Hip Arthroplasty: Current and Future Directions 9819955165, 9789819955169

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Hip Arthroplasty Current and Future Directions Mrinal Sharma Editor

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Hip Arthroplasty

Mrinal Sharma Editor

Hip Arthroplasty Current and Future Directions

Editor Mrinal Sharma Head of Orthopedics and Joint Replacement Amrita Institute of Medical Sciences Amrita Vishwavidyapeetham Faridabad, India

ISBN 978-981-99-5516-9    ISBN 978-981-99-5517-6 (eBook) https://doi.org/10.1007/978-981-99-5517-6 © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 This work is subject to copyright. All rights are solely and exclusively licensed by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors, and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. This Springer imprint is published by the registered company Springer Nature Singapore Pte Ltd. The registered company address is: 152 Beach Road, #21-01/04 Gateway East, Singapore 189721, Singapore Paper in this product is recyclable.

This book is dedicated to my wife Dr Shalini Sharma and my children Saanvi and Manan.

Foreword

Books are a man’s best friend—is a well-known phrase. My young colleague Dr Mrinal Sharma has gone beyond his years to produce this beautiful magnum. Arthroplasty has been a dynamically evolving art and what was considered the latest yesterday is today the story of the past. Newer techniques, materials, and innovations make it a challenge to keep up with the advancement in any field, particularly in joint replacement. Mrinal has divided his volume into six parts covering from primary total hip to complex situations, implants, and tribology to navigation and revision scenarios. The book has been developed with the help and chapters written by a galaxy of arthroplasty surgeons with cumulative experience of many hundred years. This gives a wonderful opportunity to anybody interested in the field of Hip Replacement to read this volume as a text and position it on their shelves for reference whenever required. I wish him success and congratulate him on completing this Yeoman task. S. K. S. Marya Dept of Orthopedics, Max Hospital Saket Delhi, India 

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Foreword

I first met Mrinal when he was doing a Travelling Fellowship in the UK and his passion for arthroplasty and precision was clearly visible at that early stage itself, and there was no doubt that he was destined for greater things in life! It, therefore, gives me immense pleasure to write a Foreword for his book entitled, Hip Arthroplasty: Current and Future Directions. I congratulate Mrinal for putting together this comprehensive text, which provides a state-of-the-art review of evidence-informed management of hip pathology. With the explosion of information on hip pathology in the literature, particularly in the management of the young adult, this book is very timely and offers a comprehensive treatise in this arena. This book is unique in the fact that it is all encompassing and covers the basics and in-depth operative details about primary, complex primary, and revision total hip arthroplasty. There is a whole section dedicated to basic sciences and covers the design aspect of the prosthesis and tribology as well. The section on complications after a total hip arthroplasty and management thereof has been handled extremely well. Finally, the section on future advances covering the use of technology (Navigation and Robotics) in hip arthroplasty is very inspiring not only for the practicing hip surgeon but also for any trainee interested in orthopedic surgery. As anyone who has written a book of this magnitude would appreciate, selecting and coordinating international authors for different chapters, getting relevant permissions, editing, and ensuring that the central message is not lost and liaising with the publishers is a mammoth task. I believe the editor has managed this task extremely well drawing in from the experience of more than 50 authors who are leading experts in this field contributing a total of 63 chapters with over 400 color drawings and photographs.

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Foreword

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I believe that this textbook does provide comprehensive information in an efficient manner resulting in an invaluable aide-memoire in clinic and the operating theater and a reference text at home. I do sincerely hope that the readers enjoy reading the book as much as the team has enjoyed putting it together, and this enables them to deliver excellent care for patients with hip pathology globally. Addenbrooke’s Hospital Cambridge, UK

Vikas Khanduja,

Foreword

Total hip replacement has been termed the “operation of the century” since the last century but continues to improve in terms of outcomes and patient satisfaction, as it moves from the treatment of the elderly disabled to the younger patient who has failed non-operative management and is seeking an improved quality of life. Length of stay is transitioning from 2 weeks of inpatient stay to day surgery procedures and longevity of modern implants will see prosthesis in situ for over 30 years. My fascination with the topic over 20 years of surgical practice is the look of relief on patients’ faces when they return for review at the 6-week mark following surgery. It is an ongoing source of inspiration to continue to pursue best practices for the benefit of our patients. My career path has seen me travel extensively to teach (and learn) and many trips to India have allowed me to observe the enormous strides forward, made in surgical practice over the last decade and a half. On a recent venture to another fact-filled conference and live surgery extravaganza, I was asked by the editor if I would write the foreword for this text and of course, I would oblige. This text on Hip Arthroplasty: Current and Future Directions has been prepared to deliver core foundation material for the new surgeon and early career surgeon covering the many aspects of total hip replacement that is a must-read by clinicians before embarking on this journey. The editor and author of this text is now well-known to me as we have shared the stage on a few occasions in India. Well-trained himself, with an excellent postgraduate accreditation and over a decade of experience in hip arthroplasty, he has aligned a wealth of talent from India and abroad to contribute individual chapters to this comprehensive study of the current practice in hip replacexi

Foreword

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ment surgery. Many of the chapter authors are also well-known to me from my travels overseas over the last two decades for academic endeavors, and these authors are all very well positioned in their collective wisdom on the subjects presented. Of particular interest are the chapters on “Hip biomechanics,” “Implant selection rationale and use,” “Robotic hip replacement,” and “Revision of acetabular components uncemented cups and augments” just to name a few, but each chapter has a credible evidence base to satisfy the reader. Having been involved in the art of writing book chapters but, more importantly, in the process of being an editor for a textbook, I know that assembling the vast array of inputs, as has been completed here, is certainly not easy and requires patience and perseverance over a period of time that is much longer than originally planned. So now that it has been executed the beneficiary will certainly be the reader who has a one-stop shop for enhancing the core knowledge on hip replacement surgery. It is to the benefit of our patients that knowledge is shared and both techniques and materials are continually improved so that total hip replacement also remains the operation of the current century. Nepean Private Hospital Macquarie University Hospital, Kingswood, NSW, Australia

Rami Sorial

Preface

Medicine is ever on the march, so do openings in operation of the HIP—the keelson of human-ship.

Total hip arthroplasty has rightly been called the “Operation of the Century” as it has given pain-free mobility to thousands and lakhs who suffered from hip joint arthritis. The art of hip arthroplasty has been evolving ever since its inception and has seen a paradigm shift from small diameter low-friction metal head cemented hip arthroplasty to large diameter ceramic head uncemented hip arthroplasty. Advances in metallurgy, surgical techniques, innovations in prosthesis designs, and technology have tremendously improved the outcomes after total hip arthroplasty. My book HIP Arthroplasty: Current and Future Directions covers A to Z in the basics of primary, complex primary, and revision hip arthroplasty. The section on basic primary hip arthroplasty has been written keeping in mind the beginner arthroplasty surgeons and covers preoperative planning to the radiological evaluation of hip arthroplasty. Basic approaches in THA and surgical steps have been described in detail in this section. Tribology, prosthesis design, and rationale for use have been discussed in the second section of the book. Hip arthroplasty in all complex scenarios has been described in detail in another section. A separate section for complications has been included to discuss the causes, prevention, and management in detail. Robotics and navigation-assisted hip arthroplasty holds the future and is a great research tool that has been described in detail. The last section discusses revision hip arthroplasty covering failure modes, prosthesis selection, and management of acetabular and femoral bone loss comprehensively. The chapters are a gist of the lifetime experience of the contributing authors who have shared practical and published knowledge. The content is lucid and has colorful pictorial representations of surgical steps. Case discussions and surgical pearls have been incorporated. The discussion includes a comprehensive review of the recent literature and will be helpful to those doing research. The book is a must-read for beginner arthroplasty surgeon’s and will serve as a useful coffee table reference book for the master arthroplasty surgeons. Faridabad, India

Mrinal Sharma

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Acknowledgment

Arthroplasty is my passion, and I would like to thank the almighty for giving me a chance to give it back to my specialty and contribute in the form of this book. I am deeply indebted to all the authors who have contributed their lifetime experience in the respective chapters they have authored. I would like to pay deep regards to my parents Prof Dr N K Sharma and Mrs Yogesh Sharma for making me a hard-working and learned Orthopedician. I would like to thank my wife Dr Shalini Sharma for believing in me and motivating me. Without her moral support and help, this book would not have been possible. I would like to thank my teachers and mentors Dr C S Ranawat, Dr Amar Ranawat, Dr Kamaldeep, Dr Frederic Picard, Dr C S Sharma, Prof Sudhir Kumar and many more who have contributed to my professional growth. I would also like to thank Dr SKS Marya, Dr Vikas Khanduja, and Dr Rami Sorial who agreed to write a foreword for my book. I would extend my sincere thanks to the whole team of Springer including Mr. Naren Aggarwal, Mrs. Raman, and Mr. Kumar Athiappan, without whose support this book would not have been in its present form. I take responsibility for any errors in the book. Mrinal Sharma

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Contents

Part I Primary Total Hip Arthroplasty 1 Hip  Biomechanics and Preoperative Assessment in Total Hip Arthroplasty ������������������������������������������������������������������������������������   3 Lalit Maini 2 D  irect Anterior Approach Total Hip Arthroplasty������������������������  13 Phonthakorn Panichkul, Kanokpol Tanakritrungtawee, and Kamolsak Sukhonthamarn 3 Direct  Lateral Approach to the Hip ����������������������������������������������  31 Raju Vaishya, Y. S. Suresh Babu, and Abhishek Vaish 4 Posterior Approach in Total Hip Arthroplasty������������������������������  41 Sunil Gurpur Kini and Mrinal Sharma 5 Cemented Total Hip Arthroplasty��������������������������������������������������  49 Indrajeet Sardar, Rajeev Raman, and Mrinal Sharma 6 Cementless Total Hip Arthroplasty������������������������������������������������  61 Mrinal Sharma 7 Hybrid Total Hip Replacement������������������������������������������������������  93 Sameer Aggarwal, Mandeep Singh Dhillon, and Prasoon Kumar 8 Bipolar  Hemiarthroplasty for Fracture Neck Femur������������������ 103 Narendra Joshi and Rakesh Kumar Dhukia 9 Minimally Invasive Total Hip Arthroplasty���������������������������������� 113 Caesar Wek, Ed Massa, and Venu Kavarthapu 10 Radiological Assessment in Total Hip Arthroplasty��������������������� 127 Praharsha Mulpur, Adarsh Annapareddy, and A. V. Guravareddy Part II Implants and Tribology 11 Bearing  Surfaces in Total Hip Arthroplasty���������������������������������� 153 Vivek Logani

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12 Polyethylene  Cups in Total Hip Arthroplasty�������������������������������� 163 Shobit Deshmukh and Vaibhav Bagaria 13 Cementless  Cups in Total Hip Arthroplasty���������������������������������� 171 Narendra V. Vaidya and Tanmay N. Jaysingani 14 Femoral  Stems in Total Hip Arthroplasty�������������������������������������� 183 Vivek Mahajan, H. Kantharaju, and Mrinal Sharma 15 Implant  Selection and Rationale for Use in Primary Total Hip Arthroplasty�������������������������������������������������������������������� 193 Rajesh Malhotra, Deepak Gautam, and Alok Rai Part III Total Hip Arthroplasty in Complex Scenario 16 Total  Hip Arthroplasty in Avascular Necrosis of Hip ������������������ 219 Shitij Kacker and S. K. S. Marya 17 Total  Hip Arthroplasty in Dysplastic Hips������������������������������������ 235 Vijay C. Bose, Kalaivanan Kanniyan, and Alex Muttathupadam 18 H  ip Arthroplasty for Inter-­Trochanteric Fractures in Elderly������������������������������������������������������������������������������������������ 247 Rajeev Joshi, Dheeraj Attarde, and Sahil Sanghavi 19 Total  Hip Arthroplasty in Ankylosed/Fused Hips ������������������������ 263 Pradeep B. Bhosale, Pravin Uttam Jadhav, and Vijaysing Shankar Chandele 20 Total  Hip Arthroplasty for Protrusio Acetabuli: Principles of Reconstruction and Technique�������������������������������������������������������� 285 Abhay Elhence, Sumit Banerjee, and Akshat Gupta 21 Total  hip Arthroplasty in Tubercular Hip Arthritis���������������������� 301 Anil Arora, Bushu Harna, and Deepak Gupta 22 Total  Hip Arthroplasty in Proximal Femoral Deformity�������������� 315 N. Rajkumar and D. Soundarrajan 23 Total  Hip Replacement After Acetabulum Fractures ������������������ 327 Ramesh K. Sen, Milkias Tsehaye, and Sujit Kumar Tripathy 24 C  onversion Total Hip Arthroplasty Following Failed Fixation���������������������������������������������������������������������������������� 337 Jason Zlotnicki, Samuel Rodriguez, and Amar S. Ranawat 25 Total  Hip Arthroplasty for Fracture Neck of Femur�������������������� 347 Mrinal Sharma 26 Total  Hip Replacement in Rheumatoid Arthritis�������������������������� 359 S. K. S. Marya, Chandeep Singh, and Sameer Kakar

Contents

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27 Total  Hip Arthroplasty in Neglected Hip Dislocations ���������������� 373 Harpreet Singh Gill, Dheeraj Attarde, and Mrinal Sharma 28 Conversion  of Excision Arthroplasty to Total Hip Arthroplasty������������������������������������������������������������������������������ 385 Rajeev Joshi, Dheeraj Attarde, and Sahil Sanghavi 29 Juvenile  Rheumatoid Arthritis and Total Hip Arthroplasty�������� 391 I. P. S. Oberoi, Satvir Singh, and Abhishek Choudhary Part IV Complications in Total Hip Replacement 30 Periprosthetic Fracture After Total Hip Arthroplasty������������������ 399 Mayur Nayak and Rohit Rambani 31 I nstability After Total Hip Replacement: Aetiology, Prevention and Management���������������������������������������������������������� 413 Buddha Deb Chatterjee 32 Management  of Limb Length Discrepancy in Total Hip Arthroplasty ������������������������������������������������������������������������������������ 431 Subhash Jangid and Manas Chandra 33 Heterotopic  Ossification Following Hip Replacement������������������ 445 Amrit Goyal and Jeffrey A. Geller 34 Management  of Sciatic Nerve Palsy After a Total Hip Arthroplasty ������������������������������������������������������������������������������������ 453 Ishu Goyal and Manish Mahajan 35 Trunnionosis in Total Hip Arthroplasty���������������������������������������� 465 Mustafa Akkaya, Thorsten Gehrke, and Mustafa Citak 36 Single-Stage  Revision for a Prosthetic Joint Infection After Total Hip Arthroplasty�������������������������������������������������������������������� 473 Warran Wignadasan, Mazin Ibrahim, and Fares S. Haddad 37 Two-Stage  Revision for an Infected Total Hip Arthroplasty�������� 483 Shubhranshu S. Mohanty and Sameer Panchal Part V Navigation and Robotics in Total Hip Arthroplasty 38 Computer-Assisted  Navigation in Total Hip Arthroplasty���������� 495 Kamal Deep and Frederic Picard 39 Overview  of Robotics in Total Hip Arthroplasty�������������������������� 503 James A. Dalrymple, Mazin S. Ibrahim, Babar Kayani, Ajay K. Asokan, and Fares S. Haddad Part VI Revision Total Hip Arthroplasty 40 Modes  of Failure in Total Hip Arthroplasty���������������������������������� 517 Chandra Shekhar Yadav and Sumit Anand

