendons have been ruptured and there is some degree of local skin loss (B). The osteochondral fragments are too small to hold with rigid fixation and have been sutured back into place with absorbable sutures. Following extensor tendon repair and grafting from adjacent fingers and wound closure with rotation flaps, the MP joints are held with gentle ligamentotaxis using spanning fixators to traverse the metacarpal phalangeal joints. Outrigger extensions have been fabricated by our hand therapists with dynamic extensor slings to rule out tendon excursion through PIP and DIP motion (C-F). The patient can be seen exercising with the device 6 weeks postoperatively when the external fixator is removed. His subsequent motion is near full as seen at 3 months postoperatively.

FIGURE 10-12 In severely hypoplastic hands where there is only a remnant of thumb and digits, web space creation and development of a reasonably functional thumb post and digits, which have sensation, and prehension can be developed with transplantation of an index metacarpal remnant to the thumb position creating a widened first web space, transplantation of toe phalanges, and secondary distraction lengthening to create a functional prehensile hand (A-L).

FIGURE 10-12 (Continued)

FIGURE 10-12 (Continued)

PEARLS AND PITFALLS Pearls Visualize the bone where fixator pins are to be inserted (small longitudinal incisions). Identify overlying extensor tendon and retract or locally split to ensure tendon gliding and movement of adjacent joints. Predrill the bone (ensures central placement and avoids further injury from soft tapping pins). Check depth of fixator pin with mini-image fluoroscopy (avoid overinsertion of pins, but make sure there is full thread purchase in both cortices). Use self-tapping threaded half pins of appropriate length to ensure adequate extension outside the skin for application of connectors and for access for wound and pin site care. Allow 1 week in a soft dressing for swelling and initial postoperative discomfort to resolve. Commence active finger mobility within the soft dressing immediately. Allow 1 week of rest between surgery and commencement of distraction lengthening. Once distraction has begun, it should be performed slowly (0.25 mm increments four times a day). We recommend the lengthening to be performed at breakfast, lunch, dinner, and bedtime. When a dynamic fixator (adoptive hinges and dynamic outrigger elastic supports) are utilized, such dynamization should be initiated when it is felt the primary site of injury is stable enough to allow it (usually 1 to 3 weeks). Pitfalls Avoid percutaneous pin insertion. Tendon “skewering” and tethering. This prevents adjacent joint mobility and tendon excursion, which results in pain and contracture. Avoid eccentric drilling and placement of pins, which can cause weakening and fracture through creation of open-section defects resulting in loss of fixation. Avoid inadequate fixation, which result in loosening, increased swelling, and infection.

Avoid self-drilling self-tapping pins (these have a tendency to burn the bone; the nonfluted cutting trocar has no threads and requires deeper placement to gain thread purchase on the far P.150 cortex resulting in potential injury to important soft-tissue structures and tendon nerve artery) on the far side of the bone. Avoid through-and-through fixation (this tends to interfere with adjacent digit excursion). Avoid assembling the device prior to wound closure (adds technical difficulty to the procedure). When fine fragment approximation is needed, don't hesitate to add limited internal fixation as needed. Don't expect the external fixator to provide such fine fragment realignment. Do not use this technique in a noncompliant patient (careful patient assessment and education are mandatory). Employing this technique in a noncompliant patient can result in disastrous complications despite meticulous surgical technique.

POSTOPERATIVE MANAGEMENT A bulky soft dressing should be used for the 1st week to provide support and limit posttraumatic/postoperative swelling. However, it is recommended that the therapist educate the patient preoperatively and on the day of surgery involving the importance of engagement in the rehabilitation program. Gentle movement of the adjacent joints and overlying tendons from day 1 is extremely important. At 1 week postoperatively, the soft dressing is removed, and the patient is instructed regarding adjacent joint mobility and tendon excursion exercises and in pin site care (in the case of children, parents are instructed in pin site care). Pin site care includes twice daily cleansing with a sterile Q-tip and hydrogen peroxide to break up crusts of blood and serum, which form along the fixator pin at the site of entry. This is continued for 1 to 2 weeks. We have found that more than twice a day cleansing can create hypertrophic granulation tissue and irritation and less than twice a day allows the buildup of subcutaneous serum, which can then result in the local pin tract infection. After 1 to 2 weeks of twice a day cleaning with peroxide, when the skin is fully healed and closed around the fixator pins and there is minimal serum formation, the cleansing can be changed to twice a day with rubbing alcohol in place of the peroxide. This provides a very clean and dry entry site. At this point, sutures are removed and the absorbable sutures have dissolved in children. We now allow patients to get the fixator wet with clean running water (no immersion) in the shower once a day and followed immediately by one of the alcohol cleanings (Fig. 10-13; Video 10-15A,B) (11,24,25).

FIGURE 10-13 The key part of the postoperative rehabilitation is active range of motion as seen in this woman who has had excision of a tumor and intercalary bone grafting. Twice a day diligent pin site care first with hydrogen peroxide and then with alcohol after 2 weeks remain a key part of the patient's responsibility (A-C). P.151 Regular therapist visits are recommended to ensure progression of mobility of the adjacent joints and stability of the area of repair/reconstruction. In cases of distraction lengthening, weekly return visits to the surgeon are accompanied with weekly radiographs to ensure the proper progression. After desired functional length has been achieved, a period of consolidation is required for new bone to form a distraction gap. This usually requires two times the duration of distraction in children and three times the distraction in adults. Radiographic assessment of new bone filling distraction gap and formation of new cortical bone on at least 3 sides suggests adequate structural integrity to allow removal of the external fixator/distractor (23,24,25). Removal of the device is performed in the clinic setting in adults, while most children under the age of 12 will require brief general anesthesia for comfort and compliance during removal. In some cases, after fixator removal, temporary splinting may be added to provide additional support to the healing structures while continuing to allow adjacent joint mobility. Key points in postoperative management Soft-tissue dressing 1 week. Pre-op and immediate post-op commencement of instruction and education and adjacent joint mobility and tendon glide. At 1 week, begin pin site care with dilute peroxide two times daily. 2 to 3 weeks post-op, advance to two times daily cleaning with rubbing alcohol. Once a day showering will be allowed at 2 to 3 weeks. Office removal of external fixator in adults. 4 to 6 weeks trauma to allow bone healing.

6 to 8 weeks tendon or ligament healing. Consolidation (minimum two to three times duration of lengthening) when callotasis distraction is employed. Regular hand therapy follow-up. Careful communication between therapist and surgeon.

COMPLICATIONS The most common complication of external fixation is local pin tract infections. These begin with some redness and local drainage. In the vast majority of cases, they can be managed with the use of a course or oral antibiotics and enhanced local pin site care. Other complications include contracture, stiffness, fracture around pin site, loosening and failure of the external fixation construct, nonunion of the fracture/arthrodesis/new bone regenerate, and deep infection (12,24,25). The likelihood of these complications occurring is greatly minimized by following the guidelines outlined in the pearls and pitfalls section.

RESULTS The use of ligamentotaxis to provide gentle physiologic transarticular soft-tissue tension allows restoration of functional mobility across injured joints. Use of the external fixator to provide stability during soft-tissue healing allows adjacent joints to remain mobile and overlying tendons to maintain their gliding capacity and avoid adhesions and contractures. Fracture and bone healing can occur physiologically in a stable environment due to the structural soundness of the external fixation construct. Restoration of functional length of digits and restoration of functional web space, especially between the thumb and index, is readily achieved through the technique of distraction lengthening. Restoration of function is the key element to using this technique in both children and adults (Fig. 10-14; Video 10-16) (11,22,23,24,25,30,31). P.152

FIGURE 10-14 Posttraumatic stabilization of fracture dislocations similarly is treated with the stability of an external fixator and allows early excursion of the surrounding tendons and intrinsic muscles, which then achieve functional outcome following removal (A-D).

REFERENCES 1. Seitz WH Jr, Gomez W, Putnman MD, et al.: Management of severe hand trauma with a mini external fixateur. Orthopedics 10: 601-610, 1987. 2. Putnam MD, Seitz WH: Advances in fracture management in the hand and distal radius. Hand Clin 5: 455470, 1989. 3. Alexander VA, Seitz WH Jr: Current trends and uses of external fixation in the hand and carpus. Curr Opin Orthop 8(IV): 1-6, 1997. 4. Seitz WH Jr, Froimson AI, Leb R, et al.: Augmented external fixation of unstable distal radius fractures. J Hand Surg 16A: 1010-1016, 1991. 5. Hochberg J, Ardenghy M: Stabilization of hand phalangeal fractures by external fixator. W V Med J 90: 5457, 1994. 6. Patel MR, Joshi BB: Distraction method for chronic dorsal dislocation of the proximal interphalangeal joint. Hand Clin 10: 327-337, 1994. 7. Buchler U: The small AO external fixator in hand surgery. Injury 25(Suppl 4): D55-D63, 1994.

8. Asche G: Possibilities for stabilization of an intraarticular comminuted fracture of the first metacarpal: use of the external mini fixator. Handchir Mikrochir Plast Chir 13(3-4): 247-249, 1981. 9. Riggs SH Jr, Cooney WP III: External fixation of complex hand and wrist fractures. J Traumatol 23(4): 332336, 1983. 10. Bilos ZJ, Eskestrand T: External fixation in comminuted gunshot fractures of the proximal phalanx. J Hand Surg [Am] 4(4): 357-359, 1979. 11. Goldberg SH, Seitz WH Jr: Management of complications following metacarpal and phalangeal fractures and dislocations. In: Seitz WH Jr, ed. Fractures and dislocations of the hand and fingers. Chicago, IL: American Society for Surgery of the Hand, 2013. [e-book]. 12. Seitz WH Jr, Froimson AI: Callotasis lengthening in the upper extremity. Indications, techniques and pitfalls. J Hand Surg [Am] 16A: 932, 1991. 13. Matev IB: Thumb reconstruction through metacarpal bone lengthening. J Hand Surg [Am] 5: 482, 1980. 14. Matev IB: First metacarpal lengthening for thumb reconstruction. Orthop Travmatol Protez 6: 11, 1969. 15. Kessler J, Baruch A: Experience with distraction lengthening of digital rays in congenital anomalies. J Hand Surg [Am] 2: 394, 1977. 16. Seitz WH Jr, Dobyns JH: Digital lengthening with emphasis on distraction osteogenesis in the upper limb. Hand Clin 9: 699-706, 1993. 17. Seitz WH Jr, Froimson AI: Digital lengthening using the callotasis technique. Orthopedics 18: 129-138, 1995. P.153 18. Heitman C, Levin LS: Distraction lengthening of thumb metacarpal. J Hand Surg 29B: 71-75, 2004. 19. Toh S, Narita S, Arai K, et al.: Distraction lengthening by callotasis in the hand. J Bone Joint Surg 84B: 205-210, 2002. 20. Houshian S, Ipsen T: Metacarpal and phalangeal lengthening by callus distraction. J Hand Surg 27B: 1326, 2002. 21. Ogino T, Kato H, Ishii S, et al.: Digital lengthening in congenital hand deformities. J Hand Surg [Am] 19B: 20-129, 1994. 22. Seitz WH Jr, Bley L: Distraction lengthening in the hand using the principle of callotasis. In: Raskin KB, ed. Atlas of the hand clinics. Philadelphia, PA: WB Saunders, 2000: 31-39.

23. Miyawaki T, Masuzawa G, Hirakawa M, et al.: Bone lengthening for symbrachydactyly of the hand with the technique of callus distraction. J Bone Joint Surg 84A: 986-991, 2002. 24. Seitz WH Jr, Shimko P, Patterson RW: Long term results of callus distraction lengthening in the hand and upper extremity for traumatic and congenital deficiencies. J Bone Joint Surg Am 92(Suppl 2): 47-58, 2010. 25. Seitz WH Jr: Distraction lengthening in the hand and upper extremity. In: Green DP, ed. Operative hand surgery. 6th ed. New York, NY: Churchill Livingstone, 2010: 1483-1502. 26. Seitz WH Jr, Putnam MD, Dick HM: Limited open surgical approach for external fixation of distal radius fractures. J Hand Surg 15A: 288-293, 1990. 27. Seitz WH Jr, Froimson AI, Brooks DB, et al.: External fixator pin insertion techniques: biomechanical analysis and clinical relevance. J Hand Surg [Am] 16(3): 560-563, 1991. 28. Seitz WH Jr, Sellman DC, Scarcella JB, et al.: Compression arthrodesis of the small joints of the hand. Clin Orthop Relat Res (304): 116-121, 1994. 29. Alison DM: Fractures of the base of the middle phalanx treated by a dynamic external fixation device. J Hand Surg [Am] 21B: 305-310, 1996. 30. Netscher DT, Lewis EV: Technique of nonvascularized toe phalangeal transfer and distraction lengthening in the treatment of multiple digit symbrachydactyly. Tech Hand Up Extrem Surg 12: 114-120, 2008. 31. Patterson RW, Seitz WH Jr: Nonvascularized toe phalangeal transfer and distraction lengthening for symbrachydactyly. J Hand Surg [Am] 35(4): 652-658, 2010. 32. Seitz WH, Froimson AI: Management of malunited fractures of the metacarpal and phalangeal shafts. Hand Clin 4: 529-536, 1988.

Chapter 11 Diagnostic and Therapeutic Approaches to the Boutonniere Deformity Neal B. Zimmerman Ryan M. Zimmerman Rebecca J. Saunders Michael A. McClinton

IDENTIFICATION OF THE BOUTONNIERE DEFORMITY The normal extensor mechanism is composed of an interconnected network of the subdivisions and reinforcing structures of the extensor mechanism surrounding the proximal interphalangeal (PIP) joint. Just proximal to the PIP joint, the extensor mechanism divides into three components. The central slip continues distally to insert into the base of the middle phalanx. The other two limbs diverge from the central slip to insert in the lateral bands, which lie dorsal to the PIP joint center of rotation. The lateral bands are secured in position palmarly by the transverse retinacular ligaments and dorsally by the triangular ligament. Abnormalities of these structures are necessary components of a boutonniere deformity, as will be explained below. The transverse retinacular ligaments run P.156 palmarly from the lateral bands to the volar aspect of the PIP joint and the volar plate. The oblique retinacular ligaments arise from the volar aspect of the PIP joint and flexor sheath to pass dorsally and insert into the terminal tendon as it nears its insertion into the dorsal base of the distal phalanx. They are thought to link extension of the proximal and distal interphalangeal (DIP) joints. Distal to the central slip insertion resides the triangular ligament, a thin translucent sheet that passes over the dorsum of the middle phalanx and functions to tether the lateral bands in their normal dorsal position (Figs. 11-1, 11-2, 11-3 and 11-4). A wide variety of traumatic insults can disrupt the central slip insertion into the base of the middle phalanx. It is important to recognize that injury of the central slip of the extensor mechanism is not synonymous with a boutonniere deformity. Indeed, central slip injury is a necessary P.157 P.158 precursor, but alone does not create a boutonniere deformity. Other necessary components to the development of the deformity are palmar migration of the lateral bands and attenuation of the triangular ligament. Following injury of the central slip, if full motion of the digit is continued, as in a neglected or unrecognized injury, proximal migration of the central slip causes reactive overpull through the lateral bands in an attempt to extend the PIP joint. This results in attenuation of the triangular ligament and palmar migration of the lateral bands, which eventually migrate palmar to the axis of PIP joint rotation. Augmented pull through the lateral bands is also responsible for exaggerated extensor tone at the distal joint. As they migrate palmar to the axis of rotation of the PIP joint, the lateral bands reverse their effect and act as flexors rather than extensors of the PIP joint. The summation of these pathologic changes is the development of a boutonniere deformity, which is the subacute to chronic digital deformity of PIP extension lag with DIP hyperextension (Fig. 11-5).

FIGURE 11-1 Lateral (A) and dorsal (B) views of the digit showing components of the extensor mechanism. Structures involved in the pathophysiology of the boutonniere deformity are marked (*). (Illustration by Elizabeth Martin © 2011. Reprinted with permission from Green's Operative Hand Surgery. 6th ed. Philadelphia, PA: Elsevier, 2011.)

FIGURE 11-2 Lateral view of the PIPJ showing the central slip insertion, triangular ligament, terminal tendon, lateral band, and the transverse retinacular ligaments. (Illustration by Elizabeth Martin © 2011. Reprinted with permission from Green's Operative Hand Surgery. 6th ed.)

FIGURE 11-3 Dorsal schematic view of the PIPJ indicating components of the extensor mechanism. (Illustration by Elizabeth Martin © 2011. Reprinted with permission from Green's Operative Hand Surgery. 6th ed.)

FIGURE 11-4 Dorsal view of the PIPJ in a cadaveric specimen. (A) Central slip insertion into the base of the middle phalanx, (B) triangular ligament, (C) terminal tendon insertion into the base of the distal phalanx. (Photograph courtesy of Dr. Thomas M. Brushart.) The key to effective treatment of central slip disruption and avoidance of the development of boutonniere deformity is early recognition. Indeed, since the boutonniere deformity progresses from central slip injury to the complex deformity over time, this interlude allows the majority of cases to be treated without surgery. When the central slip is initially disrupted, there is no clinical deformity of the digit. The person is able to make a full fist and to extend the PIP joint, albeit with diminished extensor power, because the lateral bands are intact and still dorsal to the axis of rotation. The most effective way to screen for a central slip disruption is Elson's test (1,2). We recommend that this maneuver be performed on any patient who presents with a swollen, tender PIP joint following injury. The magnitude of trauma required to disrupt the central slip is highly variable, as is the mechanism of injury. Although boutonniere deformity is classically taught to be an injury involving forced flexion on an extended PIP joint, a different mechanism should not allay concern. An elevated index of suspicion should be held for any injury to the area of the PIP joint. Every finger sprain needs to be evaluated with this specific testing to evaluate the competence of the central slip. Elson's test is carried out by flexing the patient's finger to 90 degrees of flexion at the PIP joint. This is typically done using the edge of the exam table. The person is then asked to attempt forceful PIP extension while the examiner resists the person's extension effort. In the normal situation, substantial extensor tension is generated at the PIP joint with a very little force generated at the distal joint. This makes sense, because the extensor system is intact, and the lateral bands cannot extend the DIP joint without the central slip also extending the PIP joint, which is being blocked by the examiner. With disruption of the central slip, the opposite occurs. Diminished

extensor tone is seen at the PIP joint with prominent or even exaggerated extensor force at the distal joint. This finding is also commonsense, as the disrupted central slip can now retract further than usual, whether or not the PIP joint is blocked, transmitting force P.159 to the terminal tendon through the lateral bands (1,3,4) (Fig. 11-6). The pseudo-boutonniere deformity is caused by a hyperextension injury of the PIPJ resulting in a flexion contracture without injury to the central slip and resultant lateral band migration and tightening. This can lead to stretching of the central slip over time resulting in decreased PIP extension. Unlike the boutonniere deformity, there is no disruption of the extensor mechanism. Testing with Elson's maneuver will show good extension force at the PIPJ and little force at the DIPJ, as seen in the normal situation (5).