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41 Surgical  Exposure in Revision Hip Arthroplasty: A Step-Wise Approach�������������������������������������������������������������������� 537 Samuel Rodriguez, Jose A. Rodriguez, and Amar S. Ranawat 42 Acetabular  Component Extraction in Revision Hip Surgery������ 547 Satish Dhotare and Nikhil Shah 43 Removal  of Femoral Stem During Revision Hip Arthroplasty���� 559 Chandrashekhar Sahebrao Sonawane and Mahesh Madhukar Kulkarni 44 Implant  Selection in Revision Total Hip Arthroplasty ���������������� 567 Praharsha Mulpur, A. B. Suhas Masilamani, and A. V. Guravareddy 45 Dual  Mobility Cups in Primary and Revision Total Hip Arthroplasty ������������������������������������������������������������������������������������ 583 Ramneek Mahajan, Piyush Nashikkar, and Varun Khanna 46 Acetabular  Revision in Total Hip Arthroplasty: Porous Metal Cups and Augments�������������������������������������������������������������� 597 Gregory Minutillo, Kevin Pirruccio, Aaron Gebrelul, and Neil P. Sheth 47 Structural  Bone Grafts in Primary and Revision Total Hip Arthroplasty ������������������������������������������������������������������������������������ 607 Shobit Deshmukh, Anjali Tiwari, and Vaibhav Bagaria 48 Impaction  Bone Grafting for Management of Acetabular Bone Defects in Revision Total Hip Arthroplasty ���������������������������������� 617 Ramesh K. Sen and Sujit Kumar Tripathy 49 Revision  of Acetabulum Using Rings and Cages�������������������������� 629 Avtar Singh, Rajeev Vohra, and Babaji Sitaram Thorat 50 Acetabular  Constraints in Revision Hip Arthroplasty ���������������� 649 Raju Vaishya, Y. S. Suresh Babu, and Abhishek Vaish 51 Chronic Pelvic Discontinuity���������������������������������������������������������� 657 Aaron Gebrelul, Kevin Pirruccio, Brian Velasco, Gregory Minutillo, and Neil P. Sheth 52 Jumbo  Cups in Revision Total Hip Arthroplasty�������������������������� 677 Anil Thomas Oommen 53 Femoral  Component Revision Using Impaction Bone Grafting and a Cemented Stem������������������������������������������������������ 685 Nuthan Jagadeesh, Henry Wynn Jones, Bodo Purbach, and Nikhil Shah 54 Cement-in-Cement  Technique for Revision of the Femoral Stem�������������������������������������������������������������������������������������������������� 697 Yatinder Kharbanda, Y. S. Suresh Babu, and Ross Crawford

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55 Uncemented  Tapered Femoral Stems in Revision Total Hip Arthroplasty ������������������������������������������������������������������������������������ 707 Praharsha Mulpur, Adarsh Annapareddy, and A. V. Gurava Reddy 56 Proximal  Porous Coated Modular Metaphyseal Stems in Primary and Revision THA�������������������������������������������������������� 719 Dhanasekararaja Palanisami, Soundar Dhanasekaran, Rajkumar Natesan, and Rajasekaran Shanmuganathan 57 Extensively  Porous Coated Stems in Revision Total Hip Arthroplasty ������������������������������������������������������������������������������������ 733 Mrinal Sharma, Bharat Dhanjani, and Vijay Kumar 58 Custom  Prostheses for Acetabular Reconstruction in Revision Hip Arthroplasty���������������������������������������������������������� 749 David Hillier, Henry Wynn Jones, and Nikhil Shah 59 Megaprosthesis  Reconstruction as a Salvage Option for Revision THR ���������������������������������������������������������������������������� 759 Wolfgang Klauser and Jörg Löwe 60 Conversion  of Failed Hemiarthroplasty to Total Hip Arthroplasty������������������������������������������������������������������������������ 775 Harish S. Bhende and Prakash K. George 61 Allograft  Prosthetic Reconstruction in Revision Total Hip Arthroplasty ������������������������������������������������������������������������������������ 789 Chetan Sood and Santhosh Kumar 62 Re-revision Total Hip Arthroplasty������������������������������������������������ 811 Pichai Suryanarayan, Kalaivanan Kanniyan, and Vijay C. Bose 63 The  Past, Present and Future of Hip Arthroplasty���������������������� 825 Sianne E. T. Toemoe, Victor Lu, Parminder J. Singh, and Vikas Khanduja

Editor and Contributors

About the Editor Mrinal  Sharma, MBBS. MS, DNB, MCH. ORTHO  Dr. Mrinal Sharma is a Senior Joint Replacement Surgeon and Head of Orthopedics and Joint Replacement Surgery at Amrita Institute of Medical Sciences, Amrita Vishwavidyapeetham, Faridabad, and specializes in primary and revision knee and hip arthroplasty. He has already written a book entitled Knee Arthroplasty: New and Future Directions and has now worked hard to produce another masterpiece on hip arthroplasty. After completing his master’s in orthopedics from SMS Medical College, Jaipur, he went abroad and was extensively trained in joint replacement surgery in many countries including the USA (Ranawat Fellowship), the UK (SICOT Navigation Fellowship, IOS UK fellowship), and Germany (Revision Arthroplasty Fellowship). He has been the First Ambassador of the Indian Orthopedic Association to Singapore. He has also many domestic fellowships like Ludhiana Travelling Fellowship, Sancheti Institute Fellowship, Delhi Orthopedic Association Fellowship, and Stryker Joint Replacement Fellowship. He is the proud recipient of Ayushman India Award, SICOT India Foundation Award, MP Chapter Gold Medal Award, and KT Dholakia Award of IOA. Dr. Mrinal Sharma is the executive member of the SICOT Hip Committee, SICOT Educational Committee, Indian Arthroplasty Association, and Delhi Orthopedic Association. He is also an active member of the Indian Society of Hip and Knee Surgeons, Asia Pacific Arthroplasty Association, and the Indian Orthopedic Association. Dr. Mrinal Sharma is on the editorial board (Associate Editor) of the Journal of Clinical Orthopaedics and Trauma and has been a reviewer for the Indian Journal of Orthopaedics and British Medical Journal.

Contributors Sameer  Aggarwal Department of Orthopaedics, PGIMER, Chandigarh, India Mustafa  Akkaya Department of Orthopedic Surgery, ENDO-Klinik Hamburg, Hamburg, Germany xxiii

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Sumit  Anand Joint Replacement Department, Primus Superspeciality Hospital, New Delhi, India Adarsh  Annapareddy Sunshine Bone and Joint Institute, Sunshine Hospitals, Hyderabad, Telangana, India Anil  Arora Department of Orthopaedics and Joint Replacement, Max Superspeciality Hospital, Patparganj, New Delhi, Delhi, India Prof. Arora’s Knee and Hip Surgery Clinics, New Delhi, Delhi NCR, India Ajay K. Asokan  University College London Hospitals, London, UK Dheeraj  Attarde Sancheti Institute of Orthopaedics and Rehabilitation, Pune, Maharashtra, India Y. S. Suresh Babu  Indraprastha Apollo Hospitals, New Delhi, India Vaibhav  Bagaria Sir H.N.  Reliance-Foundation Hospital and Research Centre, Mumbai, Maharashtra, India Sumit Banerjee  AIIMS Jodhpur, Jodhpur, India Harish  S.  Bhende Center for Joint Replacement Surgery—Laud Clinic, Mumbai, Maharashtra, India Pradeep  B.  Bhosale Nanavati Max Super Speciality Hospital, Mumbai, India Maharashtra University of Health Sciences (MUHS), Nashik, India Vijay C. Bose  Asian Orthopaedic Institute, Chennai, Tamil Nadu, India Vijaysing  Shankar  Chandele Nanavati Max Super Speciality Hospital, Mumbai, India Maharashtra University of Health Sciences (MUHS), Nashik, India Manas  Chandra Bone and Joint Institute, Fortis Memorial Research Institute, Gurugram, Haryana, India Buddha  Deb  Chatterjee Director Orthopaedics, Apollo Multispeciality Hospitals, Kolkata, India Abhishek Choudhary  Joint Replacement and Sports injury Unit, Artemis Hospital, Gurgaon, Haryana, India Mustafa Citak  Department of Orthopedic Surgery, ENDO-Klinik Hamburg, Hamburg, Germany Ross Crawford  Indraprastha Apollo Hospitals, New Delhi, India Queensland University of Technology, Brisbane City, Australia The Prince Charles Hospital and St. Vincents Northside Private Hospital, Chermside, QLD, Australia James A. Dalrymple  University College London Hospitals, London, UK Kamal Deep  Golden Jubilee National Hospital, Glasgow, UK

Editor and Contributors

Editor and Contributors

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Shobit  Deshmukh Sir H.N.  Reliance Foundation Hospital and Research Centre, Mumbai, Maharashtra, India Soundar  Dhanasekaran Department of Orthopaedic Surgery, Ganga Hospital, Coimbatore, Tamil Nadu, India Bharat  Dhanjani Department of Orthopaedics, Rungta Hospital, Jaipur, Rajasthan, India Mandeep  Singh  Dhillon  Department Chandigarh, India

of

Orthopaedics,

PGIMER,

Satish Dhotare  Centre for Hip Surgery, Wrightington Hospital, Wigan, UK Rakesh  Kumar  Dhukia Sawai Man Singh Medical College & Attached Hospitals, Jaipur, Rajasthan, India Abhay Elhence  AIIMS Jodhpur, Jodhpur, India Deepak Gautam  Medicover Hospitals, Navi Mumbai, India Aaron Gebrelul  The Anderson Orthopaedic Clinic, Arlington, VA, USA Thorsten  Gehrke Department of Orthopedic Surgery, ENDO-Klinik Hamburg, Hamburg, Germany Jeffrey A. Geller, MD  Department of Orthopedic Surgery, NYP-Lawrence Hospital Westchester, Bronxville, NY, USA Division of Hip and Knee Reconstruction-Columbia University Medical Center, New York, NY, USA Prakash  K.  George  Center for Joint Replacement Surgery—Laud Clinic, Mumbai, Maharashtra, India Harpreet Singh Gill  Orthopaedic & Joint replacement surgeon, Ludhiana, Punjab, India Amrit Goyal, MS  Department of Orthopedic Surgery, S.N. Medical College, Agra, Uttar Pradesh, India Ishu  Goyal Department of Neurology, Agrim Institute of Neurosciences, Artemis Hospitals, Gurugram, Haryana, India Akshat Gupta  AIIMS Jodhpur, Jodhpur, India Deepak  Gupta Max Superspeciality Hospital, Patparganj, New Delhi, Delhi, India A. V. Guravareddy  Sunshine Bone and Joint Institute, Sunshine Hospitals, Hyderabad, India Fares S. Haddad  University College London Hospitals, London, UK Bushu  Harna Department of Orthopaedics, Indus International Hospital, Mohali, India

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David  Hillier Liverpool University Hospitals, NHS Foundation Trust, Liverpool, UK Mazin S. Ibrahim  University College London Hospitals, London, UK Pravin Uttam Jadhav  Nanavati Max Super Speciality Hospital, Mumbai, India Maharashtra University of Health Sciences (MUHS), Nashik, India Nuthan Jagadeesh  Wrightington Hospital, Wigan, UK Subhash  Jangid Bone and Joint Institute, Fortis Memorial Research Institute, Gurugram, Haryana, India Tanmay N. Jaysingani  Lokmanya Group of Hospitals, Pune, India Henry Wynn Jones  Wrightington Hospital, Wigan, UK Centre for Hip Surgery, Wrightington Hospital, Wigan, UK Narendra Joshi  Sawai Man Singh Medical College & Attached Hospitals, Jaipur, Rajasthan, India Rajeev Joshi  Sancheti Institute for Orthopaedics and Rehabilitation, Pune, India Shitij  Kacker Max Institute of Musculoskeletal Sciences, Max Hospital, Saket, Gurugram, India Sameer  Kakar  Max Institute of Musculoskeletal Sciences, Max Hospital Saket, New Delhi, Delhi, India Max Institute of Musculoskeletal Sciences, Max Hospital Gurugram, Gurugram, Haryana, India Kalaivanan Kanniyan  Asian Orthopaedic Institute, Chennai, India Asian Orthopedic Institute, AOI @ SIMS Hospitals, Chennai, Tamil Nadu, India H. Kantharaju  Indian Spinal Injuries Center (ISIC), New Delhi, India Venu Kavarthapu  King’s College Hospital, London, UK Babar Kayani  University College London Hospitals, London, UK Vikas Khanduja  Department of Trauma and Orthopaedics, Addenbrooke’s— Cambridge University Hospital, Cambridge, UK Varun Khanna  Sir Ganga Ram Hospital, New Delhi, India Yatinder Kharbanda  Indraprastha Apollo Hospitals, New Delhi, India Sunil Gurpur Kini  Joint Replacement/Arthroscopy/Adult Reconstruction, Manipal Hospitals, Bangalore, India Wolfgang Klauser  VAMED Ostseeklinik Damp, Damp, Germany

Editor and Contributors

Editor and Contributors

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Mahesh  Madhukar  Kulkarni Department of Joint Replacement and Reconstruction, Deenanath Mangeshkar Hospital and Research Center, Pune, India Prasoon Kumar  Department of Orthopaedics, PGIMER, Chandigarh, India Santhosh Kumar  JRC, Army Hospital (Research & Referral), New Delhi, India Vijay Kumar  Department of Orthopaedics and Joint Replacement, Amrita Institute of Medical Sciences, Amrita Vishwa Vidyapeetham, Coimbatore, Tamil Nadu, India Vivek  Logani Paras Joint Replacement & Sports Injury Centre, Paras Hospitals, Gurugram, Delhi NCR, India Jörg Löwe  Lubinus Clinicum, Kiel, Germany Victor  Lu School of Clinical Medicine, University of Cambridge, Cambridge, UK Manish  Mahajan  Department of Neurology, Agrim Institute Neurosciences, Artemis Hospital, Gurgaon, Bindapur, Haryana, India

of

Ramneek Mahajan  Orthopedics and Head Joint Reconstruction Unit, Max Smart Super Speciality Hospital, Saket, New Delhi, India Vivek Mahajan  Indian Spinal Injuries Center (ISIC), New Delhi, India Lalit Maini  Department of Orthopaedics, Maulana Azad Medical College and LNJP Hospital, Delhi, India Rajesh Malhotra  Department of Orthopedics, All India Institute of Medical Sciences (AIIMS), New Delhi, India S. K. S. Marya  Max Institute of Musculoskeletal Sciences, Max Hospital Saket, Gurugram, India Max Institute of Musculoskeletal Sciences, Max Hospital Saket & Gurugram, New Delhi, Delhi, India Max Institute of Musculoskeletal Sciences, Max Hospital Saket & Gurugram, Gurugram, Haryana, India A.  B.  Suhas  Masilamani Sunshine Bone and Joint Institute, Sunshine Hospitals, Hyderabad, India Ed Massa  King’s College Hospital, London, UK Gregory  Minutillo Pennsylvania Hospital, University of Pennsylvania, Philadelphia, PA, USA Shubhranshu  S.  Mohanty King Edward Memorial Hospital, Mumbai, India Praharsha Mulpur  Sunshine Bone and Joint Institute, Sunshine Hospitals, Hyderabad, Telangana, India

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Alex Muttathupadam  Asian Orthopaedic Institute, Chennai, India Piyush Nashikkar  Max Smart Super Speciality Hospital, Saket, New Delhi, India Rajkumar  Natesan  Department of Orthopaedic Surgery, Ganga Hospital, Coimbatore, Tamil Nadu, India Mayur  Nayak Department of Orthopaedics, Guys and St Thomas NHS Trust, London, UK I. P. S. Oberoi  Joint Replacement and Sports injury Unit, Artemis Hospital, Gurgaon, Haryana, India Anil Thomas Oommen  Professor, Head, Orthopaedics, Christian Medical College, Vellore, Tamil Nadu, India Dhanasekararaja Palanisami  Department of Orthopaedic Surgery, Ganga Hospital, Coimbatore, Tamil Nadu, India Sameer Panchal  Department of Orthopaedics, Grant Medical College and Sir JJ Group of Hospital, Mumbai, India Phonthakorn  Panichkul Bangkok Hip and Knee Center, Bangkok International Hospital, Bangkok, Thailand Frederic Picard  Golden Jubilee National Hospital, Glasgow, UK Kevin Pirruccio  Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA Bodo Purbach  Wrightington Hospital, Wigan, UK Alok Rai  Department of Orthopedics, All India Institute of Medical Sciences (AIIMS), New Delhi, India N.  Rajkumar Department of Arthroplasty, Ganga Medical Center and Hospital, Coimbatore, India Rajeev Raman  Orthopedic Surgeon, Joint and Bone Care Hospital, Kolkata, India Rohit  Rambani Department of Orthopaedics, United Lincolnshire NHS Trust, Boston, Lincolnshire, UK Amar S. Ranawat  Hospital for Special Surgery, New York, NY, USA Clinical Orthopedic Surgery, Weill Cornell Medical College, New York, NY, USA NewYork-Presbyterian Hospital, New York, NY, USA A. V. Gurava Reddy  Sunshine Bone and Joint Institute, Sunshine Hospitals, Hyderabad, Telangana, India Jose A. Rodriguez  Hospital for Special Surgery, New York, NY, USA Weill Cornell Medical College, New York, NY, USA

Editor and Contributors

Editor and Contributors

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Samuel Rodriguez  Hospital for Special Surgery, New York, NY, USA K. H. Sancheti  Sancheti Institute for Orthopaedics and Rehabilitation, Pune, India Sahil  Sanghavi Sancheti Institute for Orthopaedics and Rehabilitation, Pune, India Indrajeet  Sardar Orthopaedics, Nightingale Hospital, Kolkatta, West Bengal, India Ramesh  K.  Sen  Institute of Orthopedics, Max Hospital, Mohali, Mohali, India Nikhil Shah  Centre for Hip Surgery, Wrightington Hospital, UK Wrightington Hospital, Wigan, UK Rajasekaran  Shanmuganathan Department of Orthopaedic Surgery, Ganga Hospital, Coimbatore, Tamil Nadu, India Mrinal  Sharma HOD ORTHOPEDICS & JOINT REPLACEMENT, Amrita Institute of Medical Sciences, Amrita Vishwavidyapeetham, Amrita School of Medicine, Faridabad, Delhi NCR, India Neil  P.  Sheth Pennsylvania Hospital, University of Pennsylvania, Philadelphia, PA, USA Avtar Singh  Amandeep Hospital, Amritsar, India Chandeep Singh  Max Institute of Musculoskeletal Sciences, Max Hospital Saket, New Delhi, Delhi, India Max Institute of Musculoskeletal Sciences, Max Hospital Gurugram, Gurugram, Haryana, India Parminder J. Singh  Maroondah Hospital, Melbourne, VIC, Australia Monash University, Hip Arthroscopy Australia, Melbourne, Australia Satvir Singh  Joint Replacement and Sports injury Unit, Artemis Hospital, Gurgaon, Haryana, India Chandrashekhar Sahebrao Sonawane  Department of Joint Replacement and Reconstruction, Deenanath Mangeshkar Hospital and Research Center, Pune, India Chetan  Sood Department Orthopaedics, Armed Forces Medical College, Pune, Maharashtra, India D. Soundarrajan  Department of Arthroplasty, Ganga Medical Center and Hospital, Coimbatore, India Kamolsak  Sukhonthamarn Department of Orthopaedics, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand Pichai  Suryanarayan Hip, Knee & Shoulder Surgery, Asian Orthopedic Institute, SIMS Hospitals, Chennai, Tamil Nadu, India

Editor and Contributors

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Asian Orthopedic Institute, AOI @ SIMS Hospitals, Chennai, Tamil Nadu, India Kanokpol  Tanakritrungtawee Bangkok Hip and Knee Center, Bangkok International Hospital, Bangkok, Thailand Babaji Sitaram Thorat  Amandeep Hospital, Amritsar, India Anjali Tiwari  Sir H.N. Reliance-Foundation Hospital and Research Centre, Mumbai, Maharashtra, India Sianne E. T. Toemoe  Maroondah Hospital, Melbourne, VIC, Australia Sujit  Kumar  Tripathy  Department of Orthopedics, AIIMS Bhubaneswar, Bhubaneswar, India Milkias  Tsehaye Department of Orthopedic Surgery, St. Paul’s Hospital Millennium Medical College, Addis Ababa, Ethiopia Narendra V. Vaidya  Lokmanya Group of Hospitals, Pune, India Abhishek Vaish  Indraprastha Apollo Hospitals, New Delhi, India Raju Vaishya  Indraprastha Apollo Hospitals, New Delhi, India Brian  Velasco Pennsylvania Hospital, University of Pennsylvania, Philadelphia, PA, USA Rajeev Vohra  Amandeep Hospital, Amritsar, India Caesar Wek  King’s College Hospital, London, UK Warran Wignadasan  University College London Hospitals, London, UK Chandra  Shekhar  Yadav  Joint Replacement Superspeciality Hospital, New Delhi, India

Department,

Jason Zlotnicki  Hospital for Special Surgery, New York, NY, USA

Primus

Part I Primary Total Hip Arthroplasty

1

Hip Biomechanics and Preoperative Assessment in Total Hip Arthroplasty Lalit Maini

1.1 Introduction Biomechanics is a scientific field concerned with the coordination of muscles, bones, tendons, and ligaments for the movement of the human body. The hip joint plays a crucial role in movement and weight-bearing, underscoring its importance in any activity. Understanding the anatomy and biomechanics of the hip joint is essential for diagnosing and treating various pathological conditions, particularly for the success of total hip replacement. An arthroplasty surgeon should have knowledge of the normal range of motion of the hip joint during daily activities. For example, tying a shoelace in a standing position requires 120–130 degrees of hip flexion, 20 degrees of external rotation, and 15–20 degrees of abduction. Ascending stairs require 70–75 degrees of flexion while descending stairs require 30–35 degrees of flexion at the hip joint [1, 2].

1.2 Kinematics and Kinetics Kinematics is concerned with the movement of the hip joint during functional activities, which is typically measured using opto-electric camera systems. On the other hand, kinetics involves the study of the forces and movements acting on the L. Maini (*) Department of Orthopaedics, Maulana Azad Medical College and LNJP Hospital, Delhi, India

joint to create motion, including gravitational forces, muscle contraction, and passive tension from the supporting ligaments. Joint reaction forces refer to the forces generated within the joint in response to external forces acting on the joint, and in the hip joint, these forces are necessary to balance the moment arms of body weight and abductor tension arm to keep the pelvis level. The human body is a well-engineered structure where bones and soft tissues interact in both static and dynamic ways to maintain balance and generate movement. Hip contact forces are a combination of ground reaction force, body weight, and abductor muscle contraction forces. These resultant hip reaction forces can be calculated either in  vivo by using strained-gauged prostheses or by using analytical approaches, such as two or three-dimensional models. Estimates of the hip joint using two-­ dimensional free-body diagrams are shown in Fig. 1.1. In a simplified two-dimensional model, the center of gravity of the body when standing on both legs is located between the two hips passing through the pubic symphysis, and its force is exerted equally on both hips. The weight of the body minus the weight of both legs is supported equally on the femoral heads, and the resultant vectors are vertical, making the pelvis stable and balanced in this position. During a single-legged stance, five-sixths of the body weight (one-sixth of the body weight of the ipsilateral lower limb is subtracted from body

© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_1

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L. Maini

muscles. Therefore, the abductor muscles must generate a force of approximately twice the body weight to maintain the pelvis in balanced equilibrium during a single-limb stance. The lever arm ratio of the hip abductor muscle force to the gravitational force is a major influence on the joint reaction force of the hip joint. Abductor muscle force × Abductor lever arm ( a ) = Body weight ( W ) × Body weight lever arm ( b )



Abductor muscle force ( M ) = W × ( b / a ) Joint reaction force = Body weight ( W ) + Abductor muscle force ( M )

Fig. 1.1  The blue line shows gravitational force; the red line shows the line connecting the center of femoral heads

Fig. 1.2  Free body diagram showing the vectors of abductor muscle force and body weight force along the moment arm

weight) is applied to the hip joint, and its vector is vertical. To achieve equilibrium in this position, the moment of abductor muscle force acting upon the joint must balance the moment produced by gravitational force. The abductor ­muscle force is oriented medially and superiorly at an angle of 30° from the vertical line. The abductor muscle force multiplied by its lever arm must be equal to the body weight force multiplied by its lever arm to keep a balanced pelvis (Fig. 1.2). The abductor muscle moment arm is roughly half the length of the moment arm of the gravitational force, giving a 2:1 mechanical advantage to the force of body weight over the abductor

The magnitude of resultant hip joint contact forces is influenced by various parameters. Among these, the abductor lever arm and the body-weight lever arm are two predictors that can be easily modified during hip replacement surgery from a mechanical perspective. Increasing the abductor moment arm can reduce the ratio (b/a) and subsequently lessen the reaction force exerted by the femoral head on the acetabulum. This is why Charnley proposed detaching the greater trochanter and reattaching it in a lateral location (lateralization of the greater trochanter). Similarly, by medializing the new center of the joint, the body-weight lever arm can be decreased, resulting in a reduction of the ratio and ultimately joint reaction force (medialization of the hip). Conversely, a wider pelvis increases the body-­ weight lever arm, leading to increased joint reaction forces during a single-legged stance. It is important to understand these mechanics when studying hip diseases that may affect the length of the muscle moment arms. If the moment arms shorten, the muscle force must increase to achieve the same moment. When there is a significant change in hip joint mechanics, the patient may need to use compensatory strategies to maintain balance. In cases where hip joint arthritis causes pain, reducing the joint reaction force can help alleviate the pain. This can be accomplished by reducing the body weight moment arm (b) by leaning toward the

1  Hip Biomechanics and Preoperative Assessment in Total Hip Arthroplasty

painful side. Alternatively, the patient can use a walking stick on the opposite side to reduce the hip abductor force and thereby decrease the joint reaction force and alleviate pain in the affected hip. Abductor muscle force = ( Body weight ( W ) × b / c )



 Walking stick    force × c / a 

−

The abductor mechanism is clinically significant as weakness in this area can cause the pelvis to drop toward the non-weight bearing side during the stance phase of gait, known as the Trendelenburg gait. Similarly, a drop of the pelvis towards the opposite side during a single limb stance is called a positive Trendelenburg sign.

1.3 Biomechanics of Total Hip Arthroplasty The stability and range of motion of a total hip arthroplasty depend on the cup positioning, the size of the head, and the femoral stem.

5

hip abductor muscle. For example, a superomedial placed cup can decrease this capacity by up to 65%. Increasing the prosthetic neck length can restore this capacity for the superior and superomedial placed cups but not for the superolateral placed cup. The orientation of the acetabular component also affects stem-cup impingement and dislocation [4, 5]. Cup inclination and anteversion are critical factors to consider. Decreasing the inclination of the acetabular component results in a more horizontal position and antero-superior weight bearing area but decreased postero-­ inferior coverage. Increasing the cup anteversion has the opposite effect, reducing the anterosuperior weight bearing area and increasing the posteroinferior coverage [6].

1.3.2 The Femoral Component The femoral neck’s three anatomical features that influence hip biomechanics are as follows:

1.3.1 Acetabular Cup Positioning

• Femoral neck anteversion • Femoral offset • Head-neck ratio

Finding the optimal position for the acetabular cup during a total hip arthroplasty can be challenging. This includes determining the best medio-lateral position, supero-inferior position, inclination, and version of the cup. The position of the cup can significantly impact the moment-­ generating capacity of the hip abductor muscles. If the cup is medially displaced, it allows for a larger femoral offset and reduces joint loading and wear. On the other hand, lateral displacement decreases the femoral offset, increases joint reaction forces, and ultimately causes more wear. Superior placement of the acetabular cup decreases abduction and flexion forces, moments, and moment arms for flexion and abduction. Conversely, inferior placement increases forces, moments, and moment arms [3]. Combining superior and lateral or medial deviation further impacts the moment-generating capacity of the

Restoring these features to their pre-disease status is essential for the successful function of a hip arthroplasty (Fig. 1.3). The femoral offset is the distance between the center of rotation of the femoral head and the longitudinal axis of the femur. A decrease in offset has been linked to increased hip joint reaction forces, while a larger femoral offset produces a greater abductor lever arm, which reduces hip joint reaction forces and decreases the wear of the polyethylene component. Maintaining an appropriate femoral offset is also important for controlling soft tissue tension, improving overall function, and increasing abductor muscle strength. However, an excessive offset can cause micro motion at the implant–bone interface, leading to stress fractures or dislocation, and overly tight ligament tension can negatively affect joint lubrication and increase wear [7, 8].

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Fig. 1.3  Features of femoral component. Neck length is measured from the center of the femur head to the base of the collar. The head stem offset measured from the center of the head to the line through the axis of the distal part of the stem

Femoral neck anteversion refers to the forward rotation of the femoral neck relative to the anatomical axis of the femoral shaft. This rotation allows for an increased range of flexion and internal rotation before the femoral neck comes into contact with the acetabular rim. Anteversion not only enhances the range of motion but also causes the greater trochanter to move posteriorly and decreases the femoral offset [9]. The head-neck ratio, which is the difference in circumference between the femoral head and the femoral neck, allows for movement within the joint before the neck impinges on the acetabular rim.