FIGURE 11-5 The pathomechanics of the development of a boutonniere deformity. After disruption of the central slip (A), the lateral bands migrate palmar to the axis of rotation of the PIP joint due to attenuation of the triangular ligament. Overpull through the lateral bands due to their new, volar position causes exaggerated extensor tone at the DIP joint and flexion of the PIP joint (B). (From Wolfe SW, Hotchkiss RN, Pederson WC, et al., eds.: Green's Operative Hand Surgery. 6th ed. Philadelphia, PA: Elsevier, 2011. With permission from Elsevier.)

FIGURE 11-6 Elson's test is carried out by flexing the PIPJ to 90 degrees, typically over a hard surface such as a table. The patient is then asked to attempt to extend his or her PIPJ. With an intact central sip (A), there is good extensor tone at the PIPJ and little extensor force generated at the DIPJ. If the central slip is disrupted (B), there is decreased extensor force at the PIPJ and prominent extensor tone at the DIPJ. The red dot indicates the center of rotation of the PIP joint. Note the position of the lateral bands palmar to the axis of rotation in B.

The differential diagnosis of a swollen, painful PIP joint includes central slip disruption, fracture (of either the bony portion of the middle phalanx encompassing the central slip insertion or elsewhere), collateral ligament injury, volar plate damage, capsular sprain, inflammatory or crystalline arthropathy, as well as infection.

PEARLS AND PITFALLS Acute central slip injury, the inciting factor in a boutonniere deformity, often presents with no clinical deformity. Disruption of the central slip may not be initially clinically evident and needs to be suspected and tested for. Examine every injured PIP joint using Elson's test to determine central slip integrity. Failure of the central slip leads to diminished extensor power at the PIP joint and increased extensor power at the DIPJ during Elson's test. Untreated central slip injuries result in volar migration of the lateral bands, attenuation of the triangular ligament, and development of the boutonniere deformity.

EARLY CLINICAL MANAGEMENT Each case of a suspected central slip injury should be evaluated radiographically, including orthogonal views of the injured digit, in addition to the clinical examination described above. The vast majority of acute and chronic boutonniere deformities can be treated nonsurgically with acceptable results. It is worthwhile to remember that a mild extensor lag at the PIP joint is commonly not a significant impediment to hand function as long as the person is able to make a nearly full fist with good strength. The overarching goal of all treatments for boutonniere deformities is to increase deficient extensor tone at the proximal joint and to decrease exaggerated extensor tone at the distal joint. P.160

Acute Osseous or Open Injuries Radiographs may demonstrate an injury to the PIP joint with an osseous fragment, which includes the central slip insertion. In these cases, the osseous fragment with the contiguous central slip is repaired if feasible with fine wires or sutures. If the fragment is very small or insufficient for secure fixation, the central slip can be isolated from the fragment and a bone anchor used to insert it into its normal position at the dorsal base of the middle phalanx. An open injury of the PIP joint with disruption of the central slip necessitates direct repair by any of a variety of direct tendon repair techniques or mobilization of local tissues such as the lateral bands, central slip, or a portion of the flexor digitorum superficialis tendon (Figs. 11-7 and 11-8) (6,7,8,9).

FIGURE 11-7 A variety of techniques can be used to repair an open injury to the extensor mechanism involving damage to the central slip. (From Wolfe SW, Hotchkiss RN, Pederson WC, et al., eds.: Green's Operative Hand Surgery. 5th ed. Philadelphia, PA: Elsevier, 2005. With permission from Elsevier.) P.161

FIGURE 11-8 A turnover flap can be used to reconstruct the central slip if there is loss, or insufficient tissue for direct repair, as described by Snow, 1973. (From Wolfe SW, Hotchkiss RN, Pederson WC, et al., eds.: Green's Operative Hand Surgery. 6th ed. Philadelphia, PA: Elsevier, 2011. With permission from Elsevier.)

Acute Closed Soft-Tissue Injuries and Chronic Boutonniere Deformities With a Supple PIP Joint If the injury presents acutely or chronically with a fully passively flexible PIP joint, a common protocol is to initiate treatment with a splint holding solely the PIP joint in full extension. The duration of splinting is variable but usually comprises 6 to 8 weeks of full-time splinting, followed by nighttime splinting for another 6 weeks. Coupled with full-time extension of the PIP joint, the patient is asked to actively flex the distal joint. This has the effect of bringing the lateral bands back dorsal to the axis of rotation of the PIP joint, which serves to stretch the transverse retinacular ligaments and preclude them from shortening which would trap the lateral bands volar to the axis of PIP rotation. It also stretches the oblique retinacular ligaments, thus decreasing the tendency for hyperextension of the DIPJ while promoting gliding of the lateral bands (Fig. 11-9). The early short arc motion (SAM) protocol can also be used in the management of closed supple boutonniere injuries. Evans treated 36 people seen within 3 to 4 weeks of injury. Patients were P.162 initially immobilized in casts for 2 to 3 weeks to reduce edema and improve passive PIP extension. Patients were asked to perform a 30- to 40-degree arc of active PIP flexion in therapy two times per week under direct supervision. The PIP was splinted in full extension at all other times. Patients were seen for 8 weeks, and the average PIP flexion at discharge was 92 degrees with an extension lag of -6 degrees. Average DIP flexion was 47 degrees (10). Utilization of the SAM protocol advocates for an earlier return to function by decreasing the duration of therapy due to the development of excessive stiffness caused by prolonged immobilization.

Relative motion splinting is another method to support central slip disruptions that can replace or follow a period of full-time PIP extension splinting. The biomechanics of relative motion flexion splinting are intriguing (11). A relative motion flexion splint maintains the MCP joint of the injured digit in 15- to 20-degrees of flexion relative to the other fingers, while allowing full active extension of the other MCP joints (Fig. 11-10). The flexed posture of the MCP joint serves to protect the nascent boutonniere deformity (12). With relative flexion of the MCP joint, the lateral bands relax because of decreased intrinsic tone. This allows the lateral bands to migrate dorsal to the PIP joint center of rotation when they are drawn distally by DIP flexion. Further, the long extensor tendons directly pull the lateral bands dorsally via the lateral slips, which are subdivisions of the extensor mechanism connecting the extrinsic extensors to the lateral bands (12). Conversely, when full MP extension is allowed, the lateral bands are pulled palmarly by augmented intrinsic muscle tone and tightening of the transverse retinacular ligaments. Also, the relatively lax extrinsic extensors relax their dorsal support on the lateral bands through the lateral slips. Relative motion flexion splint technique requires that the PIP joint can be passively extended to neutral. The relative motion flexion splint is used during the day and a static PIP extension splint at night. If loss of extension is noted with exercises during the day, intermittent use of a static PIP extension splint is recommended as well during the daytime. Several surgeons have reported P.163 generally favorable results following 6 to 8 weeks of full-time boutonniere splinting with 2 months of relative motion flexion splinting (11,12,13).

FIGURE 11-9 Showing a patient in a splint with the PIPJ in full extension flexing the DIP to stretch the transverse retinacular ligaments and encourage the lateral bands to remain dorsal to the axis of rotation of the PIP joint.

FIGURE 11-10 Photos of patient wearing a relative motion flexion splint of the ring finger, which maintains the MCPJ of the involved finger in a relatively flexed posture compared to adjacent digits.

Chronic Deformity With a Stiff PIP Joint

Surgical reconstruction of the chronic boutonniere deformity can only be considered in the presence of a supple PIP joint. If the PIP joint lacks full passive extension at presentation, initial treatment is therapy directed toward reestablishing a full arc of PIP joint motion. Patients who present with a fixed PIP flexion contracture greater than 30 degrees require serial casting until passive extension to neutral is obtained. Severely swollen joints usually respond well to the gentle circumferential pressure provided by casting. Patients need to be seen in therapy frequently to monitor the cast fit as edema subsides. Less severe contractures respond well to other methods of static progressive orthoses to increase PIP extension. Orthotic use or casting should be continued until neutral extension is achieved, or there is a plateau in passive extension. Once maximum extension has been achieved, the patient needs to be immobilized in the extended position for 4 to 6 weeks prior to gradual remobilization into flexion. Once active PIP flexion is initiated, it is important to monitor the effects of the flexion exercises on the patient's extension lag. Orthotic use between exercise sessions and at night is continued for an additional 6 to 8 weeks. PIP stiffness recalcitrant to therapy and splinting can be treated with capsulectomy and subsequent therapy to maintain motion. PIP contractures that persist after capsulectomy can be managed with implant arthroplasty or arthrodesis. If a significant extensor lag recurs following capsulectomy, full-time splinting is reinitiated. Often, at the conclusion of a prolonged course of splinting, the patient will be left with a mild extensor lag (often approximately 20 degrees) at the PIP joint. This degree of deformity is often acceptable to them if they are able to make a good fist. Also, discussion with the patient should include the information that even in a boutonniere deformity treated surgically, a 20-degree extensor lag with a good arc of flexion of the PIPJ is an acceptable result, which is not uniformly achieved (Fig. 11-11).

FIGURE 11-11 An algorithmic approach to the pre- and nonsurgical treatment of the acute and chronic central slip and boutonniere deformities. (Copyright © The Curtis National Hand Center, 2015.) P.164

Pearls and Pitfalls The majority of boutonniere deformities can be treated nonsurgically.

Bony or open injuries of the central slip insertion should be treated surgically. A minimum of 6 weeks of full-time PIPJ extension splinting is needed. The DIPJ should be actively flexed while the PIPJ is immobilized in extension. Mild extensor lag at the PIPJ is functionally well tolerated.

SURGICAL RECONSTRUCTION OF THE CHRONIC BOUTONNIERE DEFORMITY The literature, including many textbooks, abound with descriptions of numerous techniques to deal with the chronic boutonniere deformity. As is often the case when multiple options exist, none has been proven superior and the sheer number of options can readily obfuscate principles of treatment. What follows is the authors' preferred treatment algorithm and not a comprehensive historical review of options. Broadly, we prefer Curtis' staged approach (14) as outlined below. We suggest that as readers develop their own preferences, they maintain a standardized, sequential approach to these cases. We hope this approach guides readers in a logical approach to a challenging surgical problem. We consider a supple PIP joint to be an absolute prerequisite for surgery. If a 20- to 30-degree extensor lag in a supple digit is unacceptable to the patient, we begin with tenolysis of the central slip and transverse retinacular ligaments. We recommend an extensile dorsal approach to the PIP joint with the patient under local anesthesia to participate in the surgical procedure. Although these first steps may seem relatively minor, significant deformities can sometimes be corrected by this intervention alone. In his classic paper, Curtis et al. (1983) demonstrated correction of a 50-degree extensor lag using solely tenolysis (14). If an extensor lag persists, the next step is division of the transverse retinacular ligaments. This liberates the lateral bands from their stout volar tethers, hopefully allowing them to drift dorsal to the PIP axis of rotation and again function as extensors rather than flexors of the PIP joint. The patient is again asked to actively extend the joint and the procedure terminated if full extension has been restored. Should an extensor lag still persist, its magnitude determines the next step. If the deformity is less than 20 to 30 degrees, a distal extensor tenotomy, as popularized by Fowler (15,16), is a reliable and predictable procedure to regain some, but not usually complete extension of the PIP joint. This procedure, in essence, creates a surgical mallet finger. Although a mallet finger is mechanically created, a mallet deformity does not result due to the preservation of the oblique retinacular ligaments, which serve to link extension of the PIP joints and DIP joints. This procedure is composed of division of the extensor mechanism at the level of the junction of the proximal and middle thirds over the middle phalanx, distal to the triangular ligament. The oblique retinacular ligaments that extend from volar plate of the PIP joint to the distal joint are identified (if possible) and preserved. Once the extensor mechanism is divided, the entire extensor hood slides proximally, thereby increasing extensor tone at the PIP joint (Figs. 11-12, 11-13, 11-14 and 11-15). A residual extension lag at the PIP joint of greater than 30 degrees following division of the transverse retinacular ligaments obligates the surgeon to evaluate whether the central slip remnant is robust and long enough to mobilize and advance into the base of the middle phalanx. We are unaware of any objective methods to make this determination; it is instead based on the surgeon's judgment. If deemed possible, the central slip is mobilized and advanced 4 to 6 mm into the middle phalanx and secured with an osseous anchor. The lateral bands are then sewn loosely to one another and to the reinserted central slip (Fig. 11-16). In his classic paper, Curtis et al. (1983) reported the outcomes on 23 patients managed with this algorithm. Preoperative extension lag of 41 degrees was reduced to 10 degrees in seventeen patients who required tenotomy, and an extension lag of 55 degrees was improved to 17 degrees in six patients who required central slip reinsertion (14). Despite over 30 years since this paper was published, we are unaware of further work studying an algorithm (as opposed to an

application of a particular technique) for managing the boutonniere deformity (Fig. 11-17). Various methods of reconstruction exist if the central slip cannot be reinserted into the middle phalanx, either due to retraction or tissue loss. Urbaniak et al. used only local tissue for reconstruction. They recommended raising a double-layered flap of capsule and synovium at the PIP joint to augment the damaged central slip insertion. They reported good results in 8 of 13 patients, and their only poor result was in a patient with an intra-articular fracture (17) (Fig. 11-18). Littler recommended separating the lateral bands from the oblique retinacular ligaments and securing them to the attenuated central slip remnant (18) (Fig. 11-19). Matev divided both lateral bands, but at different levels. He transferred the shorter to the native central slip insertion and transposed the longer one P.165 P.166 P.167 P.168 P.169 to the contralateral terminal tendon insertion. This technique uses one lateral band to reconstruct the central slip and the other to lengthen (but not fully release, as occurs with a distal tenotomy) the terminal extensor tendon (19) (Fig. 11-20). Terrill and Groves reviewed 20 consecutive patients who underwent the Matev procedure slightly modified by their incision choice. Of note, 14 of 20 patients had supple PIP joints at the time of surgery while six had a PIP flexion contracture. Good or satisfactory results were achieved in 85% of the patients with supple PIP joints preoperatively and 67% of those with a preoperative PIP contracture (20). Littler also described the use of a free tendon graft through the distal portion of the intact extensor mechanism into the base of the middle phalanx to reconstitute the central slip (21) (Fig. 11-21). Li et al. (2014) compared central slip reconstruction using a turndown of native tissue versus palmaris graft and found the native tissue turndown was superior (22). For this reason and others, the authors do not recommend tendon grafting for reconstruction of the central slip unless there are no other reasonable options.

FIGURE 11-12 Fowler distal tenotomy for a mild boutonniere deformity. The tenotomy is carried out proximal to the triangular ligament to preserve the dorsal tether of the lateral bands. A: Location of the tenotomy distal to the central slip insertion maintaining the integrity of the triangular ligament. B: Proximal migration of the extensor hood. C: Rebalancing of the extensor apparatus after proximal migration of extensor hood.

FIGURE 11-13 The central slip insertion into the base of the middle phalanx is indicated by “C”; the location of the division of the extensor mechanism for a Fowler central slip tenotomy is indicated by the arrow. Note the triangular ligament (T) distal to the indicated tenotomy site.

FIGURE 11-14 The Penfield retractor is lifting the oblique retinacular ligament, which is seen inserting into the terminal extensor tendon. This structure is retained after a Fowler central slip tenotomy and is partly responsible for extension of the DIP joint.

FIGURE 11-15 A central slip tenotomy has been performed in this patient with a supple boutonniere deformity. The arrow indicates the tenotomy distal to the triangular ligament and the central slip insertion. “C” indicates the central slip insertion and “T” the triangular ligament.

FIGURE 11-16 A 20 year-old collegiate football player sustained an acute central slip injury that progressed to a chronic boutonniere deformity over several months as he completed the season before seeking treatment. A course of splinting was needed to obtain full passive extension prior to undergoing the surgical reconstruction shown above. A dorsal Brunner incision is outlined with the apex at the level of the PIP joint (A). A flap is elevated down to the retinacular layer and reflected to reveal the subluxated lateral band (asterisk) (B). The transverse retinacular ligaments are tenolysed and divided to liberate the lateral bands (asterisk) (C, D). After separating the lateral bands and incompetent triangular ligament, the avulsed central slip (double asterisk) is clearly seen (E).The native central slip insertion is roughened and insertion sites for two bone anchors are marked (F).

FIGURE 11-16 (Continued) Bone anchors are placed and sutures passed through the central slip in horizontal

mattress fashion (G). The sutures are tied, reducing the central slip to its native insertion (H). The lateral bands (asterisk) are reefed together, restoring their native, dorsal position (I). The resting posture of the finger reveals full PIP extension at the conclusion of the case (J).

FIGURE 11-17 Curtis' algorithmic approach to boutonniere reconstruction. Stages I and II consist of tenolysis of the central slip and transverse retinacular ligaments followed by division of the transverse retinacular ligaments if needed. Stage III is the Fowler tenotomy, and stage IV is mobilization and advancement of the central slip followed by dorsal imbrication of the lateral bands to the advanced central slip. (From Curtis RM, Reid RL, Provost JM: A staged technique for the repair of the traumatic Boutonniere deformity. J Hand Surg [Am] 8(2): 167-171, 1983. With permission from Elsevier.)