1.3.3 Position of Stem The position of the stem also affects the biomechanics of the hip joint and the forces transmitted through the implant. A valgus stem position increases lateral offset and decreases medial offset, thereby reducing hip joint reaction forces and the risk of dislocation. On the other hand, a varus stem position increases medial offset and

L. Maini

Fig. 1.4  Diagram showing the valgus stem positioning increases the axial loading of the stem and shortens the abductor lever arm

decreases lateral offset, leading to higher hip joint reaction forces and a greater likelihood of dislocation. Proper alignment of the stem is critical to ensure optimal function and longevity of the implant, and it must be tailored to the individual patient’s anatomy. Valgus Stem  Positioning of the stem in the valgus produces the following changes (Fig. 1.4): • • • • •

Decreases the moment of bending Increases axial loading of stem Shortens the abductor lever arm Results in valgus strain on knee Lengthens the limb

Varus Stem  Positioning the stem in the varus has the following effects: • • • •

Increases moment of bending Decreases axial loading of stem Lengthens the abductor lever arm Shortens the limb

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1  Hip Biomechanics and Preoperative Assessment in Total Hip Arthroplasty

1.3.4 Size of Head Head size directly influences the range of motion (Fig. 1.5). Increasing the size of the femoral head can lead to an increase in the range of motion (Fig. 1.6) as well as the distance the head must travel before dislocating from the cup (known as the jumping distance), which is typically around

50% of the head diameter in hemispherical cups (as shown in Fig. 1.7). However, this benefit is offset by higher friction moments that must be supported by the fixation of the bearing components, resulting in a higher wear rate for larger heads [10, 11]. Another disadvantage of larger heads is that they require a greater degree of joint separation to relocate the head into the acetabulum.

Fig. 1.5 Increasing head size increases the range of motion at the hip

90º

106º

22 mm

32 mm

Fig. 1.6  Increased head size increases the Jump Distance and stability

B A A36  mm) do not provide any significant additional benefit in terms of ROM [84–87]. In fact, femoral head size of 32 mm is sufficient to have an adequate range of motion for activities of daily living.

15.5.2 Dislocation Larger head size reduces the incidence of dislocation by increasing the jump distance. The registry data from Australia showed that the incidence of dislocation decreases by increasing the head size.

R. Malhotra et al.

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With ceramic-on-ceramic bearing, the dislocation rate with ≤28  mm, 32  mm, 36/38  mm, and ≥ 40 mm heads was 1.8%, 0.4%, 0.3%, and 0.2% respectively [88]. Shah et al. reported no difference in risk of revision for dislocation when compared among metal-on-­polyethylene, ceramicon-polyethylene, and ceramic-on-ceramic bearings for 28 mm and 32 mm heads [89].

15.5.3 Wear Characteristics It was believed that larger femoral heads are more prone to volumetric wear. However, the available literature is contrasting on it. Deckard et al. and Lachiewicz et al. in their independent studies reported that the volumetric head penetration for 32 mm head is lower than the larger heads [90, 91]. In contrast, the studies by Hammerberg et al. and Stambough et al. found no significant difference in the linear wear and volumetric wear between 28/32  mm and 38/44  mm, and 28  mm and 32  mm heads, respectively [85, 92].

15.5.4 Taper Corrosion Larger heads are more prone to greater corrosion and fretting due to greater torque along the taper interface [93]. However, there are also studies reporting no association between increased head and taper corrosion [94, 95]. Nevertheless, if any material loss occurs from the head–stem junction, it is less from a ceramic head than a metallic head. Hence, a ceramic larger head is less prone to corrosion than a metallic larger head. Hence, the authors conclusion regarding head size is that a 32 mm head is sufficient enough to provide stability and ROM with minimum wear. However, the size may have to be changed according to the cup size.

15.6 Summary With a number of prostheses for primary THA available on the market, it is often difficult to choose between them, especially for the newer

joint replacement surgeons. It is imperative to have a better understanding of the rationale behind each design scientifically and match it with the current evidence. The most important factors while choosing a particular implant design are patient’s age, quality of the bone, proximal femoral anatomy, and functional demand. Affordability of the patient also becomes an important factor when the patient has to bear the cost of the implant themselves. Age-wise, THA implants combination in elderly patients should be selected in a such a way that apart from relieving pain and improving the function, it should last for the rest of patient’s life. While in younger patients, the implants should be fixed with minimum bone resection, should lose minimal bone while extraction, and allow easy revision in future.

References 1. Liang MH, Cullen KE, Poss R. Primary total hip or knee replacement: evaluation of patients. Ann Intern Med. 1982;97(5):735–9. 2. Sochart DH, Porter ML.  Long-term results of cemented Charnley low-friction arthroplasty in patients aged less than 30  years. J Arthroplast. 1998;13(2):123–31. 3. Callaghan JJ, Forest EE, Olejniczak JP, et al. Charnley total hip arthroplasty in patients less than fifty years old. A twenty to twenty-five-year follow-up note. J Bone Joint Surg Am. 1998;80(5):704–14. 4. Malchau H, Garellick G, Eisler T, Karrholm J, Herberts P.  Presidential guest address: the Swedish hip registry: increasing the sensitivity by patient outcome data. Clin Orthop Relat Res. 2005;441:19. 5. McMinn DJ, Snell KI, Daniel J, Treacy RB, Pynsent PB, Riley RD.  Mortality and implant revision rates of hip arthroplasty in patients with osteoarthritis: registry based cohort study. Br Med J. 2012;344:e3319. 6. Smith MA, Smith WT.  The American joint replacement registry. Orthop Nurs. 2012;31(5):296. 7. Jameson SS, Kyle J, Baker PN, Mason J, Deehan DJ, McMurtry IA, et al. Patient and implant survival following 4323 total hip replacements for acute femoral neck fracture: a retrospective cohort study using National Joint Registry data. J Bone Joint Surg (Br). 2012;94(11):1557. 8. Ranawat CS, Peters LE, Umlas ME.  Fixation of the acetabular component the case for cement. Clin Orthop Relat Res. 1997;344:207–15. 9. Gaffey JL, Callaghan JJ, Pedersen DR, et  al. Cementless acetabular fixation at fifteen years a comparison with the same surgeon's results following acetabular fixation with cement. J Bone Joint Surg Am. 2004;86:257–61.

15  Implant Selection and Rationale for Use in Primary Total Hip Arthroplasty 10. Ritter MA, Thong AE. The role of cemented sockets in 2004: is there one? J Arthroplast. 2004;19:92–4. 11. Trumm BN, Callaghan JJ, Liu SS, Goetz DD, Johnston RC.  Revision with cementless acetabular components: a concise follow-up, at a minimum of twenty years, of previous reports. J Bone Joint Surg Am. 2012;94(21):2001–4. https://doi.org/10.2106/ JBJS.L.00058. 12. Otten V, Mukka S, Nilsson K, Crnalic S, Kärrholm J.  Uncemented cups with and without screw holes in primary THA: a Swedish hip arthroplasty register study with 22,725 hips. Acta Orthop. 2019;90(3):258– 63. https://doi.org/10.1080/17453674.2019.1599777. 13. Flivik G, Kristiansson I, Kesteris U, Ryd L. Is removal of subchondral bone plate advantageous in cemented cup fixation? A randomized RSA study. Clin Orthop Relat Res. 2006;448:164. 14. Corten K, Au K, Bourne RB. Acetabular options: notes from the other side. Orthopedics. 2009;32(9):664. ;orthosupersite.com/view.asp?rID=42834. https://doi. org/10.3928/01477447-­20090728-­10. 15. Lampropoulou-Adamidou K, Hartofilakidis G. Comparison of the long-term outcome of cemented Charnley low-friction arthroplasty with hybrid arthroplasty in patients with congenital hip disease. Bone Joint J. 2019;101-B(9):1050–7. https://doi. org/10.1302/0301-­620X.101B9.BJJ-­2018-­1208.R1. 16. Okutani Y, Goto K, Kuroda Y, Kawai T, Okuzu Y, Kawata T, Shimizu Y, Matsuda S. Long-term outcome of cemented total hip arthroplasty with the Charnley-­ type femoral stem made of titanium alloy. J Orthop Sci. 2019;24(6):1047–52. https://doi.org/10.1016/j. jos.2019.07.013. 17. Schmitz MW, Busch VJ, Gardeniers JW, Hendriks JC, Veth RP, Schreurs BW.  Long-term results of cemented total hip arthroplasty in patients younger than 30 years and the outcome of subsequent revisions. BMC Musculoskelet Disord. 2013;14:37. https://doi.org/10.1186/1471-­2474-­14-­37. 18. Hirose S, Otsuka H, Morishima T, Sato K. Outcomes of Charnley total hip arthroplasty using improved cementing with so-called second- and third-­generation techniques. J Orthop Sci. 2012;17(2):118–23. https:// doi.org/10.1007/s00776-­011-­0180-­x. 19. Carter DR, Vasu R, Harris WH. Stress distribution in the acetabular region 2. Effects of cement thickness and metal backing of total hip acetabular component. J Biomech. 1982;1982(15):165–70. 20. Carter DR. Finite-element analysis of a metal-backed acetabular component. In: The Hip; Proceedings of the Eleventh Open Scientific Meeting of the Hip Society. St Louis: Mosby; 1983. p. 216–28. 21. Dalstra M, Huskies R. The influence of metal backing in cemented cups. Orthop Trans. 1991;16:272–5. 22. Harris WH, Penenberg BL.  Further follow-up on socket fixation using a metal-backed acetabular component for Total hip replacement. J Bone Joint Surg. 1987;69-A(8):1140–3. 23. Chen FS, Di Cesare PE, Kale AA, Lee JF, Frankel VH, Stuchin SA, Zuckerman JD.  Results of cemented metal-backed acetabular components:

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a 10-year-­ average follow-up study. J Arthroplast. 1998;13(8):867–73. https://doi.org/10.1016/ s0883-­5403(98)90191-­7. 24. Mohan R, Grigoris P, Johnstone F, Hamblen D.  Howse II cemented titanium metal-backed acetabular cups poor 10-year results in 107 hips. Acta Orthop Scand. 2003;74(4):397–403. https://doi. org/10.1080/00016470310017686. 25. Weiss RJ, Hailer NP, Stark A, Kärrholm J. Survival of uncemented acetabular monoblock cups: evaluation of 210 hips in the Swedish hip arthroplasty register. Acta Orthop. 2012;83(3):214–9. https://doi.org/10.31 09/17453674.2012.688726. 26. Zhao CC, Qu GX, Yan SG, et al. Squeaking in fourth-­ generation ceramic-on-ceramic total hip replacement and the relationship with prosthesis brands: meta-analysis and systematic review. J Orthop Surg Res. 2018;13:133. https://doi.org/10.1186/ s13018-­018-­0841-­y. 27. Yamada H, Yoshihara Y, Henmi O, Morita M, Shiromoto Y, et  al. Cementless total hip ­replacement: past, present, and future. J Orthop Sci. 2009;14:228–41. 28. Jarcho M, Kay JF, Gumaer KI, Doremus RH, Drobeck HP.  Tissue, cellular and subcellular events at a bone-ceramic hydroxyapatite Interface. J Bioeng. 1977;1(2):79–92. 29. Ducheyne P, Hench L, Kagan A, Martens M, Bursens A, Mulier J. Effect of hydroxyapatite impregnation on skeletal bonding of porous coated implants. J Biomed Mater Res. 1980;14(3):225–37. 30. Moilanen T, Stocks GW, Freeman MA, Scott G, Goodier WD, Evans SJ. Hydroxyapatite coating of an acetabular prosthesis. Effect on stability. J Bone Joint Surg (Br). 1996;78:200–5. 31. Roffman M, Kligman M.  Cementless coated and noncoated Mathys acetabular cups: radiographic and histologic evaluation. Orthopedics. 1999;22:39–41. 32. Ali MS, Kumar A. Hydroxyapatite-coated RM cup in primary hip arthroplasty. Int Orthop. 2003;27:90–3. 33. Reikeras O, Gunderson RB. Failure of HA coating on a gritblasted acetabular cup: 155 patients followed for 7-10 years. Acta Orthop Scand. 2002;73:104–8. 34. Lai KA, Shen WJ, Chen CH, Yang CY, Hu WP, Chang GL. Failure of hydroxyapatite-coated acetabular cups. Ten-year follow-up of 85 Landos atoll arthroplasties. J Bone Joint Surg (Br). 2002;84:641–6. 35. Miyakawa S, Kawamura H, Mishima H, Yasumoto J.  Grit-blasted and hydroxyapatite-coated total hip arthroplasty: an 11- to 14-year follow-up study. J Orthop Sci. 2004;9:462–7. 36. Cheung KW, Yung SH, Wong KC, Chiu KH.  Early failure of smooth hydroxyapatite-coated press-fit acetabular cup–7 years of follow-up. J Arthroplast. 2005;20:627–31. 37. Kim SY, Kim DH, Kim YG, Oh CW, Ihn JC.  Early failure of hemispheric hydroxyapatite-coated acetabular cups. Clin Orthop. 2006;446:233–8. 38. Morscher EW, Hefti A, Aebi U.  Severe osteolysis after third-body wear due to hydroxyapatite particles

214 from acetabular cup coating. J Bone Joint Surg (Br). 1998;80:267–72. 39. Lazarinis S, Kärrholm J, Hailer NP.  Increased risk of revision of acetabular cups coated with hydroxyapatite. Acta Orthop. 2010;81(1):53–9. https://doi. org/10.3109/17453670903413178. 40. Havelin LI, Espehaug B, Engesaeter LB.  The performance of two hydroxyapatite-coated acetabular cups compared with Charnley cups. From the Norwegian arthroplasty register. J Bone Joint Surg (Br). 2002;84(6):839–45. https://doi. org/10.1302/0301-­620x.84b6.12492. 41. Lazarinis S, Mäkelä KT, Eskelinen A, Havelin L, Hallan G, Overgaard S, Pedersen AB, Kärrholm J, Hailer NP.  Does hydroxyapatite coating of uncemented cups improve long-term survival? An analysis of 28,605 primary total hip arthroplasty procedures from the Nordic arthroplasty register association (NARA). Osteoarthr Cartil. 2017;25(12):1980–7. https://doi.org/10.1016/j.joca.2017.08.001. 42. Gottliebsen M, Rahbek O, Ottosen PF, Søballe K, Stilling M. Superior 11-year survival but higher polyethylene wear of hydroxyapatite-coated Mallory-­ head cups. Hip Int. 2012;22(1):35–40. https://doi. org/10.5301/HIP.2012.9075. 43. Laursen MB, Nielsen PT, Søballe K.  Bone remodelling around HA-coated acetabular cups: a DEXA study with a 3-year follow-up in a randomised trial. Int Orthop. 2007;31(2):199–204. https://doi.org/10.1007/ s00264-­006-­0148-­1. 44. Bobyn JD, Stackpool GJ, Hacking SA, Tanzer M, Krygier JJ.  Characteristics of bone ingrowth and interface mechanics of a new porous tantalum biomaterial. J Bone Joint Surg (Br). 1999;81(5):907–14. 45. Lachiewicz PF, Soileau ES. Second-generation modular acetabular components provide fixation at 10 to 16 years. Clin Orthop Relat Res. 2012;470(2):366–72. https://doi.org/10.1007/s11999-­011-­1950-­7. 46. Valle AG, Zoppi A, Peterson MG, Salvati EA.  Clinical and radiographic results associated with a modern, cementless modular cup design in total hip arthroplasty. J Bone Joint Surg Am. 2004;86(9):1998–2004. https://doi. org/10.2106/00004623-­200409000-­00019. 47. Kim JT, Yoo JJ.  Implant design in cementless hip arthroplasty. Hip Pelvis. 2016;28(2):65–75. https:// doi.org/10.5371/hp.2016.28.2.65. 48. Malhotra R, Gautam D.  Acute total hip arthroplasty in acetabular fractures using modern porous metal cup. J Orthop Surg (Hong Kong). 2019;27(2):2309499019855438. https://doi. org/10.1177/2309499019855438. 49. Antoniades G, Smith EJ, Deakin AH, Wearing SC, Sarungi M.  Primary stability of two uncemented acetabular components of different geometry: hemispherical or peripherally enhanced? Bone Joint Res. 2013;2(12):264–9. https://doi. org/10.1302/2046-­3758.212.2000193.

R. Malhotra et al. 50. Langlais FL, Ropars M, Gaucher F, Musset T, Chaix O.  Dual mobility cemented cups have low dislocation rates in THA revisions. Clin Orthop Relat Res. 2008;466:389–95. 51. Epinette JA, Béracassat R, Tracol P, Pagazani G, Vandenbussche E.  Are modern dual mobility cups a valuable option in reducing instability after primary hip arthroplasty, even in younger patients? J Arthroplast. 2014;29(6):1323–8. https://doi. org/10.1016/j.arth.2013.12.011. 52. Blakeney WG, Epinette JA, Vendittoli PA.  Dual mobility total hip arthroplasty: should everyone get one? EFORT Open Rev. 2019;4(9):541–7. https://doi. org/10.1302/2058-­5241.4.180045. 53. Stulberg SD.  Dual poly liner mobility optimizes wear and stability in THA: affirms. Orthopedics. 2011;34:e445–8. 54. Wyatt M, Hooper G, Frampton C, Rothwell A. Survival outcomes of cemented compared to uncemented stems in primary total hip replacement. World J Orthop. 2014;5:591–6. 55. Blankstein M, Lentine B, Nelms NJ.  The use of cement in hip arthroplasty: a contemporary perspective. J Am Acad Orthop Surg. 2020;28(14):e586–94. https://doi.org/10.5435/JAAOS-­D-­19-­00604. 56. Rivière C, Grappiolo G, Engh CA Jr, et al. Long-term bone remodelling around 'legendary' cementless femoral stems. EFORT Open Rev. 2018;3:45–57. https:// doi.org/10.1302/2058-­5241.3.170024. 57. Swedish National hip Arthroplasty Register Annual Report 2007. Sahlgrenska University Hospital, Goteburg; 2008. 58. Norwegian Arthroplasty Register. Haukeland University Hospital; 2008. 59. Carrington NC, Sierra RJ, Gie GA, Hubble MJ, Timperley AJ, Howell JR.  The Exeter universal cemented femoral component at 15 to 17 years: an update on the first 325 hips. J Bone Joint Surg (Br). 2009;91:730–7. 60. Espehaug B, Furnes O, Engesaeter LB, Havelin LI. 18 years of results with cemented primary hip prostheses in the Norwegian arthroplasty register. Acta Orthop. 2009;80:402–12. 61. Ling RS, Charity J, Lee AJ, Whitehouse SL, Timperley AJ, Gie GA.  The long-term results of the original Exe- ter polished cemented femoral component: a follow-up report. J Arthroplast. 2009;24:511–7. 62. Wroblewski BM, Siney PD, Fleming PA.  Charnley low-frictional torque arthroplasty: follow-up for 30 to 40 years. J Bone Joint Surg (Br). 2009;91–4:447–50. 63. Fowler JL, Gie GA, Lee AJ, Ling RS.  Experience with the Exeter total hip replacement since 1970. Orthop Clin North Am. 1988;19:477–89. 64. Ling RS.  The use of a collar and precoating on cemented femoral stems is unnecessary and detrimental. Clin Orthop Relat Res. 1992;285:73–83. 65. Verdonschot N, Huiskes R.  Surface roughness of debonded straight-tapered stems in cemented

15  Implant Selection and Rationale for Use in Primary Total Hip Arthroplasty THA reduces subsidence but not cement damage. Biomaterials. 1998;19:1773–9. 66. Schmitz MW, Busch VJ, Gardeniers JW, et al. Long-­ term results of cemented total hip arthroplasty in patients younger than 30 years and the outcome of subsequent revisions. BMC Musculoskelet Disord. 2013;14:37. 67. Berry D.  Evolution of uncemented femoral component design. In: Pellicci PM, Tria AJ, Garvin KL, editors. Orthopaedic knowledge update: hip and knee recon- struction 2. 2nd ed. Rosemont: American Academy of Orthopaedic Surgeons; 2000. 68. Khanuja HS, Vakil JJ, Goddard MS, Mont MA. Cementless femoral fixation in total hip arthroplasty. J Bone Joint Surg Am. 2011;93(5):500–9. 69. Khanuja HS, Banerjee S, Jain D, Pivec R, Mont MA.  Short bone-conserving stems in cementless hip arthroplasty. J Bone Joint Surg Am. 2014;96(20):1742–52. 70. Kheir MM, Drayer NJ, Chen AF.  An update on Cementless femoral fixation in Total hip arthroplasty. J Bone Joint Surg. 2020;102(18):1646–61. https://doi. org/10.2106/jbjs.19.01397. 71. Morshed S, Bozic KJ, Ries MD, Malchau H, Colford JM.  Comparison of cemented and uncemented fixation in total hip replacement: a meta-analysis. Acta Orthop. 2007;78(3):315–26. 72. Eskelinen A, Remes V, Helenius I, et  al. Total hip arthroplasty for primary osteoarthrosis in younger patients in the Finnish arthroplasty register. 4,661 primary replacements followed for 0–22 years. Acta Orthop. 2005;76(1):28–41. 73. Mäkelä KT, Eskelinen A, Pulkkinen P, Paavolainen P, Remes V. Results of 3,668 primary total hip replacements for primary osteoarthritis in patients under the age of 55 years. Acta Orthop. 2011;82:521–9. 74. Sands D, Schemitsch EH. The role of metal-on-metal bearings in total hip arthroplasty and hip resurfacing: review article. HSS J. 2017;13(1):2–6. https://doi. org/10.1007/s11420-­016-­9521-­9. 75. Ahmad A, Mirza Y, Evans AR, Teoh KH.  A comparative study between un- cemented and hybrid total hip arthroplasty in octogenarians. J Arthroplast. 2018;33(12):3719–23. 76. Riley SA, Spears JR, Smith LS, Mont MA, Elmallah RK, Cherian JJ, Malkani AL.  Cementless tapered femoral stems for total hip arthroplasty in octogenarians. J Arthroplast. 2016;31(12):2810–3. 77. Stihsen C, Springer B, Nemecek E, Olischar B, Kaider A, Windhager R, Kubista B.  Cementless total hip arthroplasty in octogenarians. J Arthroplast. 2017;32(6):1923–9. 78. Abdel MP, Watts CD, Houdek MT, Lewallen DG, Berry DJ.  Epidemiology of periprosthetic fracture of the femur in 32 644 primary total hip arthroplasties: a 40-year experience. Bone Joint J. 2016;98-B(4):461–7.

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79. Gkagkalis G, Goetti P, Mai S, Meinecke I, Helmy N, Bosson D, Kutzner KP.  Cementless short-stem total hip arthroplasty in the elderly patient  - is it a safe option?: a prospective multicentre observational study. BMC Geriatr. 2019;19(1):112. 80. Bedard NA, Burnett RA, DeMik DE, Gao Y, Liu SS, Callaghan JJ.  Are Trends in total hip arthroplasty bearing surface continuing to change? 2007-­ 2015 usage in a large database cohort. J Arthroplast. 2017;32(12):3777–81. https://doi.org/10.1016/j. arth.2017.07.044. 81. Lindalen E, Thoen PS, Nordsletten L, Hovik RSM.  Low wear rate at 6-year follow-up of vitamin E-infused cross-linked polyethylene: a randomised trial using 32- and 36-mm heads. Hip Int. 2018;29(4):355–62. https://doi. org/10.1177/1120700018798790. 82. Australian Orthopedic Association. National Joint Registry. 2017. https://aoanjrr.sahmri.com/ annual-­reports-­2017. 83. Burroughs BR, Hallstrom B, Golladay GJ, Hoeffel D, Harris WH. Range of motion and stability in total hip arthroplasty with 28-, 32-, 38-, and 44-mm femoral head sizes. J Arthroplast. 2005;20(1):11–9. 84. Matsushita A, Nakashima Y, Jingushi S, Yamamoto T, Kuraoka A, Iwamoto Y. Effects of the femoral offset and the head size on the safe range of motion in total hip arthroplasty. J Arthroplast. 2009;24(4):646–51. 85. Hammerberg EM, Wan Z, Dastane M, Dorr LD. Wear and range of motion of different femoral head sizes. J Arthroplast. 2010;25(6):839–43. 86. Matsushita I, Morita Y, Ito Y, Gejo R, Kimura T. Activities of daily living after total hip arthroplasty. Is a 32-mm femoral head superior to a 26-mm head for improving daily activities? Int Orthop. 2011;35(1):25–9. 87. Delay C, Putman S, Dereudre G. Is there any range-­ of-­ motion advantage to using bearings larger than 36mm in primary hip arthroplasty: a case-control study comparing 36-mm and large-diameter heads. Orthop Traumatol Surg Res. 2016;102(6):735–40. 88. Hip knee and shoulder arthroplasty. 2018. Australian Orthopaedic Association National Joint Replacement Registry Annual. 89. Shah SM, Walter WL, Tai SM, Lorimer MF, de Steiger RN. Late dislocations after total hip arthroplasty: is the bearing a factor? J Arthroplast. 2017;32(9):2852–6. 90. Deckard ER, Meneghini RM. Femoral head penetration rates of second-generation sequentially annealed highly cross-linked polyethylene at minimum five years. J Arthroplast. 2019;34(4):781–8. 91. Lachiewicz PF, Heckman DS, Soileau ES, Mangla J, Martell JM. Femoral head size and wear of highly cross-linked polyethylene at 5 to 8 years. Clin Orthop Relat Res. 2009;467(12):3290–6. 92. Stambough JB, Pashos G, Wu N, Haynes JA, Martell JM, Clohisy JC.  Gender differences in wear rates for 28- vs 32-mm ceramic femoral heads on modern

216 highly cross-linked polyethylene at midterm follow­up in young patients undergoing total hip arthroplasty. J Arthroplast. 2016;31(4):899–905. 93. Dyrkacz RM, Brandt JM, Ojo OA, Turgeon TR, Wyss UP. The influence of head size on corrosion and fretting behaviour at the head-neck interface of artificial hip joints. J Arthroplast. 2013;28(6):1036–40. 94. Triantafyllopoulos GK, Elpers ME, Burket JC, Esposito CI, Padgett DE, Wright TM.  Otto aufranc

R. Malhotra et al. award: large heads do not increase damage at the head-­ neck taper of metal-on-polyethylene total hip arthroplasties. Clin Orthop Relat Res. 2016;474(2):330–8. 95. Cartner J, Aldinger P, Li C, Collins D. Characterization of femoral head taper corrosion features using a 22-year retrieval database. HSS J. 2017;13(1):35–41.

Part III Total Hip Arthroplasty in Complex Scenario

Total Hip Arthroplasty in Avascular Necrosis of Hip

16

Shitij Kacker and S. K. S. Marya

16.1 Introduction Avascular necrosis (AVN) or osteonecrosis is a condition characterized by disruption of osseous blood supply and impairment of cellular function, resulting in cell death, bone infarction, and ultimately joint degeneration. The incidence of AVN has been reported to be nearly 3 per 1,00,000 people. Hip is the most common joint to be affected by AVN with AVN accounting for nearly 10% of all the total hip arthroplasties (THAs) performed. The knee, shoulder, wrist, and ankle are other commonly affected joints and although rare sometimes multifocal osteonecrosis (affection of 3 or more joints) is also encountered in our day-to-day practice.

16.2 Causes of Avascular Necrosis of Hip Joint Several direct and indirect causes have been identified as risk factors for the development of avascular necrosis. Certain risk factors like trauma (leading to disruption of vascular supply as well direct damage to osteocytes), hemoglobinopathies like sickle cell disease (causing vascular occlusion), and radiation (cell death) have been identified as direct risk factors for the development of AVN. The pathophysiology of how indirect risk factors lead to development of AVN is poorly understood. It is widely believed that corticosteroids and alcohol intake leads to decreased mesenchymal activity and increased fat cells proliferation and hypertrophy, leading to an increase in intraosseous pressure (Table  16.1). Thus alcohol and steroid intake has been implicated as the most common indirect risk factors causing AVN where a direct causative agent has not been identified (Table 16.2).

S. Kacker · S. K. S. Marya (*) Max Institute of Musculoskeletal Sciences, Max Hospital, Saket, Gurugram, India © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_16

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S. Kacker and S. K. S. Marya

220 Table 16.1  Pathophysiology of development of AVN Atraumatic Pathway

Trauma ( Fracture/Dislocation)

Alcohol

Interruption of blood flow

Fat emboli

Steroids

Sickle cell

Drugs toxin radiation

Ischemia

Avascular necrosis of bone

Adipocytes hypertrophy, Cell death and vascular occlusion

Increase in intraosseous pressure Bone resorption & Collapse

Table 16.2  Risk factors for development of AVN Risk factors for developing Avascular Necrosis Direct causes Indirect causes Trauma Corticosteroid intake Hemoglobinopathies like Alcohol intake sickle cell disease Radiation Myeloproliferative disorders Chemotherapy Renal failure Genetic factors Autoimmune diseases Smoking Dysbaric phenomenon

16.3 Clinical Presentation Patients typically present with complaints of groin pain although a few patients may present with non-specific symptoms of trochanteric pain or buttock pain or pain in back with radiculitis. Sometimes, a patient may also present with referred pain in the ipsilateral knee which on

examination reveals that the real pathology is in the hips and not in the knees. Patient’s age, activity level, comorbidities, general health, and prior history of surgery should all be taken into consideration while proposing a treatment for the patient. Although clinical symptoms and radiological findings are the most important factors while deciding the appropriate treatment, these factors do play a major role in individualizing the treatment protocol. Radiologically similar lesions may be treated differently depending on the patients’ age, comorbidities, lifestyle demands, and activity level. The etiology of AVN should always be kept in mind as the presence of risk factors like renal failure, liver disease, chronic steroid intake can lead to postop complications like delayed wound healing or infection. While formulating a treatment protocol, the surgeon should keep in mind that AVN is often bilateral (incidence reported between 50% and 100%) (Fig. 16.1). While planning for joint preserving procedures like core decompression, it is

16  Total Hip Arthroplasty in Avascular Necrosis of Hip

Fig. 16.1  Bilateral AVN

usually advisable to perform the procedure on both sides. However, when contemplating an arthroplasty, it is advisable to perform it one hip at a time usually the more symptomatic hip should be dealt with first (Fig. 16.1).