FIGURE 11-18 Urbaniak's technique of central slip reconstruction using joint capsule and local tissue illustrating elevation of a proximally based flap (A) and layering of this flap over tissue raised from the base of the middle phalanx (B). (From Urbaniak JR, Hayes MG: Chronic boutonniere deformity—an anatomic reconstruction. J Hand Surg 6(4): 379-383, 1981. With permission from Elsevier.)

FIGURE 11-19 Littler described division and dorsal transposition of the lateral bands to central slip remnant to increase extensor force at the PIP joint. (From Bates SJ, Chang J: Repair of the extensor tendon system. In: Thorne CH, Bartlett SP, Beasley RW, et al., eds. Grabb and Smith's Plastic Surgery. 6th ed. Philadelphia, PA: Lippincott Williams & Wilkins, 2006.)

FIGURE 11-20 Matev's technique to reconstruct the central slip involves dividing the two lateral bands at different levels (A). The shorter lateral band is attached to the remnant of the central slip insertion, and the longer lateral band is sutured to the contralateral terminal tendon (B). Ohshio et al. described using yet another tissue option for reconstruction: the transverse retinacular ligaments. They recommended release of the volar attachment of each transverse retinacular ligament and then flipping them dorsally and sewing them to one another. This forces the lateral bands to become extensors of both the PIP and DIP joints. Of note, loss of PIP flexion can occur with this technique, and it is contraindicated with

contracted lateral bands (23). Even more creatively, Ahmad rerouted a slip of the flexor digitorum superficialis tendon through the middle phalanx onto the dorsal surface and sewn to the proximal stump of the central slip (9). Of note, Klasson et al. (1992) evaluated biomechanically a number of chronic boutonniere reconstructions and found they were all similar and biomechanically sufficient. We agree with the authors that the preoperative status of the finger is likely a key determinant of surgical outcome (24) (Fig. 11-22). Although we advocate making the final decision of reconstructive technique intraoperatively after evaluation of the tissue available, we prefer the Matev technique (19) when the central slip cannot be reinserted and avoid the use of tendon grafts. The challenges of any soft-tissue procedure to reconstruct the extensor apparatus are proper balancing and knowing when sufficient correction has been achieved, and reconstruction of a chronic boutonniere is no exception. Surgeons have traditionally relied on their subjective judgment to determine the extent of soft-tissue releases needed P.170 P.171 to rebalance a boutonniere, manipulating the digit or observing the tenodesis effect or the resting cascade in a manner of personal preference. Recently, wide awake hand surgery (also referred to as wide awake local anesthesia no tourniquet or WALANT) has garnered significant attention and support as a way to obtain realtime feedback on procedures such as tendon repairs or transfers (13). Although we are unaware of any papers specifically discussing it, reconstruction of a chronic boutonniere may benefit substantially from these techniques (12).

FIGURE 11-21 Littler advocated using a free tendon graft to reconstitute the central slip if adequate local tissue is not present.

FIGURE 11-22 The authors' suggested algorithmic approach to surgical treatment of the boutonniere deformity. (Modeled after Curtis RM, Reid RL, Provost JM: A staged technique for the repair of the traumatic boutonniere deformity. J Hand Surg Am 8(2): 167-171, 1983. Copyright © The Curtis National Hand Center, 2015.)

FIGURE 11-23 The patient is performing short arc flexion and extension of the PIP joint with the help of a template splint. Central slip repairs, whether they are simple or complex injuries, are effectively managed using the SAM, or early SAM protocol (25). This protocol allows 30 degrees of active PIP flex with an active extension component within a few days of the operative procedure. Thirty degrees of motion was found to be great enough to prevent tendon adherence over the proximal phalanx without compromising the central slip repair integrity. Early motion is thought to prevent the deleterious effects of prolonged immobilization of the PIPJ. This technique has been shown to provide superior results in regard to total active range of motion, decreased extension lag, time to discharge from therapy, and earlier return to work for both simple and complex injuries when compared to the traditional management of immobilization for 6 to 8 weeks. Simple template splints are used to guide the patient in performing the correct amount of motion at each joint. The PIP is splinted in neutral at all times when not performing the prescribed exercises. The arc of motion for the PIP joint is increased 10 degrees each week after the 2nd postoperative week as long as the patient is not developing an extension lag. The arc of flexion is

increased by 10 degrees per week if the patient is able to maintain their active extension. The use of the PIP extension splint is weaned during the day between 6 and 8 weeks after surgery, and night splinting is continued for a few additional weeks (26) (Fig. 11-23).

PEARLS AND PITFALLS Follow an algorithmic approach to these challenging surgical reconstructions. Test digital motion frequently, ideally in a wide awake patient, after each stage of correction. We prefer Dr. Curtis' staged approach and use the Matev technique of lateral band divisions and transfers when the central slip cannot be reinserted. Patients should be counseled that a mild extensor lag or loss of flexion can be the final result after complex reconstruction. Surgeons should be wary of operating on patients with unrealistic expectations.

COMPLICATIONS Stiffness of the digit following either surgical or nonoperative treatment of the boutonniere deformity is by far the main complication. It is important to remember that a mild extensor lag is functionally far less of an impairment than a digit with limited flexion. Thus, attempts to increase extensor power at the PIP joint should be tempered with caution. P.172

REFERENCES 1. Elson RA: Rupture of the central slip of the extensor hood of the finger. A test for early diagnosis. J Bone Joint Surg (Br Vol) 68(2): 229-231, 1986. 2. Vermaak P, Devaraj V: Don't slip up! A modified technique for assessing central slip injuries. J Bone Joint Surg (Eur Vol) 37(9): 893-895, 2012. doi: 10.1177/1753193412439273 3. Rubin J, Bozentka DJ, Bora FW: Diagnosis of closed central slip injuries. A cadaveric analysis of noninvasive tests. J Hand Surg Br 21(5): 614-616, 1996. doi: 10.1016/S0266-7681(96)80142-2 4. Venus MR, Little C: The modified Elson's test in open central slip injury. Injury Extra 41(11): 128-129, 2010. doi: 10.1016/j.injury. 2010.08.039 5. McCue FC, Honner R, Gieck JH, et al.: A pseudo-boutonniere deformity. Hand 7(2): 166-170, 1975. 6. Green DP, Hotchkiss RN, Pederson WC, et al., eds: Green's Operative Hand Surgery. 5th ed. Vol. 1. Philadelphia, PA: Elsevier Churchill Livingstone, 2005: 200-203. 7. Snow JW: Use of a retrograde tendon flap in repairing a severed extensor in the pip joint area. Plast Reconstr Surg 51(5): 555, 1973. 8. Aiache A, Barsky AJ, Weiner DL: Prevention of the boutonniere deformity. Plast Reconstr Surg 46(2): 164167, 1970.

9. Ahmad F, Pickford M: Reconstruction of the extensor central slip using a distally based flexor digitorum superficialis slip. J Hand Surg Am 34(5): 930-932, 2009. doi: 10.1016/j.jhsa.2009.01.025 10. Evans RB: Clinical management of extensor tendon injuries: The therapist's perspective. In: Skervin TM, Osterman AL, Fedorczyk J, et al., eds. Rehabilitation of the Hand and Upper Extremity. 6th ed. Philadelphia, PA: Mosby, 2011. 11. Merritt WH: Relative motion splint: active motion after extensor tendon injury and repair. J Hand Surg Am 39(6): 1187-1194, 2014. doi: 10.1016/j.jhsa.2014.03.015 12. Lalonde DH: How wide awake surgery changed my practice. Curtis National Hand Center. 2014; 77 minutes. 13. Lalonde DH, Kozin S: Tendon disorders of the hand. Plast Reconstr Surg 128(1): 1e-14e, 2011. doi: 10.1097/PRS.0b013e3182174593 14. Curtis RM, Reid RL, Provost JM: A staged technique for the repair of the traumatic boutonniere deformity. J Hand Surg Am 8(2): 167-171, 1983. doi: 10.1016/S0363-5023(83)80009-4 15. Fowler SB: Fowler: extensor apparatus of the digits. J Bone Joint Surg Br 31:477,1949. 16. Houpt P, Dijkstra R, Van Leeuwen JS: Fowler's tenotomy for mallet deformity. J Hand Surg Br 18(4): 499500, 1993. 17. Urbaniak JR, Hayes MG: Chronic boutonniere deformity—an anatomic reconstruction. J Hand Surg Am 6(4): 379-383, 1981. doi: 10.1016/S0363-5023(81)80048-2 18. Littler JW, Eaton RG: Redistribution of forces in the correction of Boutonniere deformity. J Bone Joint Surg Am 49(7): 1267-1274, 1967. 19. Matev I: Transposition of the lateral slips of the aponeurosis in treatment of long-standing “boutonniere deformity” of the fingers. Br J Plast Surg 17: 281-286, 1964. 20. Terrill RQ, Groves RJ: Correction of the severe nonrheumatoid chronic boutonnière deformity with a modified Matev procedure. J Hand Surg Am 17(5): 874-880, 1992. 21. Littler JW: The digital extensor-flexor system. Reconstructive Plastic Surgery. Philadelphia, PA: W.B. Saunders Company, 1977: 3174-3175. 22. Li Y, Ding A, He Z, et al.: Comparison of proximal turndown of central slip combined with suture of lateral bands versus free tendon grafting for central slip reconstruction after an open finger injury. Acta Orthop Belg 80(1): 119-125, 2014. 23. Ohshio I, Ogino T, Minami A, et al.: Reconstruction of the central slip by the transverse retinacular

ligament for boutonnière deformity. J Hand Surg Br 15(4): 407-409, 1990. 24. Klasson SC, Adams BD: Biomechanical evaluation of chronic boutonnière reconstructions. J Hand Surg 17(5): 868-874, 1992. 25. McAuliffe JA: Early active short arc motion following central slip repair. J Hand Surg Am 36(1): 143-146, 2011. doi: 10.1016/j.jhsa.2010.10.007 26. Evans RB: Early active short arc motion for the repaired central slip. J Hand Surg Am 19(6): 991-997, 1994. doi: 10.1016/0363-5023(94)90103-1

Chapter 12 Strategies for Handling the Flexible Fixed Swan-Neck Deformity Kenneth Robert Means Jr

INTRODUCTION Swan-neck deformity of the fingers is defined as proximal interphalangeal (PIP) hyperextension and distal interphalangeal (DIP) flexion. Concomitant metacarpophalangeal (MCP) flexion deformity is possible though it is not a requisite feature. Fortunately, hand surgeons today do not frequently encounter debilitating swan-neck deformities in patients. This is especially true due to the recent advent of disease-modifying antirheumatic drugs (DMARDs) that have revolutionized the care of many rheumatologic conditions and prevented many crippling extremity deformities, including swan-neck posturing of the digits. Systemic lupus erythematosus (SLE) is the classic rheumatologic condition that causes flexible swan-neck deformities, but other conditions can lead to this problem as well (Fig. 12-1). Unfortunately, a lack of familiarity with swan-neck deformities on the surgeon's part may lead to uncertainty when treating patients with this potentially complex problem. This is likely particularly true for younger surgeons who may not have as much experience, due to the use of DMARDs, with the many possible presentations, pathologies, and treatment options for these deformities. Part of the challenge of treating patients with swan-neck deformity is that, unlike boutonniere deformity that by definition originates at the PIP joint, swan-neck deformity can originate at the wrist, MCP, PIP, or DIP joints, and often, there is pathology at more than one joint contributing to the deformity. One of the first things surgeons should try to determine when treating a patient with a swan-neck deformity is the underlying pathologic and anatomic cause of the deformity; knowing this will help guide treatment. Surgeons typically start correction of swanneck deformity at the most proximal involved joint and progress distally either at the same surgical setting or in stages. Today, hand care professionals are most likely to see patients present with swan-neck deformities as the result of trauma, such as a mallet finger injury or PIP joint dislocation. Swan-neck posturing after these types of injuries is typically not as severe as that with rheumatologic conditions. These patients may have clinically insignificant swan-neck posturing in which they are still able to actively initiate PIP joint flexion, and the deformity may be more of a cosmetic concern. In these cases, the main focus is on preventing worsening of the deformity, which could then lead to significant P.174 functional limitation. This entails the use of a PIP dorsal block or figure-of-eight splint to prevent hyperextension but still allow flexion. Intrinsic stretches are also helpful if the patient demonstrates significant intrinsic tendon tightness. The main functional limitation for patients with clinically significant flexible or fixed swan-neck deformity is their inability to flex the PIP joint. For patients with flexible deformity, this means that they have to use their other hand or place the dorsum of the affected digit against something in order to initiate active PIP flexion. For patients with fixed deformity, the PIP joint is by definition in a hyperextended and contracted position and unable to flex even passively beyond this point. Other causes of clinically significant swan-neck deformity include more severe trauma such as hand crush injuries with severe intrinsic contractures, burns with dorsal skin and softtissue contractures, neuromuscular conditions with hand intrinsic muscle spasticity and eventual joint contracture, and patients at varying places along the spectrum of generalized hyperextensibility. Evaluation and treatment of these more rare and specialized causes of swan-neck deformity are beyond the scope of this chapter.

FIGURE 12-1 Patient with SLE and several fingers with tendencies toward swan-neck deformity, most pronounced in the small finger where the patient is unable to actively initiate PIP flexion. There have not been many recent changes in the nonoperative and operative management of swan-neck deformity. Authors have reported recent results with different techniques as well as modifications to some of the techniques (1). In this chapter, I present what I believe to be the most effective surgical techniques for the most commonly encountered swan-neck pathologies. I have also sought the collective experience and wisdom from all of the surgeons at our hand center and will acknowledge many of their tips throughout the chapter to further this cause. I am of course also indebted to the authors of the excellent chapter in the previous edition of this text and draw on their observations and recommendations here as well (2).

INDICATIONS Patients with functional issues due to the swan-neck deformity for which splints are ineffective or impractical; in most cases, surgical intervention will not increase the overall range of motion for the finger but will make the range of motion take place in a more functional arc. Patients with progressive deformity that may lead to functional deficits; this involves more of a preventative approach, such as treating an acute or chronic mallet injury in order to prevent further progression of the swan-neck deformity. Patients with flexible deformities are, by definition, fully passively correctable; for these patients, softtissue reconstruction options are indicated. Patients with fixed deformities are indicated for joint release followed by soft-tissue reconstruction only if the articular surfaces are in acceptable condition. Arthrodesis or arthroplasty is indicated when the articular surfaces are not in acceptable condition.

CONTRAINDICATIONS Patients who cannot reliably follow postoperative instructions including a therapy protocol Patients with severe medical comorbidities or infection that preclude surgical intervention P.175

PREOPERATIVE PREPARATION The most important part of the preoperative preparation for patients with flexible swan-neck deformities is to

determine the primary, and any secondary, cause(s) of the deformity. This is typically achieved through a good history and physical exam. During the history, the surgeon should determine the timing and sequence of development of the deformity, any discrete pain locations, the presence of significant mechanical issues such as joint(s) locking or being unstable in certain positions, history of trauma or other surgical procedures, and how the deformity is impacting the patient's life. During the physical exam, the surgeon is looking for any joints that are synovitic from the wrist to the DIP joint, the resting and active posture of the digit including the joints that are most significantly contributing to the deformity, the condition of the skin and soft-tissue envelope for the finger, tenderness at any joints, the suppleness of any deformities, and any flexor or extensor mechanism abnormalities including assessment of extrinsic extensor or flexor tightness and utilizing the Bunnell test to reveal any intrinsic tightness. Providers should obtain x-rays of all the joints of the involved fingers as well as the hand and wrist of the patient. The classic and still most commonly used swan-neck classification scheme is that of Nalebuff where type I is a flexible PIP hyperextension deformity; type II is secondary to intrinsic tightness; type III is a fixed PIP joint extension contracture that is “intrinsic” to the joint itself, that is, the contracture does not change regardless of the degree of flexion or extension of the MCP or any other joints; and type IV is a swan-neck deformity associated with significant PIP joint degenerative changes. Of course, patients with rheumatologic conditions require special preoperative considerations, such as medication and cervical spine management, which are typically coordinated between the surgeon, rheumatologist, and anesthesia providers. At our institution, we have a protocol based on input from anesthesia, orthopedic spine surgery, and our hand center for cervical spine management: all patients with inflammatory arthropathies that may affect cervical spine stability obtain cervical spine x-rays consisting of A/P, lateral, and flexion and extension lateral x-rays a maximum of 1 year before a pending elective extremity surgery. We typically indicate on the x-ray prescription to include measurements of c1 to c2 translation, subaxial translation, or presence of basilar invagination. If any of the following are found on these screening films, then the patient is referred to a physician who treats cervical spine patients, such as PM&R or ortho/neurospine surgery, to determine if any further investigations/treatments are needed before proceeding with elective extremity surgery: subaxial translation of greater than 3 mm, c1 to c2 translation of more than 4 mm, and any degree of basilar invagination. Depending on the patient's overall presentation, extent of planned procedures, and other preoperative recommendations, surgeons may perform the swan-neck procedures under local or regional nerve block or via general anesthesia.

TECHNIQUE Procedures to Correct MCP-Primary Flexible Swan-Neck Deformity MCP-primary deformities typically present in patients with inflammatory arthropathies. In these cases, the MCP synovitis eventually leads to attenuation of the extensor hood, especially the radial sagittal band, and ulnar translocation of the extensor tendons. The proximal phalanx (P1) progressively migrates palmarly and ulnarly until the MCP joint is subluxated or even permanently dislocated in this position. As the extensor tendons become scarred in the ulnar gutter of the MCP joint and the base of P1, the MCP joint rests in a palmar-ulnar position leading to shortening of the extrinsic and intrinsic extensor mechanisms, especially on the ulnar side of the finger. This can lead to an increased PIP extension moment and an initially flexible swan-neck deformity. If the MCP disease is caught before it becomes a fixed situation, then surgical correction at this level may be enough to correct the swan-neck deformity and prevent it from worsening. However, the tendency toward swanneck posturing classically becomes accentuated when surgical attempts are made to correct a fixed MCP deformity. In these cases, MCP arthroplasty, by correcting the joint subluxation, often effectively lengthens the digit and consequently further tensions the shortened extrinsic and intrinsic extensor mechanisms. Centralizing the previously subluxated extensor tendon also increases the extension force at the PIP joint. The combination of these changes can worsen the swan-neck deformity (Fig. 12-2). In these cases, a central extensor tenolysis and

intrinsic release at the level of the lateral bands can help. If the deformity is still not corrected, one of the lateral bands may be excised, typically the ulnar side to help counter ulnar drift tendencies. If this still does not achieve correction, the surgeon may have to shorten the MCP arthroplasty by removing more distal metacarpal or more proximal P1. The goal at each stage of attempted correction is to not have a resting swan-neck deformity and for the surgeon to be able to easily passively flex the PIP joint whether the MCP joint is flexed or extended. P.176

FIGURE 12-2 Rheumatoid arthritis patient who previously underwent MCP silicone arthroplasties with extensor tendon centralization and subsequently developed a fixed swan-neck deformity of the ring finger.