16.4 Radiographic Evaluation X-ray and MRI are the mainstay in the evaluation of a patient who presents with groin pain and risk factors associated with AVN. The current ­protocol for diagnosis of AVN is prescribing plain AP and frog-leg lateral radiographs of the hip, followed by MRI. The AP radiograph usually demonstrates the primary area of involvement. Generally, subchondral cysts or sclerosis are visible on X-ray. The frog-leg lateral view is important as sometimes subtle sclerotic or cystic changes in the subchondral regions may be missed because of the overlap of the anterior and the posterior margins of the acetabulum on the superior surface of the femoral head. MRI is the gold standard for diagnosis and also for staging the disease. MRI has been reported to have a sensitivity and specificity of 99% for diagnosis of AVN. Other diagnostic modalities for diagnosing AVN include bone-marrow pressure measurement, venography, and core biopsy. Although these tests are sensitive as well as specific, they

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are invasive and are advisable only if plain radiography and MRI findings are negative in a patient who otherwise clinically gives a high suspicion of suffering with AVN. Similarly, CT scan is avoided in a patient of AVN due to risk of exposure to high doses of radiation. Although numerous classification systems have been described in the literature to describe the radiological extent of avascular necrosis of the femoral head, Ficat & Arlet and Steinberg University of Pennsylvania classification are the two most commonly used classification systems worldwide (Table  16.3). These grading systems help the surgeon in not only stratifying the disease but also in choosing the appropriate treatment for the patient. Although the grading systems differ, they have some common features like: Stage 1 Normal findings on plain radiograph. AVN is usually identified on MRI. Stage 2 Presence of a “Crescent sign” indicative of collapse of femoral head. Stage 3 Flattening of femoral head. Stage 4 Arthritic changes are visible on the acetabular side too. Joint preserving procedures like core decompression are usually advised for early stages of disease. Patients with collapse of femoral head (less than 2 mm) are candidates for bone grafting and rotational osteotomies of proximal femur. Total hip arthroplasty is usually reserved for advanced cases in which either the femoral head collapse is more than 2 mm or there is evidence of arthritic involvement of the acetabulum. In multiple studies, four radiological findings have been shown to have a prognostic value. The necrotic lesion should be classified with respect to collapse of the lesion. Thus, lesions can be classified as pre-collapse or post-collapse lesion. The next important radiological feature is the size of the lesion as larger or severe lesions are associated with higher chances of failure of joint salvage methods. Patients with less than 15% of head involvement are classified as having mild lesion. Moderate or medium lesions occupy between 15% and 30% of femoral head, whereas severe lesions occupy more than

S. Kacker and S. K. S. Marya

222 Table 16.3  Classification of AVN

Commonly used classification systems for AVN Ficat and Arlet University of Pennsylvania Stage Findings Stage Findings I Normal X-Ray 0 Normal radiograph and MRI II Diffuse cystic/sclerotic changes I MRI findings only A  Mild (less than 15% B  Moderate (15–30%) C  Severe (more than 30%) IIB Subchondral collapse (crescent II Diffuse cystic/sclerotic changes sign) A Mild B Moderate C Severe III Irregular femoral contour III Subchondral step off (crescent sign) A  Mild (less than 15% articular surface involvement) B  Moderate (15–30% articular surface involvement C  Severe (more than 30% articular surface involvement) IV Collapse of femoral head, IV Flattening of femoral head acetabular involvement, arthritic A  Mild (15% and less than 2 mm depression) changes B  Moderate (15–30% and 2–4 mm depression) C  Severe (more than 30% and more than 4 mm depression) V Joint space narrowing/acetabular changes A Mild B Moderate C Severe VI Advanced degenerative changes

30% of femoral head. Ito et al. has described presence of marrow edema around the lesion as an independent prognostic factor for disease progression [1]. They have reported that at 5-year follow-up, they found that all the lesions that had marrow edema failed within 3  years whereas lesions that had no marrow edema all around showed an excellent survivorship of 76% at 5-year follow-up. The next radiological feature to be ascertained is the change in the contour of the femoral head. Depression of the head (less than 2  mm) is usually associated with good outcomes where joint preservation procedures can be attempted. Collapse of femoral head of more than 2  mm is usually associated with poor outcomes. Berend et al. [2] reported outcomes at 5-year follow-up of free vascularized fibular grafting in 224 hips. He reported 69.9% survivorship in patients who had a collapse of femoral head of less than 1  mm, 66% survivorship in those who had a collapse between 2  mm and 3  mm, and 56.6% survivorship in patients having lesions more than 3 mm at the

time of vascularized fibular grafting. The last radiological factor to be considered is the presence of arthritic changes on the acetabular side. Presence of arthritic changes on the acetabular side virtually restricts our treatment options to total hip arthroplasty.

16.5 Treatment As with all forms of degenerative joint disorders, the main aim of treatment is early diagnosis and preservation of the native joint. This is particularly important with respect to AVN as a lot of patients diagnosed with AVN are comparatively younger as compared to patients suffering from other hip disorders.

16.5.1 Nonoperative Management The natural history of patients diagnosed with AVN who are asymptomatic is not clearly understood. Some surgeons have reported poor out-

16  Total Hip Arthroplasty in Avascular Necrosis of Hip

comes from non-operative management of asymptomatic patients [3, 4].However, Cheng et al. reported spontaneous resolution of osteonecrosis in 3 of 13 hips. They further suggested that spontaneous resolution of the lesion can occur in early small asymptomatic patients, especially those who have no evidence of avascular changes in the other hip [5]. In a review of more than 20 studies, protected weight bearing was found to be successful in only 22% of patients (182 of 819) hips [6]. The choice of different pharmacological medications is based on the presence of risk factors associated with the development of AVN in a particular patient. For example, a patient with hypercholesterolemia or hyperlipidemia can be treated by lipid-lowering medication like statins. Patients with coagulation disorders can be treated by anticoagulant treatment like heparin or warfarin. Bisphosphonates that act on osteoclasts have shown some promising results in earlier studies [7–10]. However a recent 2-year multicenter, prospective, randomized double-blind placebo-­ controlled trial did not show any significant differences in clinical outcomes between patients who used alendronate compared to patients who were given placebo [7]. It should be clearly understood that any pharmacological agent would be useful only till pre-­ collapse stage of the disease. It is doubtful that once there is a biomechanical failure (collapse), there is any role of any pharmacological agent for management of AVN.

16.5.2 Surgical Management Surgical management of AVN can be broadly divided into two groups. 1. Femoral head sparing procedures (FHSPs) 2. Femoral head replacing procedures (FHRPs) For treatment of early stages of AVN in which either there is no collapse of femoral head or the collapse is less than 2 mm joint preservation surgeries like core decompression, bone grafting, and rotational osteotomies are advocated.

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16.5.3 Femoral Head Sparing Procedures (FHSPs) 16.5.3.1 Core Decompression Core decompression is the most common procedure performed for the management of early AVN. It is believed that with an 8–10 mm reamer, a cylindrical channel is created up to the femoral head resulting in decompression of the raised intraosseous pressure and thereby reversing the pathology responsible for causing the osteonecrosis. The overall success of core decompression has been reported to be between 40% and 80% in various studies. However, the success and failure of core decompression also depend on the location, size and whether the avascular lesion is pre-­ collapse or post-collapse lesion. Lieberman et al. published their results of core decompression of 439 hips and reported failure rate of 14–25% for small lesions and 42–84% for large lesions [11]. 16.5.3.2 Multiple Drilling Multiple percutaneous drill holes in the femoral head is a safer and technically simpler alternative to core decompression [12, 13]. Multiple drill holes were made from lateral cortex of femur to the necrotic portion in femoral head with a 3.2 mm drill bit/Steinmann pin. Kang et al. conducted a prospective randomized study to compare the outcomes of multiple drilling plus alendronate with multiple drilling alone. They found that at 4-year follow-up, alendronate plus multiple drilling group showed 91% of patients with stage 2 disease and 62% of patients with stage 3 disease did not require conversion to THA. However in comparision, in the group in which only multiple drill holes were made (without alendronate), 79% of patients with stage 2 disease and 46% of patients with stage 3 disease did not require conversion to THA. Thus, they advocated that alendronate should be used in conjunction with multiple drilling for better clinical outcomes [14]. 16.5.3.3 Bone Grafting Procedures The use of nonvascularized bone graft (both autogenic and allogenic grafts, bone graft substitutes, non-vascularized fibula) to fill up defects created

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of porous tantalum rod for structural support. They reported an overall survival rate of 91.8% at 2  years, and 68.1% at 4  years follow-up. Although these results appear encouraging, concerns about generation of metal debris and a more complex surgical procedure are there if a need for THA arises. Further studies with longer follow-ups are required to assess clinical outcomes and survivorship of this technique. Fig. 16.2  Bilateral fibular grafting for AVN

by core decompression has been advocated by various authors. They believe that after the release of intraosseous pressure, the osteoconductive and osteoinductive environment provided by the bone graft helps in healing of the necrotic region. Various techniques of bone grafting like the Phemister grafting, light bulb procedure (making a window through femoral neck and filling in the graft), and trapdoor technique (making a window through the articular cartilage) have been described in the literature. Vascularized fibular or iliac crest grafting has been recommended by some surgeons as they believe the vascularized graft provides viable structural support and thus the osteoinductive potential with improved blood supply assists in better healing of the necrotic segment as compared to non-vascularized bone grafts (Fig. 16.2). The peroneal artery and vein harvested along with the fibular graft is anastomosed with the ascending branch of lateral circumflex femoral artery and vein. Urbaniak et  al. have published their results of vascularized bone grafting in 103 hips. At 5-year follow-up, they reported excellent 91% survivorship in stage II lesions and 77% survivorship in stage III lesions [15].

16.5.3.4 Tantalum Implants Core decompression followed by the usage of porous tantalum implants offers the advantage of providing structural support without the risks associated with bone grafting like infection and graft site morbidity [16–18]. Veillete et al. [18] evaluated 54 patients who underwent core decompression followed by the insertion

16.5.3.5 Biologics It is widely believed that even after core decompression and bone grafting, there is still a lack of progenitor cells that are required for new bone formation and healing of the necrotic segment. Hence, there has been great enthusiasm in instillation of osteogenic (mesenchymal stem cells) and osteoinductive bone morphogenic protein (BMP) around the necrotic bone to produce better bone healing. Gangji et al. [19] conducted a controlled, double-blind study and compared results of core decompression with infiltration of bone marrow aspirate with core decompression done alone. At 2-year follow-up, they reported a significant difference in time to collapse between the two groups. They also reported a 35% reduction in the size of necrotic fragments in the bone marrow graft group. Various methods of instillation of stem cells into the necrotic region of the femoral head have been described. The most commonly performed procedure is the direct instillation of the core tract. Other procedures like selective femoral arterial perfusion or catheterization of the medial, lateral, or obturator artery are technically more demanding. Proponents of stem cell therapy believe that regeneration of the osteonecrotic fragment is dependent on the concentration of the stem cells with larger lesions, requiring more volume of instillation [20]. However, inspite of all the enthusiasm surrounding this procedure, the available data at this point of time is preliminary and multicenter long-term studies are required to establish its efficacy. 16.5.3.6 Osteotomy The aim of osteotomies around proximal femur is to rotate the affected avascular fragment away

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from weight-bearing portion of the femoral head and bring a healthy viable portion of femoral head in the weight-bearing region. Both varus and valgus angular intertrochanteric osteotomies and rotational transtrochanteric osteotomies have been described in literature for the treatment of AVN with varying success rates [21–25]. Sugioka reported a 78% success rate in his series of patients at 3–16  years follow-up. However, the promising success rates reported by Sugioka have not been reproduced by other authors in the literature. These osteotomies can provide a painless, mobile, and stable hip after rotation of the involved necrotic area only if the depth of necrosis is not larger than one-third of the diameter of the femoral head. Hisatome et al. [25] reviewed 25 hips who had undergone Sugioka’s anterior rotational osteotomy for AVN. At 6-year followup, they found that there was no collapse of the new weight-bearing region of the femoral head. However, they reported progressive collapse in the anteriorly rotated necrotic fragment inducing joint instability and arthritic changes. Despite offering advantages of joint preservation, especially in younger individuals, the proximal femoral osteotomies do provide a challenge when the need arises to convert them to total hip arthroplasty. Changes in femoral version, prominence of greater trochanter making entry into the femoral canal for stem insertion difficult, presence of metallic hardware, and incision marks all have been reported to adversely affect the clinical outcomes of total hip arthroplasty in this subgroup of patients.

future revision surgeries. However, concerns regarding acetabular erosion, implant migration, and groin pain reported after bipolar hemiarthroplasty have led to questions being raised on the option of using bipolar hemiarthroplasty as a treatment for AVN. Arthroplasty is usually offered as a treatment for end-stage osteonecrosis and it has been widely reported in the literature that the incidence of acetabular erosion and implant migration is higher in patients suffering from grade IV osteonecrosis as compared to patients having stage II or III disease. Tsumara et al. [26] studied 30 patients with AVN ranging from stage II to stage IV disease and at a mean follow-up of 7.7 years reported a significantly higher incidence of medial (0.1  mm vs. 3.5  mm) and superior migration (0.5  mm vs. 3  mm) of implant in patients suffering from stage IV disease as compared to patients with stage II disease.

16.5.4 Femoral Head Replacement Procedures • Bipolar hemiarthroplasty. • Resurfacing arthroplasty. • Total hip arthroplasty.

16.5.4.1 Bipolar Hemiarthroplasty Bipolar hemiarthroplasty as a treatment for AVN was advocated on the belief that it is technically less demanding, is less invasive for the patient, has lesser complications compared to THA, and it helps in preserving acetabular bone stock for

16.5.4.2 Resurfacing Arthroplasty A large number of patients suffering from AVN are young and are generally expected to outlive the primary arthroplasty surgery. Conservation of proximal femoral bone stock is desirable in these younger individuals keeping in mind that a future revision surgery might be required. Advocates of resurfacing arthroplasty feel that resurfacing especially in younger and active individuals provides similar pain relief and equal improvement in activity and quality of life as compared to total hip arthroplasty [27–31]. They further believe that there are certain advantages of resurfacing as compared to THA like preservation of proximal femoral bone stock, more physiological loading of femur, more normal gait, lesser chances of dislocation, and a technically less challenging revision surgery if the need arises in future [27, 29, 32]. However, resurfacing arthroplasty is technically demanding surgery with strict inclusion and exclusion criteria. In literature, various studies have reported excellent short- to mid-term results of resurfacing arthroplasty as a treatment for end-stage AVN. Revel et al. [33] reported implant survivorship of 93.2% in their study of 73 osteonecrotic hips at a mean follow-up of 6.1 years. Similarly, Mont et  al. reported implant survivorship of 100% at a mean follow-up of 7.5  years in their

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study of 20 osteonecrotic hips all under the age of 25 years [34]. Mont et al. [27] also did a comparative analysis of the results of resurfacing arthroplasty in AVN and OA. At final follow-up of 3.4 years, both the groups reported a similar Harris hip score of 91. The implant survivorship in AVN group was 94.5% as compared to 95.2% in OA group. Patient-specific factors like younger age (less than 55 years) male gender and larger head sizes (more than 50  mm) have been found to be associated with more favorable outcomes [35–37]. However inspite of the advantages, some concerns have been raised against resurfacing ­arthroplasty. Detractors of resurfacing argue that there is progression of osteonecrosis under the implant surface, which leads to early loosening of femoral component and neck fractures. They also advocate that the use of metal-on-metal articulation in resurfacing may lead to elevated metal ion levels, metal hypersensitivity, and adverse local tissue reactions. In recent years due to these concerns, the popularity of resurfacing arthroplasty has waned. However, some recent studies have shown improved mid-term–long term outcomes for uncemented metal-on-metal hip resurfacing compared with cemented hip resurfacing arthroplasty [38].

Fig. 16.3  Right THA for AVN

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16.5.4.3 Total Hip Arthroplasty THA is considered as treatment of choice for patients suffering from end-stage osteonecrosis as it provides long-term pain relief and restoration of functional activity and quality of life (Fig.  16.3). The results of THA for AVN has vastly improved over the decades but still patients undergoing THA for AVN tend to have less optimal outcomes as compared to patients undergoing THA for osteoarthritis [39, 40]. Moreover, not only sub-optimal outcomes but higher rates of complications after THA in AVN have also been reported [41]. This can be attributed to various factors common in patients suffering from AVN like: (a) younger age group of patients at the time of presentation as compared to patients with osteoarthritis, (b) presence of systemic disorder associated with AVN, (c) abnormal bone quality of femur and acetabulum, (d) previous surgical procedures involving the hip. In general, patients with AVN are younger as compared to patients suffering from osteoarthritis. If we review the literature, we find that

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younger age group in itself is associated with poorer outcomes after THA as compared to older group irrespective of the etiology for which THA was performed. This younger age group is more active and has more functional demands as compared to the older age group, which may account for some of the differences in results. There are several conditions associated with AVN that contributes to less optimal outcomes in these patients. Long-term steroid use, ­alcoholism, sickle cell disease, autoimmune disease, renal failure, and trauma all increase the likelihood of developing AVN and in turn are also associated with poor early and long-term results of THA. The quality of bone in proximal femur and acetabulum in patients of AVN is also different from patients with any other pathology. Arlot et  al. [42] evaluated histomorphometry of 77 patients suffering from AVN.  Bone biopsy was done from iliac crest and the harvested bone was subjected to histomorphometric analysis. They evaluated trabecular bone volume, trabecular osteoid volume, trabecular osteoid surface, calcification rates, and bone formation rates at multicellular unit level and tissue level. They reported that there was a marked decrease in osteoblastic appositional rate as well as bone formation rate both at the cellular level and at the tissue level. Tingart et  al. [43] compared the histologic characteristics of cancellous bone of AVN patients with patients suffering from osteoarthritis. They took cancellous bone from the greater and lesser trochanters and from metaphyseal area 4  cm distal to lesser trochanter. They found a greater number of osteoblasts and osteocytes in greater trochanter area of patients with AVN as compared to patients with OA. They also found altered microstructure of trabeculae in metaphyseal area below LT in patients with AVN as compared to OA.  With these findings, they hypothesized that in patients with AVN, abnormal bone turnover and architecture are not only restricted to femoral head but also extend down to metaphyseal area. The presence of dense sclerotic bone especially seen in patients with sickle cell disease impedes both osseointegration as well as cement interdigitation, leading to poorer results in these patients. The presence of this altered bony architecture might explain the cause

of early aseptic loosening of the femoral component in patients with AVN as reported in some studies [44–46]. In some patients with AVN, THA is not the primary surgery and usually, some surgical procedure has been done in the past in an attempt to prevent the collapse of the femoral head. These prior surgical interventions alter the surgical anatomy, posing substantial challenges while performing the THA and can be a cause for poorer results of THA in these subgroups of patients (Fig. 16.4). Preoperative Planning While planning for THA, it is imperative to first optimize the underlying medical condition causing AVN.  Whenever dealing with sickle cell patients, a hematologist should be part of the multidisciplinary team. Factors precipitating sickling like hypovolemia, hypothermia, acidosis, and pain should be adequately managed in preop, periop, and postoperative period. Preoperative templating might help the surgeon in identifying the altered anatomy (if any) or presence of implant and preparing how to deal with it intraoperatively. As a large majority of patients undergoing THA for AVN are relatively younger, preop templating also helps in improving the surgeons ability to restore offset, stability, and limb length that is very important for not only improving patient satisfaction but also long-­ term survival of THA. Intraoperatively, it must be kept in mind that the quality of bone in AVN patients is less robust as compared to patients with osteoarthritis. One has to be extra careful while reaming and broaching the femoral canal. It is advisable to prophylactically wire the femur to prevent iatrogenic fractures before preparing the femoral canal. Similarly, one has to be careful while reaming the acetabulum as aggressive reaming may result in too much bone loss resulting in proximal and medial seating of acetabular component. On the other hand, in patients with sickle cell anemia, the bone is sclerotic and very hard due to bony infarcts caused by repeated episodes of sickling. Use of high-speed burr and reaming tools under radiographic guidance is highly recommended in these patients to avoid iatrogenic fractures and component malpositioning.

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Fig. 16.4  Total hip arthroplasty post fibular grafting for AVN

Similarly, sometimes patients with AVN present with a failed core decompression with fibular graft or tantalum implant in situ. Meticulous planning is required in these patients as the fibular graft or tantalum implant needs to be adequately removed for proper placement of the femoral component. Davis et  al. [47] have reported worse outcomes after THA in patients who underwent fibular grafting before THA as compared to patients without fibular grafting. They used three different types of stem in patients with fibular graft in situ—a straight stem, a tapered stem fixed after using a high speed burr to remove more of fibular graft, and a tapered stem without the use of high-speed burr. Worst alignment (mean 6.7degrees Varus) was reported in tapered stem group where the high-speed burr was not used. The best alignment (mean 0.4 degrees Valgus) was reported in the group where tapered stem was used after removal of fibular graft with high-speed burr. The results with usage of straight stem were intermediate (mean 3.5 degrees Varus). They recommended the use of high-speed burr for the removal of fibular graft for improving alignment of femoral component.

Tanzer et al. [48] studied the results of THA in 17 patients after failed core decompression with tantalum metal graft in situ. They reported a large quantity of metallic debris after the implant and femoral neck had been transected. Although long-term effect of tantalum particles is not known, it is believed that the metallic debris can lead to accelerated wear of bearing surfaces. They further recommended that the use of an osteotome as compared to a high-speed oscillating saw leads to the generation of a lesser amount of metallic debris. Similarly, THA after a previous intertrochanteric or transtrochanteric osteotomy is a technically demanding surgery due to altered proximal femoral anatomy. Changes in femoral version, prominence of greater trochanter making entry into the femoral canal for stem insertion difficult, presence of metallic hardware, and incision marks all have been reported to adversely affect the clinical outcomes of total hip arthroplasty in this subgroup of patients. Osawa et al. [49] compared the results of THA after transtrochanteric rotational osteotomy(34 hips) with patients who underwent THA as primary surgery for AVN (68

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hips). They reported poorer Harris hip scores as well as poorer ROM in post osteotomy group as compared to the other group. At 10-year ­follow-­up, implant survivorship was reported as 81% in the post osteotomy group as compared to 91% in the primary THA group. Implant Options With the development of present-generation uncemented implants, improvement in cementing techniques, development of newer highly porous stem designs, and newer generation bearing surfaces more encouraging results of better survivorship have been reported in patients undergoing THA for AVN.  Kim et  al. reported outcomes of hybrid and uncemented fixation in 98 patients with AVN [50]. They reported survivorship of 98% for both cemented as well as uncemented stems at a mean follow-up of 17.3 years. They further reported 85% survivorship of uncemented cups as compared to 83% of hybrid cups at the time of final follow-up. The main cause of failure was acetabular wear and peri articular loosening. Bedard et al. reported functional and clinical outcomes in 80 patients who underwent THA for AVN. At 10-year follow-up, they reported 100% survivorship of both the stem as well as the cup [51]. However, at final follow-up, they reported a 7.5% incidence of periacetabular osteolysis and 21% incidence of proximal femoral osteolysis. They hypothesized that polyethylene wear was the main concern with patients having conventional polyethylene liners showing higher linear and volumetric wear as compared to patients who had highly cross-linked polyethylene. Recent advances in tribology have led to the development of newer generation of ceramics and highly cross-linked polyethylene. The third generation of ceramics with potential benefits of improved wettability, scratch resistance, and lesser wear have proven to be advantageous when used as bearing surfaces in patients of AVN.  Similarly, development of highly cross-­ linked polyethylene has resulted in reduction of both adhesive as well as abrasive wear associated with ultra-high molecular weight polyethylene. The improved results of THA in patients of AVN can be attributed to the production of less wear particles associated with the use of third-­

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generation ceramics along with highly cross-­ linked polyethylene. In 162 patients with AVN having highly cross-­ linked polyethylene as bearing surface, Min et al. reported 100% survivorship at 10-year follow-up [52]. Similarly, Byun et  al. reported 100% implant survivorship at a mean follow-up of 7.7  years when using third-generation ceramic-­ on-­ceramic articulation [53]. Ancelin et al. [54] did a case–control prospective study in 282 patients less than 65  years of age. The cases group comprised 149 patients who underwent THA for AVN, whereas the control group consisted of 133 patients who underwent THA for primary osteoarthritis. They studied implant survival, complication rates, functional, and radiological outcomes in the two groups and tried to determine whether specific risk factors for failure of THA existed in patients of AVN. In both groups, an uncemented implant with 28 mm metal-on-metal articulation was used. The 10-year survival rates were similar in the two groups. For major revisions, the AVN group had a survivorship of 92.5% as compared to 95.3% in the OA group. For aseptic loosening, AVN group had survivorship of 98.6% and OA group had a survivorship of 99.2%. However, The AVN group had higher numbers of revision for any reason 19 vs. 6 in OA group and for dislocation 8 in AVN group vs. 1  in OA group (8 vs. 1, P  =  0.031). Thus, the authors concluded that survival in this study was good and consistent with recent data on AVN, with no statistically significant difference between AVN and OA. Similarly, functional and radiological outcomes were similar in the both the AVN and OA groups. However, revisions for any cause or for dislocation were more common after THA for AVN. THA in High-Risk Patients In literature, earlier studies have reported poor outcomes with high rates of revision in patients of AVN with sickle cell disease, Gaucher’s disease, and post-renal transplant patients. These poorer outcomes are related to higher rates of infection and higher rates of medical and surgical complications in these patients. In addition to this sickle cell anemia presents unique perioperative challenges like hypovolemia, hypothermia, and acidosis, which precipitates

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sickling and in turn leads to higher rates of perioperative morbidity and mortality. However, recent studies have reported better clinical outcomes after THA even in these high-risk patients. Issa et  al. [55] compared clinical and functional results of THA in 42 patients with sickle cell disease and 102 patients with nonsickle AVN.  At a mean follow-up of 7  years, they reported comparable implant survivorship and Harris hip scores in both the groups. Chang et al. [56] in a retrospective study analyzed the results of THA in 74 post-renal transplant patients. At a follow-up of 10.2  years, they reported 96.6% implant survivorship with a mean Harris hip score of 89 points. Short Femoral Stem Short-stem arthroplasty was introduced with the aim to: (a) Preserve proximal femoral bone stock. In younger individuals, it not only preserves the proximal bone stock by more physiological loading of the joint but the usage of a short stem instead of conventional stem at the time of primary THA also conserves the bone for

Fig. 16.5  Use of short femoral stem (proxima) and tri-lock

S. Kacker and S. K. S. Marya

future in case a revision surgery is required at a later date. (b) Reduce incidence of thigh pain seen with use of conventional stems. (c) Allow stem insertion through minimally invasive techniques. Some studies at short-term follow-up reported excellent survivorship between 96% and 100% [57–60]. However, usage of short stem did not gain huge popularity among surgeons primarily as the procedure was technically demanding and had a steep learning curve. The authors have had excellent functional and clinical results with the usage of short stems, especially in younger patients (Fig. 16.5). However, one should always keep a conventional stem in his armamentarium as a backup. As compared to earlier studies, recent studies have shown excellent short- to mid-term survivorship of THA in patients of AVN.  However, more clinical trials with longer follow-ups are required before it can be conclusively said that clinical outcomes of THA in patients with AVN are comparable with outcomes of THA done for any other etiology.

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16.6 Summary Clinical suspicion of AVN needs to be corroborated with X-ray and MRI findings. The natural course and progression of AVN are still not completely understood and hence it is difficult to evaluate whether any specific treatment modality alters the natural course of disease or not. Medical and surgical management have been shown to provide pain relief and early intervention before collapse of osteonecrotic segment has been critical to successful outcomes of joint preserving procedures. However, it is still debatable whether joint preservation procedures can alter the natural course of disease and can heal the necrotic fragment or they just slow down the progression of the disease. Future research should be directed at identifying treatment strategies that cannot only stop the natural progression of disease but also initiate healing and revascularization of necrotic fragment, thereby preventing collapse and the need for THA.

References 1. Ito H, et al. Relationship between bone marrow edema and development of symptoms in patient with osteonecrosis of femoral head. AJR Am J Roentgenol. 2006;186:1761–70. 2. Berend KR, et al. Free vascularized fibular grafting for the treatment of postcollapse osteonecrosis of femoral head. J Bone Joint Surg Am. 2003;85-A:987–93. 3. Bradway JK, et  al. The natural history of silent hip in bilateral atraumatic osteonecrosis. J Arthroplast. 1993;8:383–7. 4. Stulberg BN, et  al. Osteonecrosis of femoral head. A prospective randomized treatment protocol. Clin Orthop Relat Res. 1991;268:140–51. 5. Cheng EY, et  al. Spontaneous resolution of osteonecrosis of femoral head. J Bone Joint Surg Am. 2004;86-A:2594–9. 6. Mont MA, et  al. Core decompression versus non operative management for osteonecrosis of the hip. Clin Orthop Relat Res. 1996;324:169–78. 7. Chen CH, et  al. Alendronate in the prevention of collapse of the femoral head in nontraumatic osteonecrosis: a two year multicenter prospective, randomized, double blind, placebo controlled study. Arthritis Rheum. 2012;64:1572–8.