Procedures to Correct PIP-Primary Flexible Swan-Neck Deformity Flexor Digitorum Superficialis Tenodesis of the PIP Joint In inflammatory arthropathies, the PIP joint can become synovitic with subsequent attenuation of the surrounding soft tissues, especially the volar plate or the dorsal extensor mechanism. If the volar plate is more significantly attenuated, then PIP hyperextension and swan-neck deformity ensue. If the dorsal extensor mechanism is more significantly affected, then a boutonniere deformity is the result and is covered elsewhere in this book. As the PIP joint hyperextends and the transverse retinacular ligament becomes attenuated, the lateral bands become centralized dorsally and lax, which results in less extensor force at the DIP joint. This, combined with unopposed and even increased flexion force from the increased tension on the flexor digitorum profundus (FDP), leads to the DIP flexion deformity. Flexor digitorum superficialis (FDS) tenodesis of the PIP joint is a simple and effective technique to correct a flexible PIP hyperextension deformity (E.F. Shaw Wilgis, MD and Neal B. Zimmerman, MD, personal communication) (3). The surgeon should use his or her preferred palmar approach to the finger; I favor a midaxial incision. The C1 and A3 pulleys over the PIP joint are removed. Excursion of the FDS and FDP can be checked at this point to ensure that a flexor tenosynovectomy or tenolysis is not required. One slip of the FDS is transected just distal to Camper's chiasm, leaving the middle phalanx (P2) insertion of the slip intact. The proximal end of the slip is then used to flex the PIP joint to a desired flexion position. We usually expect tendon transfers and tenodeses to stretch out over time, especially in patients with rheumatologic or other soft-tissue disorders. Therefore, a prudent amount of PIP flexion contracture is approximately 20 to 30 degrees to try to balance between preventing recurrence of the deformity and causing a functional limitation due to the contracture. When the desired degree of PIP flexion is achieved, the slip of FDS is sutured to the proximal phalanx (P1). Either the slip can be sutured to the edge of the flexor sheath or a suture anchor can be placed in the P1 to which the slip can be secured. A variation on this technique is similar to the Zancolli FDS volar MCP tenodesis, in this case transecting a slip of FDS, bringing it through a slit in A2, and suturing it back to itself distally in the desired PIP flexion position. However, that technique requires more dissection, may be more likely to stretch out over time, and may cause more adhesions in zone 2. Having said that, I have performed both procedures and both are certainly acceptable without any clear difference in outcomes in the reported literature; I agree with Dr. Wilgis and Dr. Zimmerman that the first technique is simpler and effective. In fact, this procedure can also be performed

in the palm with the FDS tenodesis occurring at the A1 pulley level (4). An advantage of using the slip of FDS rather than a PIP volar plate capsulodesis is that typically, the volar plate is attenuated due to the swan-neck deformity. A disadvantage of simply tenodesing the PIP joint in flexion is that although it may allow the lateral bands to be more lateral/palmar than central/dorsal, this may not be enough to correct a significant DIP flexion deformity. Lateral Band Relocation Another simple and effective treatment for PIP-primary flexible swan-neck deformity is to release and relocate the lateral bands, a procedure attributed to Zancolli. The surgeon uses his or her preferred approach to the dorsum of the finger. I favor an incision that is midaxial at the level of the PIP joint and then gently swings dorsal/central to the level of the base of P1 proximally and the head of P2 distally. A fullthickness skin and soft-tissue flap is elevated just above the extensor paratenon, while protecting the dorsal digital nerve branch. The skin can then be temporarily sutured to the other side of the finger for retraction (Fig. 12-3). The radial and ulnar lateral bands are then tenolysed at the level of the P1 and the PIP joint, incising between the lateral bands and the central extensor tendon (Fig. 12-4). Gentle manipulation of the PIP joint is then performed, and if the lateral bands are not mobile enough to slide palmarly, then they can be further released distal to the PIP joint. This should now allow the lateral bands to slide palmarly during PIP P.177 P.178 flexion provided that the PIP joint capsule and collateral ligaments do not limit flexion (Fig. 12-5A). If these procedures do not provide enough correction in passive flexion at the PIP joint, then partial collateral ligament releases and/or central slip lengthening can be performed as well. This alone may be enough to correct the deformity if a dorsal blocking splint is used postoperatively. However, to try to prevent recurrence of the deformity, I favor suturing one of the lateral bands to palmar tissue in the desired degree of PIP flexion, again typically 20 to 30 degrees. The lateral band can be sutured to the flexor sheath or via a suture anchor placed in P1, in either case, thus acting as a tenodesis. This procedure removes the hyperextension force that the lateral bands were exerting at the PIP joint, prevents at least one of the lateral bands from returning to a dorsal position, provides a passive check to PIP hyperextension, and, by leaving the other lateral band to lay in its resting position and keeping the central slip insertion intact, should prevent the development of a boutonniere deformity. A variation on this procedure is to create a soft-tissue flap that the palmarly translocated lateral band can potentially slide through while preventing dorsal translation. This entails using a portion of the flexor sheath to form the flap at the A3 level, placing the lateral band within this sling, and suturing the flexor sheath flap back on to itself to capture the lateral band. Alternatively, the lateral band can actually be sutured within the flexor sheath so that it lies alongside the flexor tendons at the A3 level (Fig. 12-5B). Yet another variation is to suture a portion of the flexor sheath to the volar plate to create the sling to capture the lateral band. If the skin is too tight and restricting PIP flexion, it can be left open at the end of the procedure over the distal portion of the incision (5).

FIGURE 12-3 Dorsal finger exposure for lateral band relocation and other procedures.

FIGURE 12-4 Lateral band releases.

FIGURE 12-5 A: Gentle PIP joint manipulation in flexion. B: Lateral band stabilization option that entails capturing the lateral band within the flexor sheath at the A3 pulley level.

Procedures to Correct DIP-PIP-Primary Flexible Swan-Neck Deformity Spiral Oblique Retinacular Ligament (SORL) Reconstruction Surgeons typically consider using this procedure for patients who have significant DIP and PIP flexible deformities in which correction of the PIP joint alone is likely to leave significant dysfunction. Several tendon transfer or free graft options have been described for this technique first attributed to Littler, but our preferred method is to use an ulnar lateral band tenodesis as long as it and the terminal tendon insertion are in good enough condition to do so (James P. Higgins, MD, personal communication). A curvilinear incision is made over the dorsalulnar aspect of the finger. The apex of the curved portion of the incision is over the ulnar aspect of the PIP joint, and the proximal and distal dorsal-central portions of the incision are at the mid-P1 and proximal-P3, respectively. A full-thickness skin flap is elevated over the paratenon of the extensor mechanism until reaching the radial border of the extensor mechanism. During this dissection, the dorsal ulnar digital nerve branch is identified and protected. At the level of the radial PIP/distal P1, the skin flap elevation should be such that the surgeon will be able to identify the radial palmar neurovascular bundle from the dorsum later in the procedure. The skin flap can then be sewn to the radial-palmar skin of the finger for retraction. The ulnar lateral band is dissected as a distally based flap of tissue on its insertion into the conjoined terminal extensor at the dorsal aspect of the distal phalanx by elevating it separately from the undisturbed radial component. This ulnar lateral band release is created longitudinally along the dorsal-radial edge of the lateral band and into the triangular ligament at the dorsal PIP joint, staying just ulnar to the central slip insertion. The proximal aspect of the ulnar lateral band is then transected at the base of the proximal phalanx and elevated distally, again keeping the distal terminal tendon insertion intact at the dorsal base of P3. A softtissue tunnel is created that passes between the ulnar digital neurovascular bundle and the flexor tendon sheath on the ulnar aspect of the middle phalanx. A second soft-tissue tunnel is created on the radial aspect of the finger at the level of the PIP joint, this time between the radial digital neurovascular bundle and the flexor sheath.

A long clamp or tendon passer is passed from the proximal-radial tunnel to the distal-ulnar tunnel, being careful to protect the neurovascular bundle at each location. The free proximal end of the ulnar lateral band is clamped, and the clamp and lateral band are withdrawn to the level of the proximal-radial tunnel at the PIP joint. In this way, the ulnar lateral band transfer does not compress the ulnar or radial neurovascular bundles and lies superficial to the flexor sheath. The transferred lateral band is then tensioned proximally to provide approximately 30 degrees of PIP flexion while keeping the DIP joint in neutral extension. When the desired position is reached, the transferred ulnar lateral band is secured to the radial aspect of the proximal phalanx with a suture anchor to maintain this same degree of tension on the lateral band. This can be reinforced with additional sutures to the surrounding periosteum and soft tissue. Any excess lateral band tissue proximally is then excised (Fig. 12-6). Skin closure is P.179 P.180 per the surgeon's preference, and a protective dorsal splint is applied to maintain the desired position of the finger.

FIGURE 12-6 Sequence of surgical steps for spiral oblique retinacular ligament reconstruction. (Images courtesy

of James P. Higgins, MD., copyright James P. Higgins, MD.)

Procedures to Correct DIP-Primary Flexible Swan-Neck Deformity Terminal Tendon Repair, DIP Arthrodesis, and/or Central Slip Tenotomy (Fowler Release) The classic example of a DIP-primary flexible swan-neck deformity comes from a mallet finger injury that has not healed after several months either because of neglect or failed healing with either splinting or pinning of the DIP joint. As the terminal extensor tendon insertion at the base of P3 continues to retract proximally from nonhealing, there is added extension force at the PIP joint. This combination leads to a flexion deformity at the DIP joint and an extension deformity at the PIP joint, especially if a patient has a tendency toward PIP hyperextension at baseline. If the process is caught before a fixed deformity develops, then soft-tissue procedures are an option. If the terminal tendon is in good enough condition after debridement that the surgeon can reattach it to the base of P3 without excessive tension at the DIP or PIP joint, then this is an option, with reattachment being done via suture anchors or bone tunnels. After this, the DIP joint is usually pinned in neutral extension for protection of the repair for 6 weeks. If repair is not an option, then a Fowler central slip tenotomy at the PIP joint is typically preferred, with or without a procedure to further correct the DIP flexion deformity such as temporary pinning or arthrodesis. Fowler described two different extensor tendon release procedures, one to correct swan-neck deformities and one to correct boutonniere deformities. For this reason, surgeons and other healthcare providers should be careful when discussing Fowler releases or tenotomies so as to avoid confusion between these two procedures. In the case of swan-neck deformities, Fowler described release of the central slip at its insertion on the base of P2. For this procedure, the central slip is isolated and gradually released from the dorsal base of P2 until the PIP hyperextension deformity is corrected. By releasing the central slip, there is less extension force exerted at the PIP joint so that more can be transferred to the DIP joint via the intrinsic mechanism, provided that there is some degree of soft-tissue connection between the distal lateral band confluence into the terminal tendon and the dorsal P3. For DIP fusion, I prefer to use a distally based dorsal incision at the DIP joint with the transverse portion dorsally over the DIP extension crease and radial and ulnar midaxial extensions. The skin and subcutaneous tissue are elevated as a full-thickness flap distally just above the extensor tendon and P3 periosteum. If more exposure of distal P2 is needed, this can be converted into a full H-shaped exposure by extending the midaxial incisions more proximally to also create a proximally based dorsal skin flap. The terminal extensor tendon is transected if present, and the distal P2 and proximal P3 articular cartilage and subchondral bone are removed until there is healthy cancellous bone at each surface. I prefer to use a rongeur for this and to create a cup-and-cone configuration where the proximal P3 base is shaped as a cup to accept the rounded distal P2. There are several bone fixation options available; I use a headless cannulated screw when possible. Appropriate sizes are typically in sets that are in a range between 2.0 mm and 3.0 mm. I hold one of the screws adjacent to the P3 and obtain fluoroscopic images to ensure as best as possible that the trailing screw threads will not violate the P3 significantly. I drill the guidewire into the P3 from proximal to distal and check A/P and lateral fluoroscopy for central placement and then advance through the skin of the fingertip distally. I then take the guidewire out and reverse it and insert it into the base of P3 again from proximal to distal so the blunt tip of the wire exits the fingertip. The DIP fusion site is then reduced and the guidewire is driven proximally across the DIP into the base of P2. Fluoroscopic images are again taken to ensure acceptable placement of the wire in P2 and appropriate planned DIP fusion position. At this point, I also check clinical fusion position by flexing the wrist to use finger extensor tenodesis to simulate active finger extension and then simulate active finger flexion by extending the wrist and applying manual pressure to the forearm finger flexors. Having confirmed good fusion position, a small incision is made at the exit point of the guidewire at the fingertip, and a hemostat is used to spread down around the guidewire to the tip of P3. Use of fluoroscopy is invaluable in deciding how deep to insert the screw; I typically aim to engage the isthmus of P2 proximally and to bury the head just below the tip of P3 distally without

significantly violating the palmar or dorsal cortex, which could jeopardize fixation and disrupt the germinal matrix of the nail. Using fluoroscopy, I make sure the leading tip of the guidewire is located in the isthmus of P2 where I'd like the leading tip of the screw to be after insertion and measure the screw length based on this, typically subtracting a few millimeters from the measured length to allow for compression and for burial of the trailing thread in the distal P3. Some headless cannulated screw systems use a cannulated drill at this point, and others simply use a countersink at the distal P3 or nothing. Finally, the screw is inserted over the guidewire while an assistant holds the DIP fusion site in P.181 reduction and compression (Fig. 12-7). Fusing the DIP joint may be enough to correct the PIP hyperextension if it is not severe and the patient was still able to actively initiate PIP flexion without assistance preoperatively. In these cases, we are trying to prevent worsening of the PIP hyperextension by fusing the DIP joint and typically protecting the PIP joint postoperatively. If the PIP hyperextension is more severe to the point where the patient is unable to actively initiate PIP flexion unassisted, then a secondary procedure is performed using any of the softtissue options for PIP-primary flexible swan-neck deformity mentioned earlier.

FIGURE 12-7 DIP arthrodesis in the setting of swan-neck deformity.

Procedures to Correct Fixed Swan-Neck Deformity Extensor Tenolysis, Joint Capsulectomies, and Soft-Tissue Reconstruction For patients who have fixed swan-neck deformities but well-maintained articular cartilage and skeletal structures about the involved joints, the first-line option is hand therapy with progressive splinting or casts to attempt to convert a fixed deformity to a flexible deformity. This is typically trialed for at least 4 to 6 months before abandoning efforts, unless there is a compelling reason to do so sooner. If these efforts fail and the patient still has significant functional limitations, a surgical option is to release the components that are causing the fixed deformity in order to obtain passively correctable joints. In these cases, the surgeon makes his or her standard dorsal approach to the finger and first performs an extensor tenolysis. If this is insufficient to correct the fixed deformity, then a dorsal PIP capsulectomy is performed. Since the lateral bands are scarred dorsal-centrally, it is acceptable to release between the lateral bands and the central extensor tendon in order to further release the extensor mechanism and to gain access to the PIP joint. Once this is complete, the surgeon can excise the dorsal-radial and dorsal-ulnar PIP capsule, keeping the central slip insertion and collateral ligaments intact. A Freer elevator or similar tool can be gently inserted into the PIP joint to lyse any adhesions there and to also bluntly release the palmar aspect of the PIP joint. A gentle manipulation in flexion is again performed on the PIP joint. If there is still insufficient release, the collateral ligaments are gradually released with gentle manipulation performed after each partial release until flexion is adequate. Once the fixed deformity has been made passively flexible, the surgeon may then perform one of the previously described soft-tissue reconstructions to maintain correction of the swan-neck deformity. Small Joint Arthroplasty and Arthrodesis For patients with fixed swan-neck deformity with poor articular cartilage or contractures that are too severe for releases and soft-tissue reconstructions, small joint arthroplasty and arthrodesis are the final surgical options short of amputation. These procedures are typically reserved for

patients with severe arthritic changes in the joints or severe contractures that involve the majority of the structures about the joints, that is, skin, subcutaneous tissue, tendons, ligaments, and joint capsule. Contractures such as these can occur following burns, severe crushing trauma, destructive infections, neuromuscular spasticity conditions, and in association with scleroderma, gout, or similar autoimmune inflammatory disorders. Unfortunately, small joint arthroplasty typically only maintains the same preoperative range of motion or may provide some marginal improvement. Thus, for fixed swanneck deformities of this type, the role of small joint arthroplasty is rather limited. Instead, most surgeons consider small joint arthrodesis for these situations as long as the skin and soft tissue envelope permit. For fixed swan-neck deformities that require PIP fusion due to articular damage or severe contracture, I prefer a tension band technique using 0.045 smooth K-wires for the longitudinal component and approximately 26-gauge stainless steel wire for the figure-of-eight configuration (Fig. 12-8). P.182

FIGURE 12-8 Pre- and intraoperative images of PIP arthrodesis for fixed swan-neck deformity.

POSTOPERATIVE MANAGEMENT FDS Tenodesis of the PIP Joint, Lateral Band Relocation, and SORL Reconstruction Patients are placed in a dorsal splint immediately postoperatively. If patient compliance is a concern, a dorsal blocking pin can be placed in the distal dorsal P1 at the articular margin to prevent PIP extension beyond a certain degree, typically approximately 30 degrees. At the first outpatient visit, a therapist makes a dorsal blocking splint for the PIP joint that allows flexion as the patient's pain and soft tissues permit. For the spiral oblique retinacular ligament (SORL) procedure, the DIP joint is included in the splint in neutral position and is protected in neutral during range-of-motion exercises. If a pin was used for the DIP joint or to block PIP joint extension, they are usually removed at 3 to 4 weeks postoperative. At 6 weeks postoperative, if the PIP joint is stable to gentle extension stressing, the dorsal block splint can be weaned off. At this point, once range of motion is adequate without any tendency toward deformity recurrence and there is minimal edema and pain, the therapist can begin progressive strengthening and return to functional activities for the patient.

Extensor Tenolysis, Joint Capsulectomies, and Soft-Tissue Reconstruction As long as there are no soft-tissue or bone/joint issues that need protection postoperatively, for these procedures, I allow immediate range of motion as tolerated by the patient. I use a long-acting local anesthetic for

the digital block at the end of the procedure to allow the patient to do ROM as tolerated. For this reason and for the early formal therapy sessions, I use Nylon sutures for the skin. Our therapists have communicated that doing so makes them more confident in pursuing aggressive range of motion in the early postoperative period with less fear of incision dehiscence. I then prefer to use a light gauze dressing for the finger followed by loosely applied Coban from the fingertip into the hand and locked at the wrist. The Coban is loosely laid on the finger without any stretching of the Coban during application in order to prevent arterial or venous ischemia. After applying the Coban, the finger can be gently compressed by the surgeon to mold the Coban without causing excessive constriction. This helps with immediate edema control and still allows for ROM, which should be confirmed after dressing application. I am not aware of any confirmed advantages to starting hand therapy any sooner than 3 to 5 days postoperatively, whereas doing so is definitely painful for the patient and therapist and can lead to bleeding and incision dehiscence. Therapy beyond this point typically progresses as the patient's pain and soft tissues allow, including splints as needed to prevent PIP hyperextension and to regain the flexion gained in the operating room. P.183

DIP Arthrodesis With or Without PIP Hyperextension Procedure At the first postoperative visit, patients are fitted with an OT-fashioned DIP neutral splint. Whether a secondary surgical procedure was required for PIP hyperextension or not, I typically splint in the same manner with an extension of the DIP neutral splint to include a dorsal block to the PIP joint at around 30 degrees of flexion. The patient is permitted and encouraged to flex the PIP joint in the splint and after 4 to 6 weeks can start extending the PIP joint approximately 10 degrees per week with the goal of reaching near neutral PIP extension as long as there is no tendency toward recurrent hyperextension. At 6 weeks post-op, if the DIP fusion is clinically and radiographically stable, the patient is allowed to wean out of the DIP splint and can start some tip-pinch activities and increase activities from there as tolerated.

COMPLICATIONS Of course, the typical possible complications of any surgery can be seen following these procedures such as infection, pain, stiffness, weakness, recurrence, and unpredictable final function and symptoms. A potential complication that is particular to surgical attempts to correct swan-neck deformity is inadvertently converting the finger to a boutonniere deformity. Again, most of the swanneck procedures lead to an intended flexion contracture of the PIP joint, and surgeons have traditionally thought that, from a functional standpoint, patients tolerate boutonniere finger deformities better than swan-neck positioning. The main concern here is the development of a progressive boutonniere deformity with dysfunctional PIP flexion and DIP hyperextension. The procedures that are most concerning for this development from a pathoanatomic standpoint are lateral band relocation and Fowler central slip tenotomy. If the lateral band release has to extend distally into the triangular ligament, then this could lead to progressive palmar translocation of the lateral bands as the PIP joint buttonholes between them. If the lateral bands are simply released and not relocated palmarly during the swan-neck procedure, this could theoretically lessen the chance of developing a boutonniere deformity. Fortunately, however, even if one of the lateral bands is tethered palmarly during the swan-neck procedure, this tethering should prevent further palmar translocation. This, along with leaving the other lateral band untethered, should help to prevent a progressive boutonniere. For the Fowler central slip tenotomy, the gradual and gentle release of the central slip along with keeping the triangular ligament intact aims to prevent subsequent boutonniere deformity (6).

RESULTS Smith and Amirfeyz have provided an excellent review of the latest results of procedures for flexible swanneck deformities (4). They noted that the authors of a recent retrospective review of patients undergoing FDS tenodesis with fixation at the A2 pulley level reported that 19 out of 23 of their patients had good or excellent results. Preoperative hyperextension averaged 33 degrees and patients gained 26 degrees of functional PIP flexion on average. For these patients, 70% had complete correction at the DIP level while 30% had at least some improvement and no worsening of the DIP flexion deformity (7). In the report on lateral band relocation by Tonkin et al., the authors reported on 12 patients with 30 flexible swan-neck deformities with multiple etiologies (8). The average preoperative PIP hyperextension deformity of 16 degrees corrected to an average flexion contracture of 11 degrees. Their average follow-up period was nearly 1 year postoperatively, and they reported no recurrences of the swan-neck deformity. deBruin et al. used the same technique for cerebral palsy patients and noted deterioration in the results after 5 years (9). This underscores the specialized issues of swanneck deformities in patients with neuromuscular conditions. Yet another modification of the lateral band relocation technique was recently described by Sirotakova et al. (1). In this case, the authors released the ulnar lateral band proximally, placed it through the flexor pulley, and tenodesed it at the P1, which is a combination of some of the techniques described earlier. They performed this procedure for 43 patients with 101 swan-neck deformities and at nearly 2 years of average postoperative follow-up noted an average correction of 13 degrees of PIP hyperextension to 13 degrees of flexion contracture and no recurrence of the deformity. The authors of another recent article reviewed their results of SORL lateral band transfer. At nearly 2 years of average follow-up, they reported no recurrences of swan-neck deformity. Average PIP hyperextension was improved from 21 degrees of hyperextension to 24 degrees of average flexion contracture. As with other procedures and reports, the overall range of motion was not significantly different postoperatively but was within a more functional range for patients (10). None of these more recent reports on technique modifications have any clinically significant differences from more historical results. This reinforces the concept that surgeons can likely perform any of the procedures that address the pathomechanics of the deformity and can expect reproducible results with little chance for recurrence in the typical patient population. P.184

REFERENCES 1. Sirotakova M, Figus A, Jarrett P, et al.: Correction of swan neck deformity in rheumatoid arthritis using a new lateral extensor band technique. J Hand Surg Eur 33(6): 712-716, 2008. 2. Engles D, Ditsios K, Boyer M: Reconstruction for flexible and fixed swan-neck deformities. In: Strickland J, Graham T, eds. Master techniques in orthopaedic surgery: the hand. 2nd ed. Baltimore, MD: Lippincott Williams & Wilkins, 2005: 435-447. 3. Curtis R: Sublimis tenodesis. In: Edmonson A, Crenshaw A, eds. Campbell's operative orthopaedics. 6th ed. St. Louis, CA: CV Mosby, 1980: 319. 4. Smith G, Amirfeyz R: The flexible swan neck deformity in rheumatoid arthritis. J Hand Surg [Am] 38(7): 1405-1407, 2013.

5. Feldon P, Terrono A, Nalebuff E, et al.: Rheumatoid arthritis and other connective tissue diseases. In: Wolfe S, Hotchkiss R, Pederson W, et al., eds. Green's operative hand surgery. 6th ed. Philadelphia, PA: Elsevier Churchill Livingstone, 2011: 2045. 6. Hiwatari R, Kuniyoshi K, Aoki M, et al.: Fractional Fowler tenotomy for chronic mallet finger: a cadaveric biomechanical study. J Hand Surg [Am] 37(11): 2263-2268, 2012. 7. Brulard C, Sauvage A, Mares O, et al.: Treatment of rheumatoid swan neck deformity by tenodesis of proximal interphalangeal joint with a half flexor digitorum superficialis tendon. Chir Main 31(3): 118-127, 2012. 8. Tonkin, M, Hughes J, Smith K. Lateral band translocation for swan-neck deformity. J Hand Surg [Am] 17(2): 260-267, 1992. 9. de Bruin M, van Vliet D, Smeulder M, et al.: Long-term results of lateral band translocation for the correction of swan neck deformity in cerebral palsy. J Pediatr Orthop 30(1): 67-70, 2010. 10. Borisch N, Haubmann P: Littler tenodesis for correction of swan neck deformity in rheumatoid arthritis. Oper Orthop Traumatol 23(3): 232-240, 2011.

Chapter 13 Correction of Posttraumatic Extensor Tendon Ulnar Subluxation of the Metacarpophalangeal Joint with a Dynamic Lumbrical Tendon Transfer Keith A. Segalman Beatrice L. Grasu E. F. Shaw Wilgis

INDICATIONS/CONTRAINDICATIONS Posttraumatic failure of the sagittal bands (SBs) at the level of the metacarpophalangeal (MCP) joint results in extensor tendon instability. When the extensor tendon is no longer centered over the MCP joint, there is a resultant loss of extension of the finger. Legoust first described traumatic extensor tendon instability in 1866. Paget, Krukenberg, and Marsh provided later descriptions of the condition. The technique described here has not been previously published.

PHYSICAL EXAMINATION The SB is the main stabilizer of the extensor digitorum tendon at the level of the metacarpal phalangeal joint. The SB forms a cylindrical tube surrounding the metacarpal head and the MCP joint (Fig. 13-1). The sagittal fibers are superficial to the MCP joint capsule, and there P.186 is no communication between the sagittal fibers and the collateral ligaments. The radial SB is thinner and longer than are the ulnar fibers. The SB is thicker in the central digits and thinner in the peripheral digits. The greatest tension in the SB is noted with MCP flexion and radioulnar deviation, with a vast majority of the injuries occurring on the radial side. Biomechanical studies have shown that greater than 50% of the proximal radial fibers must be torn to create extensor tendon instability (Fig. 13-2). The usual mechanism of injury is a blow to the hand with the MCPs flexed, such as a boxing injury. SB injuries occur when the finger is forced into flexion with the wrist flexed and ulnarly deviated. Rarely, P.187 an SB injury may be associated with collateral ligament injuries. The patient will usually present with swelling and tenderness over the SB and limited or deviated extension of the MCP joint. The most telltale finding is a painful snapping sensation with concomitant ulnar subluxation of the extensor tendon during active MCP flexion (Fig. 13-3). Rayan and Murray described a provocative test for SB injury: resisted finger extension and attempted deviation toward the injured SB elicit apprehension and pain.

FIGURE 13-1 Normal anatomy of the MCP joint (A) and the sagittal fibers (B).

FIGURE 13-2 Diagram of a sagittal band injury. (Adapted from Caroll C IV, Moore JR, Weiland AJ: Posttraumatic ulnar subluxation of the extensor tendons: a reconstructive technique. J Hand Surg Am 12: 227-231, 1987.)

FIGURE 13-3 Clinical photograph showing the subluxation of the extensor tendon. Two classification systems have been described, but in our opinion, neither fully characterizes the clinical situation. Ishizuki differentiates ruptures of the SB secondary to superficial tears and deep tears. Rayan and Murray have described a more treatment-oriented classification system of three P.188 varieties emphasizing whether the SB is torn or there is subluxation of the tendon. What is most important is the assessment of the passive motion in the joint and the stability of the contralateral ligaments. For acute injuries, immobilization with a cast or Orthoplast splint with the MCP joints in extension and the wrist in neutral is often satisfactory. Rayan and Murray have reported that conservative treatment is most successful when begun within 3 weeks of the injury, whereas Inoue recommended repair or reconstruction when the patient is seen more than 2 weeks after the injury. Occasionally, conservative treatment of acute injuries is unsuccessful, but most patients with SB injuries will present with a chronic condition. Extensor tendon instability is most common in the middle finger, followed by the small, index, and ring fingers. Various authors have suggested that the middle finger is most often involved because of the cross-sectional thickness of the SB, the distal attachment of the extensor hood, or the increased proximal-distal length of the SB. These authors noted a less well-developed juncture tendinum in the radial two digits and excessive ulnar deviation of the metacarpal head in the middle finger versus the ulnar two digits. In our experience, the middle finger is most often involved.

PREOPERATIVE PLANNING It is imperative to ensure that there is full passive motion in the digit. Radiographs should be obtained to confirm that there is no underlying fracture or arthritis. There is no role for arthrography or arthroscopy in the treatment of this condition. The lumbrical muscle is chosen for reconstruction given its radial location, ease of harvest, and, most importantly, its synergistic action to stabilize and radialize the extensor tendon. The lumbrical muscle inserts in the transverse or oblique fibers of the extensor, with half of the fingers having an additional attachment to tendon or bone (Fig. 13-4). The lumbrical has no role in MCP flexion, P.189 whereas the interossei are the main flexors of the proximal phalanx. Electromyographic studies have determined that the lumbrical fires with digital flexion to prevent clawing. Since extensor instability is most pronounced with MCP flexion, transferring the lumbrical will serve as a direct antagonist to the deforming force of the extensor.

Thus, the lumbrical acts as a dynamic tendon transfer to correct ulnar subluxation of the extensor tendon.

FIGURE 13-4 Normal anatomy of the lumbrical muscle.

SURGERY Local anesthesia with sedation is the preferred choice, but regional anesthesia is an acceptable alternative. The patient is positioned supine on the operating room table. An upper arm tourniquet is applied, and the arm is draped in a standard fashion. After exsanguination of the arm, a dorsal 4-cm incision is centered over the MCP joint (Fig. 13-5). The pathology is confirmed, and the extensor is reduced over the MCP joint. Reduction of the extensor typically does not require release of the ulnar sagittal fibers. The lumbrical is harvested just proximal to its insertion into the oblique fibers and gently mobilized proximally (Fig. 13-6). Care is taken to avoid detaching the tendon from the muscle belly and P.190 separating the lumbrical from the interossei. Because the lumbrical and interossei join into one conjoined tendon, the lumbrical could easily be separated from the muscle belly if the surgeon is not careful.

FIGURE 13-5 Dorsal incision over the MP joint demonstrating ulnar subluxation of the extensor and attenuation of the radial sagittal fibers.

FIGURE 13-6 Harvesting the lumbrical from just proximal to its tendinous insertion.

FIGURE 13-7 Passage of the tendon transfer through a split in the extensor dorsally. An isometric point is chosen for passage of the transfer by holding the extensor reduced with a pair of forceps and gently ranging the finger or asking the patient to gently flex the finger. The tendon of the lumbrical is now passed through a small longitudinal slit in the extensor at the isometric point (Fig. 13-7). The tension is set by ranging the finger and ensuring that the extensor does not subluxate ulnarly. If the ulnar sagittal fibers were released and excess tension was applied to the transfer, then radial subluxation would result. A nonabsorbable 4-0 suture is used to secure the transfer. The wound is closed with nonabsorbable sutures, and the patient is immobilized in a short splint with the MCP joints in extension and the proximal interphalangeal joints free.

POSTOPERATIVE MANAGEMENT The sutures are removed 8 to 10 days after the surgery, and immobilization is continued for a total of 4 weeks after surgery. We prefer a short arm cast with the wrist in neutral and the MCP joints in extension. It is important to leave the proximal interphalangeal joints free. Dynamic extensor splinting is not usually used, but it is a reasonable alternative. The patient is expected to regain nearly full motion and strength. Active motion is begun 4 weeks after surgery, and strengthening is begun 6 weeks after surgery. The patient will continue with therapy for approximately 6 to 8 weeks (Fig. 13-8). Minimal loss of motion is expected from this technique. The patient should be able to return to normal activities within 3 months. In our experience, there has never been a recurrence. P.191

FIGURE 13-8 Intraoperative photograph (A) and postoperative photographs after lumbrical transfer for extensor tendon instability. Postoperative dorsal view (B), active extension (C), and active flexion and centralization of the tendon (D) are shown.

RESULTS Stiffness is rarely a problem after the procedure, as the joint capsule is not violated. In our experience, patients have averaged 90 degrees of MCP motion. We have not seen any recurrence of the deformity, and all patients have been satisfied with the procedure. No interphalangeal stiffness has been identified.

COMPLICATIONS The complication rate is very low. Superficial infection has only occurred in one patient, and this was successfully treated with oral antibiotics without the need for further surgery. No deep infection has been identified, and we feel that there is no indication to routinely use preoperative antibiotics. P.192 As noted above, the surgeon should expect minimal stiffness after the surgery. Radial deviation has not been seen and would not occur with normal bony architecture. There has not been any need for secondary surgery, and all patients were satisfied with the procedure. In theory, a failure could result in recurrent subluxation after removal of the cast. If recurrence occurred, we would prefer the technique described by Carroll et al.

CONCLUSIONS A lumbrical muscle transfer provides excellent correction for SB ruptures of the extensor located over the MCP joint. The lumbrical is a dynamic transfer easily harvested, which minimizes stiffness. Complications are few, and recurrence has not been observed in our series of patients.

RECOMMENDED READING Carroll C, Moore JR, Weiland AJ: Posttraumatic ulnar subluxation of the extensor tendons: a reconstructive technique. J Hand Surg Am 12: 227-231, 1987. ElMaraghy AW, Pennings A: Metacarpophalangeal joint extensor tendon subluxation: a reconstructive stabilization technique. J Hand Surg Am 38: 578-582, 2013. Inoue G, Tamura Y: Dislocation of the extensor tendons over the metacarpophalangeal joints. J Hand Surg Am 21: 464-469, 1996. Murray D, Rayan GM: Late reconstruction of sagittal band laceration. Orthop Rev 23: 445-447, 1994. Rayan GM, Murray D: Classification and treatment of closed sagittal band injuries. J Hand Surg Am 19: 590594, 1994. Ritts GD, Wood MB, Engber WD: Nonoperative treatment of traumatic dislocations of the extensor digitorum tendons in patients without rheumatoid disorders. J Hand Surg Am 10: 714-716, 1985. Saldana MJ, McGuire RA: Chronic painful subluxation of the metacarpal phalangeal joint extensor tendons. J Hand Surg Am 11: 420-423, 1986. Smith RJ: Intrinsic muscles of the fingers: function, dysfunction, and surgical reconstruction. In: AAOS instructional course lectures. Vol. 24. St. Louis, CA: Mosby, 200-220, 1975. Watson HK, Weinzweig J, Guidera PM: Sagittal band reconstruction. J Hand Surg Am 22: 452-456, 1997.

Chapter 14 Zone 1 Flexor Tendon Injuries Blaine Todd Bafus Eugene Y. Tsai Catherine Szado

OVERVIEW Acute zone I flexor tendon injuries are a commonly encountered condition caused by either an avulsion of the flexor digitorum profundus (FDP) tendon from its insertion on the distal phalanx of the finger (the so-called jersey finger) or a laceration of the FDP tendon distal to the insertion of the flexor digitorum superficialis (FDS) tendon. A frequently used classification system for these types of injuries was introduced by Leddy and Packer (1) in 1977 with a modification added by Trumble et al. (2) in 1992. This classification system aids the surgeon in choosing timing of and appropriate treatment for these injuries. Type I injuries occur when the FDP tendon avulses and retracts into the palm, thus disrupting the entire blood supply and nutritional support of the tendon. The viability of the tendon is jeopardized, and repair must occur within 7 to 10 days of injury. Type II injuries occur when the tendon retracts to the level of the proximal interphalangeal (PIP) joint, which likely signifies some remaining blood supply via the long vinculum and diffusion of nutrients through the synovial fluid. Delayed repair up to 6 weeks postinjury can be attempted with success (however, the goal should be repair as soon as possible). Type III injuries occur when the tendon only retracts to the level of the A4 pulley typically because the FDP tendon avulses a piece of bone, which prevents further retraction. Both vinculae remain intact and tendon viability is preserved affording delayed repair. Type IV injuries occur when the FDP tendon detaches and retracts from the bony avulsion fragment and viability of the tendon is unpredictable. Differentiating between type III and IV injuries can be challenging, and when physical exam findings are inconclusive, further imaging may be required. While all of these injuries occur outside of the proverbial “no man's land,” they still pose significant challenges, which include localizing the tendon and passing it through the annular pulleys of the retinacular sheath, achieving robust healing between tendon and bone, as well as avoiding the “quadrigia” effect, which can occur when the tendon is shortened greater than 1 cm. This shortening places increased tension on the remaining tendons of the FDP muscle with resultant diminished flexion of the remaining digits or “quadrigia.” We will limit our discussion in this chapter to the repair of acute zone I tendon injuries.

CLINICAL PRESENTATION Patients classically present with a history of a forced extension injury to an actively flexed digit or a laceration sustained to the volar surface of the digit distal to the insertion of FDS. On physical exam, the normal cascade of the fingers will be disrupted with the affected finger held in a more extended posture. The patient will be unable to actively flex the distal interphalangeal (DIP) joint, most easily tested by holding the metacarpophalangeal (MCP) and PIP joints of the digit in full extension. Sometimes, an avulsed bony fragment may be palpated along the digit. A thorough examination of the entire hand and forearm should be performed to identify any other concomitant injuries. The point of maximum tenderness along the injured digit or proximally in the palm is often an indication of where the proximal avulsed tendon end resides. Radiographs may demonstrate the location of an avulsed bony fragment or any other bony injury. When the diagnosis remains elusive, ultrasound P.194 (US) or magnetic resonance imaging (MRI) may be appropriate. These additional imaging modalities can also aid in identifying the location of the proximal FDP tendon stump, which in a delayed presentation may alter the treatment course.

The restoration of function to a digit that has sustained a flexor tendon injury can be a long and tedious road. Considerable time should be devoted to counseling the patient regarding the nature of the injury as well as the possible need for secondary operations and the extensive postoperative rehabilitation required to achieve a desirable outcome.

INDICATIONS Most zone 1 tendon injuries should be considered for prompt surgical repair unless prohibited by medical or social factors. The above mentioned classification system is helpful in determining the timing of intervention and appropriate care. Delayed presentation of type I and II injuries is oftentimes better managed with nonoperative care or DIP joint arthrodesis. Two-stage tendon reconstruction of zone I injuries requires passing a tendon graft through an intact FDS insertion with potential adhesions and suboptimal functional results. Patients presenting with suspected type III/IV injuries in a delayed fashion must also be counseled that intraoperative findings of more proximal tendon retraction either secondary to tendon avulsion off the bony fragment or inaccurate initial diagnosis may preclude primary repair.

CONTRAINDICATIONS Active infection Wound contamination Significant skin loss over the flexor tendon Multiple severe injuries to the hand and fingers For some patients, a primary DIP fusion may be a reasonable alternative.

PREOPERATIVE PREPARATION As stated above, a thorough physical examination will most oftentimes determine the extent of injury. The surgeon must note the normal resting finger cascade, location, and extent of any wounds; document individual tendon function of the FDS and FDP; and assess digital nerve function and vascular integrity of the digit. We also carefully palpate along the flexor sheath and palm evaluating for the point of maximum tenderness. This point most often corresponds with the location of the retracted tendon end. Radiographic examination of digit and hand evaluates for avulsion fractures of distal phalanx volar rim and associated bony injuries. More advanced imaging (MRI/US) is utilized at the surgeon's discretion and is individualized by each case and unique presentation.

TECHNIQUE Either regional or general anesthesia is utilized per surgeon and anesthesiologist choice. Wide awake surgery is gaining popularity for these injuries but has yet to be utilized at our institution and is discussed in detail elsewhere in this book. The patient is placed supine on the operating table with the arm abducted 90 degrees at the shoulder and a well-padded tourniquet is applied. Preoperative antibiotics are administered within 1 hour of skin incision. The surgical “time-out” is completed. The “time-out” is an opportunity to confirm that all special equipment is available including tendon graspers, pediatric feeding tube, handheld power/wire driver, micro instruments, and fracture fixation set when indicated and sheath dilator (we routinely use the Toby Orthopaedic disposable device). The suture of choice is individualized, but we prefer for an end-to-end repair to use 4-0 looped Supramid Extra LCW on a 3/8 inch taper needle or 4-0 Ethibond suture on an RB1 taper needle. For a tendon to bone repair, we use a 3-0 Ethibond suture and two Keith needles. Alternatively, micro-sized suture

anchors of choice may be utilized. The arm is exsanguinated, and the tourniquet is inflated to 100 mm Hg above the patient's systolic blood pressure. The surgical approach can vary between a Brunner style and midaxial incision along the digit with extension proximally into the palm as needed. Generally, we prefer an oblique incision over the distal phalanx with a midaxial extension toward the MP flexion crease if a proximal extension is anticipated (Fig. 14-1). The incision should be favored to the side of a concomitant digital nerve injury when present. T-shaped extensions of transverse lacerations should be avoided but may be dictated by the situation. A window in the flexor sheath may be required for repairs between A2 and A4. We have P.195 released part of or all of the A4 pulley to accommodate the repair without any noted complications. Alternatively, if the DIP joint was flexed at the time of injury, the distal stump may be accessed by opening the C3-A5 complex. Tendon retrieval can be difficult, and proper technique at this stage will impact overall outcome. The extent of proximal retraction determines the technique utilized. When the tendon end is visible, it may be retrieved by gently grasping with a tendon grasper or hooked with a single prong skin hook. Repeated blind grasps into the flexor sheath should be avoided. Alternatively, some have had success milking the tendon from proximal to distal. For a tendon that has withdrawn proximally into the sheath or palm, a proximal midpalmar incision may be used as a window to obtain the tendon (Fig. 14-2). If it is still within the sheath, a retrograde feeding catheter (#5 pediatric feeding tube) may be passed retrograde down the flexor sheath and sutured to the tendon proximal to the A1 pulley. This will preserve the FDP and FDS relationship within the chiasm. The catheter is then pulled distally, which easily delivers the tendon stump into the distal repair site. A transversely oriented 25-gauge needle then secures the tendon for repair, and the connecting suture is severed within the palm and the catheter is withdrawn. Similarly, the FDP tendon that has withdrawn completely into the palm may have a suture placed within the stump and be drawn distally using a tendon grasper. End-to-end tendon repair requires a distal tendon stump of sufficient length—at least 0.75 cm. We prefer a locked cruciate 8 strand repair utilizing the looped Supramid suture (Fig. 14-3). We supplement our repair with a volar epitendinous stitch using a running locking 6-0 nylon suture. Direct tendon to bone repair is the more common scenario (Fig. 14-4). A 3-0 Ethibond suture is placed into the tendon stump utilizing a Bunnell style technique crossing 3 times and coming out distally. The insertion site is freshened up to bone with a small rongeur. There is no need to create a bone trough on the volar cortex. Keith needles are advanced through the distal phalanx at the FDP insertion site from volar to dorsal, exiting proximal to the germinal matrix (Fig. 14-4A). We utilize a wire driver to place our Keith needles and confirm position with intraoperative imaging. A small nick in the dorsal skin is made, and the sutures are tied over the bone and extensor tendon (Fig. 14-4B, C). Digital nerve and vessel repairs are performed at this time when indicated.

FIGURE 14-1 An oblique incision is made over the distal phalanx.

FIGURE 14-2 A proximal midpalmar incision may be used to obtain the FDP tendon. P.196

FIGURE 14-3 Locked cruciate suture technique. (From Berger RA, Weiss A-PC: Hand surgery. Philadelphia, PA: Lippincott Williams & Wilkins, 2003.)

FIGURE 14-4 A-C: Two Keith needles are advanced through the distal phalanx from volar to dorsal proximal to the germinal matrix. Prior to skin closure, repair integrity and appropriate tendon gliding are confirmed. I prefer to let down the tourniquet at this time and achieve meticulous hemostasis. Diminishing postoperative hematoma, swelling, and pain encourage and enhance our early motion therapy protocol. Skin closure is at surgeon's discretion. A wellpadded dorsal blocking splint is applied with the wrist in 20 degrees of flexion, MP joints flexed, and IP joint extended. We include all digits (excluding the thumb) in our dressing. Instructions pertaining to strict elevation and the importance of maintaining the postoperative dressing are stressed prior to patient discharge.

PEARLS AND PITFALLS The proper relationship of the FDP and FDS must be re-established. The FDP passes through the slips of the FDS and palmar to Camper's chiasm. The FDP should not be advanced more than 1 cm, or “quadregia” may result. Repair the tendons prior to any microsurgical procedures. The Toby instrumentation is helpful for passing an edematous tendon through a pulley. Avulsion fragments too small to accept a screw are excised and the tendon repaired to the distal phalanx as outlined. Take care to not bring the Keith needles up through the germinal matrix. The knot may become symptomatic after the tendon has healed requiring removal. This can be done using a scalpel and digital block in clinic at least 6 weeks after tendon repair. The all-inside technique avoids the complications associated with an external button and the costs associated with suture anchors. P.197

POSTOPERATIVE MANAGEMENT The challenging goal is for tendons to heal without rupture or gap and to glide freely with minimum adherence to the surrounding structures, thus maximizing functional outcomes. At our institution, we have adapted components of the Duran, Kleinert, and Indiana Tenodesis programs. We also incorporate the “Pyramid of progressive force exercises” as outlined by Groth (3). Key components include controlled passive range of motion (PROM) and gentle active flexion combined with synergistic wrist extension. Each therapy program is individualized and considers adhesion formation, edema, severity of injury, delay in repair, and quality/type of repair. Additionally, the patient's medical comorbidities, smoking and substance abuse, and socioeconomic factors will all influence the rehabilitation protocol. Phase 1 (3 days to 3 weeks postoperative): The patient is educated on compliance, signs of infection, precautions, edema control, and scar massage. Splint: custom dorsal blocking splint with the wrist in neutral, MCPs at 50 to 60 degrees, and IPs in full extension. We typically do not add more flexion for concomitant digital nerve repairs. If patient compliance is a concern, the operative dressing may initially be debulked, and the patient begins a controlled mobilization program with the operative splint intact. This allows the therapist time to establish a rapport with the patient. Careful monitoring of PIP and DIP flexion contractures is vital. Rubber band traction: despite the decreased popularity of Kleinert's dynamic traction program, we have found that in certain patients, this program promotes compliance. To prevent PIP flexion contractures, rubber bands are removed at night and a Velcro strap is applied to hold the PIP joints in extension. Exercises: with splint on, modified Duran exercises are initiated including isolated passive DIP motion and isolated PIP motion. Passive composite finger extension with MCP flexion is also incorporated. For compliant patients with a strong repair, active place and hold exercises are initiated on the first postoperative visit after warming up with the modified Duran passive exercises. We also start tenodesis exercises at this time. The splint is removed for active place and hold exercises, which allows for the wrist to extend 20 to 30 degrees. If the patient is noncompliant, place and hold exercises and tenodesis exercises

are done only in therapy. Frequency and vigor of exercises depends on edema, stiffness, pain, and adhesion formation. If adhesions are significantly limiting tendon gliding, treatment is progressed in accordance with the previously mentioned pyramid of progression. Conversely, if the tendon is gliding freely, the patient is protected longer. Phase 2 (3 to 6 weeks postoperative): Splint: begin weaning out of the splint, which may include modifying to a hand-based splint, buddy tape for protection, and PIP extension splinting if indicated. Precautions: non-weight bearing with fingers and wrist extended. No forceful grasping. Use of hand for light ADLs only. Exercises: evaluate for adhesions and active flexor lag. Begin active place and hold and tenodesis exercises if not previously started. Initiate tendon glides (active composite fist, hook, straight fist, and isolated FDS gliding). Blocking exercises to the DIP and PIP are initiated with careful instruction not to overly strain against the blocking mechanism. Blocking exercises to the DIP and PIP are started toward the end of phase 2; however, early blocking exercises are not initiated in FDP repairs of the small finger. Phase 3 (6 to 12 weeks postoperative): Monitor for adhesion and active flexor lag, advance as appropriate. Progress to light strengthening with putty and sponge. Resisted tendon gliding and blocking are not started until 8 weeks postoperatively. Return to work/unrestricted ADLs averages 10 to 12 weeks postoperatively. Pearls and Pitfalls: The postoperative program must be individualized and requires an experienced hand therapist. If adhesions and joint stiffness are limiting tendon gliding, treatment is progressed. Conversely, if the tendon is gliding freely, the patient is protected longer. Communication between the therapist and surgeon is critical. Patient compliance and motivation will greatly influence functional outcomes.

COMPLICATIONS Rupture of a flexor tendon repair is a significant complication. It may occur during therapy, with inadvertent strong gripping or lifting, or while the patient is sleeping. Using modern techniques, good early range of motion may breed overconfidence in the strength of the healing tendon. P.198 Once a rupture is suspected, the preferred treatment is prompt exploration and repair. In the case of a zone 1 rerupture, the patient may opt for a DIP fusion rather than a staged reconstruction if the tendon is no longer directly repairable. The most frequent late complication following early postoperative mobilization programs is the development of flexion contractures at the PIP or DIP joints or both. Prompt recognition of the development of contractures, modification of the motion program to permit greater extension, and the judicious use of dynamic splints can help to prevent or overcome these deformities before they progress too far. Alternatively, tendon adhesions may form and prohibit sufficient gliding of the tendon to allow for adequate

digital function. After several months, if no appreciable improvement in motion despite vigorous therapy occurs, a tenolysis procedure may be considered. This should only be performed after the tissues have reached “equilibrium” with soft pliable skin and subcutaneous tissues and minimal reaction around the scars. Joint contractures must be mobilized and a normal or near-normal PROM achieved prior to considering tenolysis.

RESULTS We have been using the all-inside zone 1 repair at our busy urban trauma center for several years. A recent attempt to perform a retrospective analysis on the clinical results of the technique at our institution was stifled by the unexpectedly poor follow-up of this injury in our population. Anecdotally, this technique in our hands has not been associated with an increased rate of failure over the button technique and avoids the risks associated with an external device in our population (Fig. 14-5). The technique was recently evaluated in a cadaveric study by Chu et al. (4) and found to be comparable to the other available surgical repairs.

FIGURE 14-5 A-C: Clinical photographs following repair of a zone I flexor tendon injury.

P.199

ACKNOWLEDGMENT The authors would like to thank Dr. Kevin Malone for the use of his clinical images.

REFERENCES 1. Leddy JP, Packer JW: Avulsion of the profundus tendon insertion in athletes. J Hand Surg [Am] 2: 66-69, 1977.

2. Trumble TE, Vedder TE, Benirschke SK: Misleading fractures after profundus tendon avulsions: a report of 6 cases. J Hand Surg [Am] 17: 902-906, 1992. 3. Groth GN: Pyramid of progressive force exercises following flexor tendon repair. J Hand Ther 17: 31-42, 2004. 4. Chu J, Chen T, Awad H, et al.: Comparison of an all-inside suture technique with traditional pull-out suture and suture anchor repair techniques for flexor digitorum profundus attachment to bone. J Hand Surg [Am] 38A: 1084-1090, 2013.

Chapter 15 Zone II Flexor Tendon Repair David B. Shapiro Nathan A. Monaco In flexor tendon parlance, the region between the distal palmar crease and the FDS insertion has been described in many ways, from Bunnell's initial description as “no man's land” (1) to McCash's more descriptive “deathbed of many a stout profundus” (2,3) to Verdan's present-day “zone II” (4) (Fig. 15-1). It is the area where the flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) change position relative to one another within the confines of the fibroosseous digital sheath. Based on previous attempts at repair, Bunnell stated that tendons lacerated at this level “cannot [be joined] by suture with success… It is better to remove the tendons from the finger and graft in a new tendon” (1). Although some advocated primary repair as early as 1940 (including Bunnell, in certain circumstances), a long tradition of excision and grafting limited enthusiasm for tendon repair (6). Verdan's promising early results (7) began to usher in a new era in tendon repair. Kleinert et al. (8) presented their 10-year experience in zone II tendon repairs, rehabilitated with an early, protected motion program, set the stage for the progressive advances in tendon repair that followed. Advancements in our knowledge of tendon biology and suture characteristics, the routine use of loupe magnification, more refined operative repair techniques, and better postoperative rehabilitation protocols have led to the establishment of primary tendon repair as the current standard of care for zone II flexor tendon lacerations (9). At present, the goals of flexor tendon repair include precise approximation of the tendon ends to promote intrinsic tendon healing, creation of a repair site with sufficient strength to limit gap development during the entire recovery process, and development and execution of a rehabilitation protocol to limit tendon adhesion and maximize digital motion without causing rupture of the repaired tendon. Obtaining consistent, excellent results in these injuries remains challenging for surgeons, patients, and therapists alike.

ANATOMY Digital flexion is provided by two tendinous extensions of the extrinsic forearm muscles, the FDS and FDP. The flexor pollicis longus tendon provides extrinsic thumb flexion. The FDP has one common muscle belly (often with a separate radial bundle directed toward the index finger) originating on the anterior-medial ulna and interosseous membrane, which sends individual tendons to insert on the distal phalanx of each finger. Lumbrical muscles originate from the four FDP tendons in the palm, with their own tendons joining the interosseous tendon and forming the radial lateral band. The FDS originates from multiple points on the distal humerus, ulna, and radius. In the midforearm, it divides into four distinct muscle bellies, with a superficial layer to the long and ring fingers, and a deeper layer to the index and small fingers. The FDS tendons lie superficial to the FDP in the palm, dividing, rotating, and inserting over the proximal third of the middle phalanx, with interconnections between the two FDS slips at Camper's chiasm, over the PIP joint (10) (Fig. 15-2). While independent FDS function to the small finger is often absent, the tendon itself is almost always present (12). The fibrous retinacular sheath, or pulley system, consists of five annular and three cruciate condensations (also shown in Fig. 15-2). The sheath begins at the metacarpal neck and ends at the distal phalanx, although tenosynovial extensions to the wrist occur in the thumb and small finger (the radial and ulnar bursae). The sheath and synovial system function to maintain a P.202 smooth gliding system for the tendons, to provide nutrition and lubrication, and, at the level of the pulleys, to

keep the tendons close to the axis of joint rotation, increasing mechanical efficiency and preventing bowstringing. Intrinsic blood supply to the flexor tendons occurs through the vincula (Fig. 15-3), with relatively avascular areas beneath the A2 and A4 pulleys.

FIGURE 15-1 Flexor tendon zones I through V. Zone I is distal to the FDS insertion, zone II between the FDS insertion and beginning of A1, zone III in the palm, zone IV under the transverse carpal ligament, and zone V proximal (Verdan C: Primary repair of flexor tendons. J Bone Joint Surg Am 42(A): 647-657, 1960, Ref. 5).

FIGURE 15-2 Flexor tendon pulley system. The annular pulleys are designated A1 through A5, with cruciate pulleys C1, C2, and C3. This specimen has a relatively thin A4. Tang's subdivision of Zone II includes 2A which covers the long insertion of the FDS; 2B extending from the proximal edge of 2A to the distal edge of the A2 pulley; 2C covering the length of the A2 pulley; and 2D which is proximal to A2. (Tang JB. Flexor tendon repair in zone 2C. J Hand Surg Br 19(1): 72-75, 1994.) The actual repair can traverse more than one subdivision as the digit moves. Note how the FDS tightly encircles the FDP (held in the retractor) beneath and distal to the A2 pulley. Kleinert and Verdan described five flexor tendon zones on the palmar aspect of the hand, based on anatomic differences and healing potential (Fig. 15-1) (4,5). Zone II spans from the proximal aspect of the A1 pulley to the insertion of the FDS on the middle phalanx and can be further divided into subzone A through D (11) (Fig. 15-2). P.203

FIGURE 15-3 Vincula—Note the location of the vincula, which provide a vascular supply to the tendons to aid in intrinsic tendon healing. The FDS tendon divides to allow the FDP to pass through, with tendinous interconnections at Camper's chiasm. VB, vincula brevis; VL, vincula longus; CC, Camper's chiasm.

INDICATIONS With rare exception, complete zone II flexor tendon lacerations require surgical intervention. It is important to ascertain when the injury occurred, the mechanism, and (if possible) the position of the hand at the time of injury. Saw injuries, or those with a crushing component, for example, can cause tearing of tendon edges, leading to different challenges in repair and rehabilitation when compared to the clean tendon transections seen after sharp knife lacerations (13). Injuries that occur when the hand is closed will result in tendon lacerations well distal to the skin laceration. When examining the patient, make note of the location and degree of wound contamination to aid in planning incision extensions and to determine whether delaying repair will risk deep infection. Neurovascular examination should be performed to assess the integrity of the digital nerves. If both nerves are believed to be transected, more urgent exploration may be warranted if arterial repair is anticipated. The tendon laceration will often lead to an alteration of the normal resting digital cascade (Fig. 15-6A). Deep flexor tendon function is assessed by testing active flexion of the DIP joints. FDS function is tested by examining independent PIP flexion while the other digits are held extended (Fig. 15-4). X-rays are warranted to rule out any fractures or foreign bodies. Emergent primary repair of complete zone II flexor tendon injuries is necessary only in cases with gross contamination or vascular injury requiring repair. Isolated tendon repairs are technically easier to do sooner rather than later, but a 1-week (or even 2-week) delay seldom changes the difficulty or outcome. While surgical repair should be performed expediently, it is appropriate to delay until there is a full, well-rested surgical staff, appropriate assistance, and time to do a meticulous repair of all the injured structures. As time passes, edema of the tendon ends, muscle shortening, and scar in the sheath make tendon approximation and passage of the tendon under the pulleys more difficult.

FIGURE 15-4 A: Testing of the FDP is done by asking the patient to demonstrate active DIP flexion while the examiner holds the PIP extended and allows flexion of the other fingers. B: Testing of FDS by holding the others digits extended at the PIP and DIP joints and asking the patient to flex the injured digit. P.204 The most important step in preoperative preparation is a frank discussion with the patient regarding the implications of the injury, the anticipated outcomes, the importance of compliance in the therapy programs, and the required activity restriction. The patient should understand that unrestricted activity will need to be avoided for 3 months following surgical repair, that few patients will regain perfect motion, and that a few will require reoperation for rupture of the repair or stiffness.

CONTRAINDICATIONS Active infection and gross wound contamination: These may require debridement and a short delay in primary tendon repair. Delayed presentation: Presentation after a couple weeks will likely make primary repair more difficult. Exploration is still warranted, with primary repair of at least the FDP if possible (partial or total FDS excision may be required to pass the FDP through the pulleys). The surgeon must be prepared for an alternative procedure if primary repair without undue tension cannot be performed—either tendon grafting or placement of a silicone tendon rod as the beginning of a two-stage tendon reconstruction. Delayed presentation of an FDP laceration with intact FDS and good active PIP motion: Repair in this case risks damaging a functioning FDS in a case where, after exploration, primary repair may still not be possible. Tendon grafting or silicone rod placement should generally not be performed. A tenodesis of the FDP stump into the middle phalanx or A4 pulley can be performed in patients with passive DIP hyperextension.

OPERATIVE TECHNIQUE In this series, clinical and cadaver lab images are used to illustrate the points in the text. The patient is brought to the operating room after the administration of a prophylactic antibiotic. Regional anesthesia combined with intravenous sedation or general anesthesia is preferred, as involuntary, uncontrolled flexion of the fingers at the completion of the procedure will be prevented by the block. The arm is prepped and draped in a standard fashion, with the sterile field extending above the elbow. With the patient in the supine position and the surgeon seated in the axilla, the arm is exsanguinated and an upper arm tourniquet inflated to 100 mm Hg of mercury above systolic pressure (less for small arms). The initial laceration can be explored but will almost always require extension proximally and distally, with incisions either obliquely or along the midlateral line (Figs. 15-5 and 15-6B).

FIGURE 15-5 The traumatic laceration (red) will almost always need extension, by zigzag incisions (blue), midlateral extensions (yellow), or a combination. Midlateral incisions keep scar off the tendon repair and provide better proximal and distal access for any nerve lacerations. Zigzag flaps offer better exposure of the tendon. Keep flaps full thickness to prevent ischemia at the incision apices, identifying and protecting the neurovascular bundles. P.205

FIGURE 15-6 Surgery. A: Resting digital cascade after laceration of both tendons. B: Zigzag incision extension, with mark for possible palmar incision. C: Tendon ends distal to laceration. 1. FDP; 2. FDS; 3. laceration in volar plate; 4. distal edge of A2 with empty sheath. D: Becker repair in a slip of the FDS in zone IIB: Note that the suture knot is left outside of the repair in this small tendon, distal and to the side away from the FDP repair. A 4-0 or 5-0 Prolene is used and will easily slide to aid in tendon approximation. E,F: Initial and final stages of “backside-first” epitendinous repair. P.206

FIGURE 15-6 (Continued ) G: The core suture is being placed, and the loops are left long on the left side of the tendon. Once tightened, the repair will not slide. H: The core suture has been tied. I: Completion of the epitendinous repair. J: Normal resting posture. K: Dressings applied. P.207 Midlateral incisions leave less scar over the tendons, but zigzag incisions may provide better exposure. Skin flaps are raised, identifying and protecting both neurovascular bundles. If nerve repair is required, the nerve and vessel are dissected free to allow for neurorrhaphy after the tendon repair. The laceration in the tendon sheath is identified. The sheath can be opened along either side, proximal to A2 (A1 can be divided if necessary), between A2 and A4 (dividing A3 and the cruciate pulleys), or distal to A4, depending on the location of the injury. The tendon ends are seldom seen near the sheath opening. If the finger was flexed at the time of the injury, the distal ends will be well distal to the zone of injury when the digit is extended (Fig. 15-6C). The proximal ends may retract several centimeters, although FDP retraction is partially limited by the lumbrical attachments. Tendon retrieval distally can be done by flexing the digit. If less than a centimeter of the FDP tendons is

exposed, either open (“vent”) or remove the proximal half of A4. While it may be possible to withdraw the tendon distal to A4, place a suture, and pass the tendon back beneath the pulley, this limits the suture technique options and makes the epitendinous suture more difficult. Venting or even complete release of A4 is preferred to a weak repair or one that will not pass under the pulley (14). Proximal tendon retrieval can often be done by “milking” the palm distally, with the wrist and MP joint flexed. If unsuccessful, retrieval can occasionally be done using a tendon retriever, and often the two tendons will advance together. Alternatively, a skin hook can be passed down the tendon sheath past the tendon end, turned to engage the tendon, and then gently withdrawn to advance the tendons. Repeated attempts are unwarranted, and if unsuccessful after one or two tries, an oblique incision over A1 will expose the tendons and allow them to be advanced distally without removal from the sheath. It may be possible to gently pass one of the tendons distally enough to be grasped and brought into the pulley window. The other tendon will usually easily follow. Handle the epitendinous surface as little as possible to discourage future scarring. This process can be aided by passage of a pediatric feeding tube through the pulley into the distal palm. The tendons can be temporarily tied to this and advanced distally. If the tendon cannot be passed under A2 (or A4 in a zone I repair) without “mushrooming,” the sheath of a spinal needle can be modified as seen in Figure 15-7. This can then be used as a “shoehorn” to pass the tendon into the pulley (Gary Kuzma, MD, personal communication). Take care not to rotate the tendons or disrupt their relative positions. Once the proximal tendons are delivered a centimeter into the sheath opening, they can be secured with a 25-g needle placed through the tendons and the A2 pulley. In the distal part of zone II (subdivisions IIa and IIb), the FDS tendon is deep to the FDP and is repaired first. If a single slip is intact, the other one can be excised or repaired. Repair can be done with a 4-0 or 5-0 nonabsorbable polypropylene (Prolene, Ethicon, Bridgewater, NJ) Kessler or Becker suture (Fig. 15-6D). Proximal to Camper's chiasm (zone IIc and IId), FDS can be excised or repaired. More proximally, the repair can be done using a core suture similar to the FDP, as described below. In this case, FDP repair is initiated using a “back-side-first” technique. A 6-0 Prolene suture is placed in a simple, running, epitendinous fashion, beginning at the far side of the tendon (Fig. 15-6E, F). Leave a long tail to tie to later. The sutures should be placed about 2 mm from the cut end and engage about 1 to 2 mm of the thickness of the tendon. Four or five passes should cover the width of the tendon. The knot is buried on the far side and not tied on the near side. This allows approximation P.208 of the tendon ends, improves alignment prior to placement of the core suture, and is much easier to do prior to placement of the core stitch. In addition to “tidying” the repair, this suture can increase the strength of the repair between 10% and 50%.

FIGURE 15-7 Use of a modified spinal needle sheath to create a “shoehorn” to pass the tendon through a pulley. (Courtesy of Gary Kuzma, MD.) A core suture is placed next. We prefer a 4-strand locking cruciate nonabsorbable suture (e.g., polyethylene [FiberWire, Arthrex, Naples, FL] or polyester [TiCron, Covidien, New Haven, CT, or Ethibond, Ethicon, Bridgewater, NJ]) (15). The thin, tapered needle is partially straightened to aid in longitudinal passage through the tendon. The suture is placed in the center of the tendon (central or in the palmar half), exiting 8 to 10 mm from the laceration. The locking stitch is done, and the suture passed down the side of the tendon, across the laceration, and up the side of the other end of the tendon. The locking stitch is placed and the suture brought out through the laceration at the midpoint of the tendon, but the locking loops are left long (Fig. 15-6G). The tendon ends are approximated, and the loops tightened. (This suture will not slide—if there is a gap after this step, start over.) The remainder of the suture can now be placed, with locking loops on both sides of the repair, ending in the middle of the tendon. The suture is tied, making sure to keep the ends approximated, but not over tightening and “bunching” the tendon (Fig. 15-6H). Four square throws with polyester and six with FiberWire are adequate (16). Finally, complete the epitendinous suture around the volar side of the tendon, placing the core suture knot and tails within the repair. The suture can be tied to the long tail left when the epitendinous suture was started (Fig. 15-6I). Note the now normal resting posture of the hand (Fig. 15-6J). Fully flex and extend the digit to make sure the tendon repairs pass under the pulley. Make sure there is no gapping of the repair after a few cycles of passive flexion and extension. (Be sure to remove the 25-g needle placed earlier before doing this!) Following irrigation (and nerve repair if necessary), lay the tendon sheath over the repair and close the skin with interrupted nylon sutures. Use 5-0 fast-absorbing plain gut (Ethicon, Bridgewater, NJ) in children. Place a bulky dressing in the palm (don't wrap the fingers, as the dressings will be much more difficult to remove), and place a palmar short arm splint with the wrist in neutral. Place a dorsal forearm-based splint over this, with the MCP joints flexed and the IP joints extended (Fig. 15-6K).

VARIATIONS IN TECHNIQUE Even in a small area like “no man's land,” there can be considerable variation in the type of injury and the specific surgical techniques required for repair.

Management of FDS lacerations: Recommendations for treatment of FDS lacerations in zone II have ranged from repair to tendon excision, with multiple techniques recommended for repair. In more proximal injuries, excision of a slip or all of the FDS should be considered if the combined repair of the FDP and FDS will not easily pass under the A2 pulley. This is a special problem in zone IIc, just proximal to the split in the FDS tendon and beneath A2, where routine FDS excision may offer a better final result (11). Alternate suture techniques: The goal of any tendon suture is to be strong enough to allow early motion, be flexible enough and have minimal bulk to allow tendon gliding, and be easy enough to do without damaging the tendon. Numerous suture techniques have been proposed for flexor tendon repairs (Fig. 15-8), varying in stiffness; ease and speed of placement; size, location, and number of knots; and suture material. In general, repair strength is related to the thickness and tensile strength of the suture (22) and the number of passes across the tendon repair site. The suture knot may be left in the tendon repair site or incorporated into the tendon distant from the repair, allowing greater surface area for intrinsic tendon healing, as demonstrated in the FDS repair in Figures 15-6D and 15-8G. The epitendinous suture may be placed around the dorsal surface of the tendon prior to core suture placement or may be placed in its entirety first, followed by placement of the core suture (23).

Pulley excision/venting: It is frequently necessary to “vent” either A2 or A4 by making an incision on the pulley's lateral border, either to aid in tendon exposure to allow placement of a core suture (especially in A4) or to allow the tendon repair to pass easily into the pulley system (more commonly A2) (24). While pulley preservation is preferred, venting or complete release of A4 (14) and release of up to the distal 75% of A2 are acceptable to avoid a tendon repair that will trigger or not pass under the pulley (25). Anesthesia: While regional anesthesia is usually used in our practice, “wide awake local anesthesia” (26) or local anesthesia with epinephrine, sedation, and no tourniquet can offer benefits in some patients. Active motion can be tested intraoperatively, as can the tendency of the repair to gap with gentle motion. A repair that gaps or “bunches” can be redone. Management of partial lacerations: Unless noted intraoperatively, diagnosis and quantification of partial flexor tendon injuries in zone II can be difficult. Pain on resisted flexion testing—possibly with a flexion lag—may be the only physical finding. If there is a significant lag and concern about a significant partial laceration, ultrasound may be a useful diagnostic tool (27). P.209

FIGURE 15-8 A limited list of 2-, 4-, and 6-strand repairs. Eight-strand repairs are possible using looped sutures. All of these are combined with a simple epitendinous running “tidying” suture. A: Kessler (Ref. 17). B: Modified Kessler, with knots inside repair. C: Bunnell. D: Strickland (Indiana). E: Modified Becker (MGH) (Ref. 18). F: Four-strand cross-grasping (Adelaide) (Ref. 15). G: Four-strand suture with knot buried in tendon away from repair (Peter Evans MD, PhD, personal communication). H: Six-strand cross-grasping (Ref. 19). I: Six-strand looped suture (Ref. 20). An excellent review of suture techniques can be found in the article by Chauhan et al. (21). Partial lacerations affect tendon function by interfering with gliding of the tendon within the sheath and, to a lesser degree, weakening the tendon. Lacerations on the volar surface of the tendon affect gliding to a greater degree than lateral lacerations (28). Tendon flaps can trigger as they pass the pulleys, even with an intact sheath, with distally oriented oblique lacerations more likely to trigger. Beveling or debridement of lacerations of up to 75% of the tendon thickness is usually adequate, with one study suggesting that immobilization or core suture repair of 60% partial lacerations actually weakened the final tendon strength (29) and another suggesting inferior clinical results (30). Repair is reserved for larger lacerations, and possibly for FDP repairs following FDS

excision. A simple running peripheral repair is usually adequate, although a core suture can be added for highergrade lacerations. Rehabilitation is limited by any complete lacerations that were repaired. For partial injuries alone, an accelerated protected motion program can be initiated, with full active motion allowed from the time of initial presentation, strengthening in 2 to 4 weeks, and unrestricted activity in 4 to 6 weeks, depending on the degree of injury.

Flexor tendon lacerations in children (31,32): While less common than adult injuries, small children present a unique set of challenges. Exposure is through a zigzag Bruner-type incision, as midlateral incisions may cause delayed flexion contractures. Small tendons make core sutures difficult, but two-strand repairs carry a higher rupture risk. A Kessler suture augmented with a horizontal mattress or multiple figure-of-eight sutures can be used, with a simple epitendinous suture. It is difficult to keep the locking sutures far enough from the repair, and the suture knot is often large relative to the size of the tendon. Pulley venting is often required, and the FDS left unrepaired. Rehabilitation protocols will depend on the patient's age and compliance. While active motion programs are preferred, children may do better than adults with immobilization.

PEARLS AND PITFALLS Recognize that the skin laceration may be well proximal to the tendon laceration, especially in injuries that occur with a clinched fist. Do not hesitate to make a small palmar incision, release the A1 pulley, and pass the tendons into the digit if not easily retrieved. This is better than damaging the interior of the tendon sheath or epitenon with repetitive, unsuccessful attempts at retrieval. Maintain alignment and relationship of FDP and FDS. Pay attention to blood vessels on the dorsal side of FDP and to the rotation of the slips of the FDS. P.210 Careful passage of tendons under pulleys. Avoid damaging tendon ends with multiple or rough attempts at passage. “Back-side-first” epitendinous repair is helpful to align tendons and aid in placement of the core suture. Prevent “intussusception” of tendon as the core suture is placed, a problem seen more with thicker or braided sutures. Post-op motion will not be any better than intra-op motion. Make sure there is no “bunching” or gapping at the tendon repair site. Vent or partially excise the pulley if needed. Sheath repair may help or hinder the repair's passage under a pulley. Use thin, tapered needles on the core suture so as not to tear the tendon or damage the epitendinous suture.

POSTOPERATIVE MANAGEMENT Rehabilitation after surgery should promote the biology of tendon healing. Both extrinsic tendon healing (between the tendon and surrounding sheath) and intrinsic tendon healing (direct healing of the tendon ends to each other) occur. Different rehabilitation protocols alter the relative amounts of each type of healing, with immobilization leading to more extrinsic healing and early mobilization leading to less tendon adhesion and more intrinsic healing (33). Early motion programs provide a clear benefit when compared to prolonged immobilization protocols. There is a more rapid improvement in repair tensile strength, increased tendon excursion, less adhesion formation, and less repair site deformation (34). Early motion programs consist of active extension-passive flexion methods, controlled passive motion approaches, early active motion programs, and a combination of the above. The most

effective mobilization strategy remains controversial. A program with gradual motion advancement requires the coordinated effort of the surgeon, a qualified hand therapist, and a cooperative patient to work well. Kleinert first proposed an extension block orthosis equipped with rubber bands, which allowed active digital extension against a constant, passive flexion recoil force (35). Duran and Houser initially used a controlled passive motion protocol at the MP and IP joints, noting that this method afforded 3 to 5 mm of excursion capable of avoiding adhesions (36). Current “active motion” protocols allow active maintenance of passively achieved digital flexion after the wrist has been moved from flexion into extension. While early motion programs allow better and faster recovery of motion, they do not alter the time it takes for the tendon repair to reach full strength. Rather than follow a rigid rehabilitation protocol, we modify the program based on the patient's response to exercise, with the goal of a gradual return to full motion. Patients who are stiffer will advance to more strenuous exercises earlier, while those who are unusually supple or have unusually good early active motion will have more limited active exercises. Therapy is usually initiated within the week following surgical repair. At the first visit, a custommade thermoplastic or off-the-shelf dorsal extension block splint is applied with the wrist neutral, the MP joints flexed 70 to 90 degrees and the IP joints in extension (Fig. 15-9). A palmar bar across P.211 the MP joints will stabilize the hand and keep it from lifting out of the splint. The patient starts with passive motion exercises, bringing the digits into a clenched-fist position with the splint in place. This can be done either passively or with the aid of rubber bands attached to the nail plates, passed through a palmar pulley, and attached to a hook at the wrist. This allows passive flexion, which the patient can actively extend against. Attention must be paid to assure that the patient does not develop interphalangeal joint flexion contractures. A piece of foam placed behind the proximal phalanges in the splint will assure that full PIP extension remains possible.

FIGURE 15-9 An “off-the-shelf” dorsal block splint. The wrist is neutral, the MP joints are flexed, and the IP joints are extended. These can also be custom made by the occupational therapist. Gentle “place and hold” active exercises can begin in the first week for secure four-strand repairs in compliant patients. In other cases, this is delayed until the patient is 3 to 4 weeks from surgery. Actively, the patient maintains the passively achieved fist position as the wrist is brought into 20 to 30 degrees of extension for several seconds. Following this sequence, the patient drops the wrist back into flexion, and the digits are allowed to extend. This cycle is repeated several times per hour each day. High grip forces are discouraged.

After approximately 4 to 6 weeks, the splint is removed for gentle active and passive exercises but worn between exercise sessions. The splint is removed after 6 weeks, at which time more vigorous passive extension exercises and blocking exercises are started. Strengthening is introduced at 8 to 10 weeks postoperatively in a progressive fashion. Prolonged periods of postoperative immobilization with casting are typically avoided, except for unique populations, including children and noncompliant patients. In these patients, a short arm cast (supinated long arm in small children) is applied with the wrist in neutral position. When dry, the cast is extended out over the fingers with the MPs flexed and the IPs extended. The palmar surface of the cast from the MP joints distally is removed to prevent isometric contraction against the cast and to allow a gentle passive program. The cast is continued for 4 to 5 weeks (3 to 4 weeks in small children), at which time active motion without resistance is allowed.

COMPLICATIONS Postoperative stiffness: This can result from tendon adhesion formation, interphalangeal joint contractures, or a combination of both. Adherent tendons do not glide appropriately, leading to decreased active motion with relatively little restriction of passive flexion. A small or moderate flexion contracture may be present. Risk factors for tendon adhesion include immobilization, gapping at the repair site, associated injuries, and trauma to the tendon from the original injury and the following surgical manipulation. Formal occupational therapy, including active motion and strengthening (once it is felt the repair is adequately healed), is helpful. Tenolysis can be considered 4 to 6 months after the initial repair if serial examinations fail to show improvement in active range of motion, if passive range of motion is near full, and if the surrounding bone and soft tissues are satisfactorily healed. Interphalangeal joint contractures: These can occur in any patient but are a special concern in those treated with rubber band traction or immobilization. If identified early, this complication usually resolves after a period of passive stretching and/or static progressive splinting. When significant loss of joint motion remains after 4 to 6 months of dedicated conservative therapy, the patient should be considered for contracture release. This is best performed under a local anesthetic, so that the effectiveness of the release can be assessed and tenolysis can be performed for the almost always coexistent tendon adherence. Tendon rupture: Disruption of the repaired flexor tendons is a serious but uncommon complication, occurring in 2% to 7% of patients, most commonly within the first couple of months following surgery (37,38). Risk factors include the mechanism of injury, quality of repair, presence of infection, rehabilitation protocol, age, and patient compliance. New traumatic insults, excessive movement during rehabilitation exercises, overzealous lifting or gripping motions, and inadvertent actions during sleep can all lead to rupture. Clinical exam typically demonstrates both a lack of strength and active motion. Examination can be difficult, especially early in the postoperative period where digital stiffness may mask a rupture. If suspicious, ultrasound or MRI may aid in diagnosis. Management includes prompt diagnosis, operative exploration, and repair. Tendon passage under the pulleys is more difficult, and the FDS is generally not repaired. Scarring and tendon retraction can complicate repair attempts. The patient and surgeon should be prepared for a possible interpositional graft, arthrodesis, or initiation of a two-stage flexor tendon reconstruction. Infection: This is generally unusual following tendon repair but may result in cases with gross wound contamination on initial presentation. Early irrigation and debridement, followed by resumption of a protected passive motion program is recommended. Depending on surgical findings, early active motion may be discouraged. Delayed treatment is often associated with tendon rupture.

Triggering: Bulky tendon repairs and unrecognized partial tendon lacerations can lead to triggering of the digit. Intraoperative assessment of tendon gliding after repair is important to identify any P.212 resistance or catching as the repair enters or exits the pulley. Pulley venting, partial sheath excision, and tendon “beveling” can help prevent this complication (39). Other complications include iatrogenic neurovascular injuries, chronic regional pain syndromes, and scar contractures.

RESULTS While good to excellent results can be expected in 80% of patients with zone II flexor tendon lacerations (34), many challenges remain in the management of these injuries. In general, results have improved as more secure repair techniques have allowed earlier institution of active motion. Risk factors for a poor result include other associated injuries, such as fracture or nerve lacerations, crush injuries, repair done more than a couple of weeks after the original injury, smoking, and age. Countless contributors have guided our understanding of tendon injuries and repair (34). Our approach to tendon repairs has changed considerably and continuously since Verdan and Kleinert's initial proposal to proceed with primary repair in zone II injuries. Future developments will revolve around a better understanding and individualization of rehabilitation programs, better monitoring of tendon repairs during the postoperative period (e.g., with ultrasound), novel tendon repairs (e.g., barbed, knotless sutures) (40) and novel repair devices (41), and agents to decrease tendon adhesion (34,42,43,44,45). In the meantime, attention to surgical detail; a smooth, strong tendon repair; and a thoughtful, early motion therapy program will provide the best chance of a good or excellent recovery, preventing zone II from becoming McCash's “deathbed of [the] profundus.”

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23. Papandrea R, Seitz WH Jr, Shapiro P, et al.: Biomechanical and clinical evaluation of the epitenon-first technique of flexor tendon repair. J Hand Surg Am 20(2): 261-266, 1995. 24. Kwai Ben I, Elliot D: “Venting” or partial lateral release of the A2 and A4 pulleys after repair of zone 2 flexor tendon injuries. J Hand Surg Br 23(5): 649-654, 1998. 25. Tanaka T, Amadio PC, Zhao C, et al.: The effect of partial A2 pulley excision on gliding resistance and pulley strength in vitro. J Hand Surg Am 29(5): 877-883, 2004. 26. Lalonde DH: Reconstruction of the hand with wide awake surgery. Clin Plast Surg 38(4):761-769, 2011. P.213 27. Lee DH, Robbin ML, Galliott R, et al.: Ultrasound evaluation of flexor tendon lacerations. J Hand Surg Am 25(2): 236-241, 2000. 28. Erhard L, Zobitz ME, Zhao C, et al.: Treatment of partial lacerations in flexor tendons by trimming. A biomechanical in vitro study. J Bone Joint Surg Am 84-A(6): 1006-1012, 2002. 29. Bishop AT, Cooney WP III, Wood MB: Treatment of partial flexor tendon lacerations: the effect of tenorrhaphy and early protected mobilization. J Trauma 26(4): 301-312, 1986. 30. McGeorge DD, Stilwell JH: Partial flexor tendon injuries: to repair or not. J Hand Surg Br 17(2): 176-177, 1992. 31. Al-Qattan MM: Flexor tendon injuries in the child. J Hand Surg Eur Vol 39(1): 46-53, 2014. 32. Nietosvaara Y, Lindfors NC, Palmu S, et al.: Flexor tendon injuries in pediatric patients. J Hand Surg Am 32(10): 1549-1557, 2007. 33. Gelberman RH, Woo S, Amiel D, et al.: Influences of flexor sheath continuity and early motion on tendon healing in dogs. J Hand Surg 15(A): 66-77, 1990. 34. Strickland JW: Development of flexor tendon surgery: twenty-five years of progress. J Hand Surg Am 25(2): 214-235, 2000. 35. Kleinert HE, Kutz JE, Atasoy E, et al.: Primary repair of flexor tendons. Orthop Clin North Am 4(4): 865876, 1973. 36. Duran RJ, Houser RG: Controlled passive motion following flexor tendon repair in zones II and III. In: Hooper G, ed. AAOS symposium on tendon surgery of the hand. St. Louis, CA: C.V. Mosby, 1975: 105-114. 37. Harris SB, Harris D, Foster AJ, et al.: The aetiology of acute rupture of flexor tendon repairs in zones 1 and 2 of the fingers during early mobilization. J Hand Surg Br 24(3): 275-280, 1999.

38. Dy CJ, Daluiski A, Do HT, et al.: The epidemiology of reoperation after flexor tendon repair. J Hand Surg Am 37(5): 919-924, 2012. 39. Momeni A, Grauel E, Chang J: Complications after flexor tendon injuries. Hand Clin 26(2): 179-189, 2010. 40. Peltz TS, Haddad R, Scougall PJ, et al.: Performance of a knotless four-strand flexor tendon repair with a unidirectional barbed suture device: a dynamic ex vivo comparison. J Hand Surg Eur Vol 39(1): 30-39, 2014. 41. Su BW, Solomons M, Barrow A, et al.: Device for zone-II flexor tendon repair. A multicenter, randomized, blinded, clinical trial. J Bone Joint Surg Am 87(5): 923-935, 2005. 42. Baymurat AC, Ozturk AM, Yetkin H, et al.: Bio-engineered synovial membrane to prevent tendon adhesions in rabbit flexor tendon model. J Biomed Mater Res A 103(1): 84-90, 2015. 43. Zhao C, Sun YL, Kirk RL, et al.: Effects of a lubricin-containing compound on the results of flexor tendon repair in a canine model in vivo. J Bone Joint Surg Am 92(6): 1453-1461, 2010. 44. Zhao C, Wei Z, Reisdorf RL, et al.: The effects of biological lubricating molecules on flexor tendon reconstruction in a canine allograft model in vivo. Plast Reconstr Surg 133(5): 628e-637e, 2014. 45. Zhao C, Sun YL, Jay GD, et al.: Surface modification counteracts adverse effects associated with immobilization after flexor tendon repair. J Orthop Res 30(12): 1940-1944, 2012.

Chapter 16 One- and Two-Stage Reconstructive Approaches for Intercalary Flexor Tendon Deficiency Michael W. Neumeister Brian M. Derby Bradon J. Wilhelmi

INTRODUCTION Tendon lacerations in the hand are common. Primary tendon repair follows the principles of tendon repair that have evolved to today's debates on repair techniques, core suture number, and early mobilization (1,2). However, primary end-to-end repair is occasionally not possible and tendon grafting is needed. Alternatively, the desired outcome of the primary repair is unacceptable, and secondary procedures are required to restore function. The secondary procedures may include tenolysis, tendon transfer, tendon grafting (single- and twostage approaches), and pulley reconstruction. Tenolysis alone to restore function requires and intact tendon and pulley system. Intercalary tendon grafting is needed when the substance of the tendon is absent. Lexer reported on the first series of flexor tendon graft use in the hand in 1912 (3). In 1963, Basset and Carroll described secondary reconstruction of tendons using silicone implants. Later in 1971, Hunter expanded upon the staged technique of flexor tendon reconstruction (4). Intercalary tendon grafting and pulley reconstruction are discussed in detail in the pages that follow.

INDICATIONS AND CONTRAINDICATIONS Tenolysis procedures are occasionally required to release adherent tendons from the bone or surrounding soft tissue. The fingers usually have good passive motion but poor active motion. Periarticular contractures may also contribute to poor motion at the metacarpal (MP) or interphalangeal (IP) P.216 joints (proximal interphalangeal, PIP, and distal phalangeal, DIP). Complete release of all offending restrictive soft tissue fibrosis will aid in the postoperative active and passive range of motion (4,5,6,7,8). The timing of tenolysis after primary repair, or reconstructive grafting, has been controversial. Most authors recommend waiting 3 months after the initial surgery and when therapy plateaus before embarking upon tenolysis (2,6,8). Prior to this tenolysis may endanger nutritional supply and increase risk of rupture (8). Intercalary tendon grafting can be divided up into two groups: single stage, which is generally considered acute (primary), and two stage, which is delayed (secondary) (4). The indications for acute single-stage free tendon graft are limited (4) (Table 16-1). Outside of these narrow parameters for acute single-stage graft repair, twostage tendon grafting is performed. Boyes provided a preoperative injury classification system meant to aid in decision making for primary or secondary tendon grafting (8,9,10) (Table 16-2). Outside of Boyes' level 1, most tendon grafting (Boyes' levels 2 to 5) will need a staged reconstruction. In general terms, most surgeons use the criteria in Table 16-3 for their indications for staged tendon grafting. Contraindications to tendon grafting are included in Table 16-4 (2,3,4). In an attempt to salvage useful finger function in more significantly damaged fingers (Boyes' grades 2 to 5), two-stage reconstruction should be pursued. Also, if the pulley systems require reconstruction, single-stage reconstruction should be abandoned, and efforts turned to two-stage reconstruction (2). With all of this information in mind, a well-informed consent is fundamental. Each patient needs to understand that an intraoperative evaluation of the tendons during tenolysis procedures, primary tendon repair or grafting, or joint releases may require a staged reconstruction to provide

the optimum result.

TABLE 16-1 Indications for Acute Single-Stage Free Tendon Graft 1. Injuries resulting in segmental tendon loss 2. Delayed presentation greater than 3 weeks, resulting in tendon end fraying and retraction from muscle belly contraction 3. Delayed presentation of some FDP avulsion injuries

TABLE 16-2 Boyes Injury Classification for Tendon Grafting Grade 1—Minimum scar, supple joints, no trophic changes Grade 2—Scar limiting gliding of graft Grade 3—Joint involvement with loss of passive motion Grade 4—Multiple digit involvement with tendon injury Grade 5—Devastating injury with salvage procedures required

TABLE 16-3 Indications for Flexor Tendon Grafting 1. Late rupture of flexor repair 2. Rupture or gap at tenolysis 3. Late presentation after injury

TABLE 16-4 Contraindications to Tendon Grafting 1. Insensate digit

2. Poorly vascularized fingers 3. Patients who cannot appreciate the needs for strict adherence to postoperative hand therapy regimens (i.e., children