231 8. Peled E, et  al. Prevention of distortion of vascular deprivation –induced osteonecrosis of the rat femoral head by treatment with alendronate. Arch Orthop Trauma Surg. 2009;129:275–9. 9. Agarwala S, et  al. The use of alendronate in the treatment of avscular necrosis of the femoral head. Follow-up to eight years. J Bone Joint Surg (Br). 2009;91:1013–8. 10. Agarwala S, et  al. Ten year follow-up of avascular necrosis of femoral head treated with alendronate for 3 years. J Arthroplast. 2011;26:1128–34. 11. Lieberman JR, et al. Which factors influence preservation of the osteonecrotic femoral head ? Clin Orthop Relat Res. 2012;470:525–34. 12. Song WS, et al. Results of multiple drilling compared with those of conventional methods of core decompression. Clin Orthop Relat Res. 2007;454:139–46. 13. Lee MS, et al. Elevated intraosseous pressure in the intertrochanteric region is associated with poorer results in osteonecrosis of the femoral head treated by multiple drilling. J Bone Joint Surg. 2008;90:852–7. 14. Kang P, et al. Are the results of multiple drilling and alendronate for osteonecrosis of femoral head better than those of multiple drilling. ?A pilot study. Joint Bone Spine. 2012;79:67–72. 15. Urbaniak JR, et  al. Treatment of osteonecrosis of femoral head with free vascularized fibular grafting. A long term follow-up study of one hundred and three hips. J Bone Joint Surg Am. 1995;77:681–94. 16. Shuler MS, et  al. Porous tantalum implant in early osteonecrosis of the hip: preliminary report on operative survival and outcomes results. J Arthroplast. 2007;22:26–31. 17. Tsao AK, et  al. Biomechnaical and clinical evaluations of a porous tantalum implant for treatment of early –stage osteonecrosis. J Bone Joint Surg Am. 2005;87(Suppl2):22–7. 18. Veillette CJ, et  al. Survivorship analysis and radiographic outcome following tantalum rod insertion for osteonecrosis of femoral head. J Bone Joint Surg Am. 2006;88(Suppl 3):48–55. 19. Gangji V, et al. Treatment of osteonecrosis of femoral head with implantation of autologous bone marrow cells. A pilot study. J Am Bone Joint Am. 2004;86(6):1153–60. 20. Hernigou P, et  al. The use of percutaneous autologous bone marrow transplantation in nonunion and avascular necrosis of bone. J Bone Joint Surg (Br). 2005;87:896–902. 21. Dean MT, et  al. Transtrochanteric anterior rotational osteotomy for avascular necrosis of the femoral head. Long-term results. J Bone Joint Surg (Br). 1993;75:597–601. 22. Langlais F, et  al. Rotation osteotomies for osteonecrosis of the femoral head. Clin Orthop Relat Res. 1997;343:110–23.

232 23. Tooke SM, et  al. Results of transtrochanteric rotational osteotomy for femoral head osteonecrosis. Clin Orthop Relat Res. 1987;224:150–7. 24. Sugioka Y. Transtrochanteric anterior rotational osteotomy of the femoral head in the treatment of osteonecrosis affecting the hip: a new osteotomy operation. Clin Orthop Relat Res. 1978;130:191–201. 25. Hisatome T, et al. Progressive collapse of transposed necrotic area after transtrochanteric rotational osteotomy for osteonecrosis of the femoral head induces osteoarthritic change. Mid-term results of transtrochanteric rotational osteotomy for osteonecrosis of the femoral head. Arch Orthop Trauma Surg. 2004;124:77–81. 26. Tsumara H, et al. Five to fifteen year clinical results and the radiographic evaluation of acetabular changes after bipolar hip arthroplasty for femoral head osteonecrosis. J Arthroplast. 2005;20:892–7. 27. Mont MA, et  al. Use of metal on metal Total hip resurfacing for the treatment of osteonecrosis of the femoral head. J Bone Joint Surg Am. 2006;88(suppl 3):90–7. 28. Schmalzried TP. Total resurfacing for osteonecrosis of the hip. Clin Orthop Relat Res. 2004;429:151–6. 29. McGrath MS, et  al. Surface replacement is comparable to primary total hip arthroplasty. Clin Orthop Relat Res. 2009;467:94–100. 30. Rahman WA, et  al. Patients report improvement in quality of life and satisfaction after hip resurfacing arthroplasty. Clin Orthop Relat Res. 2013;471:444–53. 31. Aulakh TS, et al. Hip resurfacing and osteonecrosis: results from an independent hip resurfacing register. Arch Orthop Trauma Surg. 2010;130:841–5. 32. Aqil A, et al. The gait of patients with one resurfacing and one replacement hip: a single blinded controlled study. Int Orthop. 2013;37(5):795–801. 33. Revell MP, et  al. Metal on metal hip resurfacing in osteonecrosis of femoral head. J Bone Joint Surg Am. 2006;88(suppl-3):98–103. 34. Mont MA, et  al. Does the extent of osteonecrosis affect the survival of hip resurfacing ? Clin Orthop Relat Res. 2013;471(6):1935–6. 35. Hart AJ, et al. Which factors determine the wear rate of large diameter metal on metal hip replacements?. Multivariate analysis of two hundred and seventy six components. J Bone Joint Surg Am. 2013;95: 678–85. 36. Schmalzried TP.  Why total hip resurfacing. J Arthroplast. 2007;22:57–60. 37. Liu F, et  al. A safe zone for acetabular component position in metal on metal hip resurfacing arthroplasty. J Arthroplast. 2013;28(7):1224–30. 38. O'Leary RJ, et al. Comparison of cemented and bone ingrowth fixation methods in hip resurfacing for osteonecrosis. J Arthroplast. 2017;32:437–46. 39. Issa K, et  al. Excellent results and minimal complications of total hip arthroplasty in sickle cell hemoglobinopathy at mid term follow -up using cementless prosthetic components. J Arthroplast. 2013;28(9):1693–8.

S. Kacker and S. K. S. Marya 40. Issa K, et al. Hip osteonecrosis: does prior hip surgery alter outcomes compared to an initial primary total hip arthroplasty? J Arthroplast. 2014;29(1):162–6. 41. Johannson HR, et  al. Osteonecrosis is not a predictor of poor outcomes in primary total hip arthroplasty. A systematic literature review. Int Orthop. 2011;35:465–73. 42. Arlot ME, et al. Bone histology in adults with aseptic necrosis: histomorphometric evaluation of iliac biopsies in seventy-seven patients. J Bone Joint Surg Am. 1983;65:1319–27. 43. Tingart M, et. al. Analysis of bone matrix composition and trabecular microarchitecture of the femoral metaphysis in patients with osteonecrosis of the femoral head. J Orthop Res. 2009;27:1175–81. 44. Wroblewski BM, et al. Charnley low-frictional torque arthroplasty for avascular necrosis of the femoral head. J Arthroplast. 2005;20:870–3. 45. Baek SH, et al. Cementless total hip arthroplasty with alumina bearings in patients younger than fifty with femoral head osteonecrosis. J Bone Joint Surg Am. 2008;90:1314–20. 46. Calder JD, et al. The extent of osteocyte death in the proximal femur of patients with osteonecrosis of the femoral head. J Bone Joint Surg (Br). 2001;83:419–22. 47. Davis ET, et al. Total hip arthroplasty following failure of free vascularized fibular graft. J Bone Joint Surg Am. 2006;88(suppl-3):110–5. 48. Tanzer M, et  al. Histopathologic retrieval analysis of clinically failed porous tantalum osteonecrosis implants. J Bone Joint Surg Am. 2008;90:1282–9. 49. Osawa Y, et  al. Total hip arthroplasty after transtrochanteric rotational osteotomy for osteonecrosis of the femoral head: a mean 10-year follow-up. J Arthroplast. 2017;32(10):3088–92. 50. Kim YH, et  al. Contemporary total hip arthroplasty with and without cement in patients with osteonecrosis of the femoral head: a concise follow-up, at an average of seventeen years, of a previous report. J Bone Joint Surg Am. 2011;93:1806–10. 51. Bedard NA, et  al. Cementless THA for the treatment of osteonecrosis at 10 year follow-up: have we improved compared to cemented THA? J Arthroplast. 2013;28(7):1192–9. 52. Min BW, et  al. Highly crosslinked polyethylene in total hip arthroplasty for osteonecrosis of the femoral head: a minimum 5 year follow-upstudy. J Arthroplast. 2013;28:526–30. 53. Byun JW, et al. Third generation ceramic on ceramic total hip arthroplasty in patients younger than 30 years with osteonecrosis of femoral head. J Arthroplast. 2012;27:1337–43. 54. Ancelin D, et  al. Total hip arthroplasty survival in femoral head avscular necrosis versus primary hip osteoarthritis: case control study with a mean 10 year follow –up after anatomical cementless metal on metal 28 mm replacement. Orthop Traumatol Surg Res. 2016;102(8):1029–34. 55. Issa K, et  al. Excellent resukts and minimal complications of total hip arthroplasty in sickle cell

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hemoglobinopathy at mid term follow-up using cementless prosthetic components. J Arthroplast. 2013;28(9):1693–8. 56. Chang JS, et al. Cementless total hip arthroplasty in patients with osteonecrosis after kidney transplantation. J Arthroplast. 2013;28:824–7. 57. Floerkemeier T, et  al. Cementless short stem hip arthroplasty METHA(R) as an encouraging option in adults with osteonecrosisof the femoral head. Arch Orthop Trauma Surg. 2012;132:1125–31.

58. Wang YS, et al. Application of CFP short stem prosthesis in treatment of osteonecrosis of the femoral head. Zhonghua Yi Xue Za Zhi. 2011;91:3320–3. 59. Kim YH, et  al. A prospective short term outcome study of a short metaphyseal fitting total hip arthroplasty. J Arthroplast. 2012;27:88–94. 60. Zeh A, et al. Medium term results of Mayo short stem hip prosthesis after avascular necrosis of femoral head. Z Orthop Unfall. 2011;149:200–5.

Total Hip Arthroplasty in Dysplastic Hips

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Vijay C. Bose, Kalaivanan Kanniyan, and Alex Muttathupadam

17.1 Introduction Dysplasia of the acetabulum, or insufficient coverage of the femoral head, is seen in a large number of individuals. It may be a sequel of a childhood developmental dysplasia of the hip. Infections in the growing age, involving either the longitudinal growth plate of the femur or the triradiate cartilage may lead to alterations in the morphology of both femoral head and acetabulum in adulthood. A traumatic injury involving the above-mentioned cartilages also can result in similar morphology. Conditions causing hyperemia to the femoral head, such as inflammatory pathologies, cause coxa magna and subluxation because the head enlarges faster than the acetabulum, leading to a dysplastic morphology [1]. A good number of such patients are pain-free for a variable period of their life. However, the reduced area of the acetabular cartilage surface, hypertrophy of the labrum, and elongation of the ligamentum teres accompanying lateral subluxation of the femoral head can lead to tears of the labrum and ligamentum teres and articular cartilage injury. These conditions eventually contribute to the degeneration of the hip in the setting of dysplasia [2]. About 20–40% of osteoarthritis of the hip is related to DDH [3]. Wiberg, in his study about congenital subluxation of the hip, noted

V. C. Bose (*) · K. Kanniyan · A. Muttathupadam Asian Orthopaedic Institute, Chennai, India

that all of his patients with definite subluxation showed evidence of osteoarthritis by the age of 50–60 years. A dysplastic hip with degenerative arthritis is a complex problem to deal with. Out of the various treatment modalities described varying from arthroscopic procedures to peri acetabular osteotomies, total hip arthroplasty(THA) is the mainstay providing a painless, mobile, and stable hip joint to the patient. The altered anatomy and resultant change in biomechanics make accurate positioning of both femoral and acetabular components difficult.

17.2 Patho-Anatomy and Classification The anatomical abnormality of a dysplastic acetabulum is not restricted to a single plane or dimension. It is globally deficient both in shape and orientation. The width of the socket remains more or less comparable to a nondysplastic socket, but the length is increased and the depth is decreased. The acetabulum appears oblong and shallow. This shape is represented by a decreased lateral center edge angle (LCEA). LCEA, which is an indication of the extent of lateral acetabular bony coverage, was originally defined by Wiberg [4] as the angle between a line from the center of the femoral head and parallel to the longitudinal body axis and a line from the center of the femoral head to the most lateral point of the acetabular roof.

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Shah et al. [5] used LCEA to classify hip dysplasia into borderline, mild, moderate, and severe (Table 17.1). The deviation from normal anatomy can range from a very minimal alteration in the center-edge angle to a complete high dislocation. Even in patients with hip dysplasia, the poor coverage of the femoral head, the relative lateralization of the hip center of rotation, and the smaller contact area between the femoral head and the dysplastic acetabulum can produce an asymmetric concentration of force across the hip joint, leading to secondary articular cartilage and labral damage. This explains the eventual development of arthritis in almost all dysplastic hips. The acetabular anteversion of dysplastic hips is much larger than that of normal hips. However, Mast, Li and Ganz et al. [6] noted retroversion of the socket in one in three hips. One of the most widely used classification was put forward by Crowe et  al. in 1979 (Fig. 17.1) [7]. It is based on three easily identifiable anatomic landmarks: (1) the height of the pelvis; (2) the medial head–neck junction in the affected hip; and (3) the inferior margin of the acetabulum (the teardrop). The reference line is Table 17.1  The severity of dysplasia according to the LCEA Dysplasia Borderline Mild Moderate Severe

LCEA 20–24 15–19 10–14 3–4 cm lengthening. Subtrochanteric osteotomy is indicated in this situation to decompress the soft tissue [15]. We use a posterior approach for Crowe 4 indications. The capsule that is tubular is opened and followed inferiorly till the true socket is reached. The socket is usually triangular with narrow columnar bone converging over the top of the socket. The native socket is very small and will not accommodate even the smallest size of uncemented socket. Hence columnar bone has to be borrowed. The trial socket of small dimension is placed open side down on bone to gauge as to where bone is available for reaming. This is marked and reaming is done carefully so as to preserve columnar continuity. Usually, the socket size would be 40 mm or less. Screws are used to augment stability. After

socket preparation, the femur is prepared with an S-ROM system. Invariably reduction is not possible and STSO is performed about 1.5 to 2  cm below the metaphyseal sleeve. Osteotomy too close to the sleeve will compromise sleeve stability and if done too distally will interfere with achieving distal scratch fit of the stem. After a transverse osteotomy at this level, the femoral trial is placed into the proximal fragment, the head reduced into the acetabulum, and traction applied to the distal femur. The bony overlap at the osteotomy level shows the amount of bone to be removed from the distal segment. The femoral trial is then reinserted transfixing the osteotomy. Hip is then reduced, and soft tissue and sciatic nerve tension are assessed. The resection has to be conservative to avoid over resection as over resection causes potential instability. Additional bone can be resected sequentially if necessary. After appropriate soft tissue tension and stability are achieved, the final proximal sleeve and stem components are inserted with the femur and prosthetic femoral neck oriented in relation to the long axis of the tibia (Fig.  17.11). Stability at the site of osteotomy must be rigid. If not, a 3.5 mm locking plate is added to give rotational stability (Fig. 17.12).

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Fig. 17.12  Showing pre-op and post-op pics of Crowe 4 dysplasia managed with a small uncemented socket and STSO on the femoral side

Fig. 17.13  Pics of case 1 showing the pre-op X-rays of different types of dysplasia on either side and post-op X-rays showing the limb lengths being equal

17.5 Case Discussions Case 1 (Fig.  17.13)  Thirty four-year-old female patient with severe hip pain for the last 4  years. Significant limp was present . X-rays

showed severe dysplasia on both sides with a very shallow medial wall. Interesting factors in the case was that the dysplasia was very asymmetrical with a significant limb length discrepancy. The challenge was to equalize the limb

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Fig. 17.14  Pics of case 2 showing the pre-op X-rays showing X-ray evidence of a triple innominate osteotomy on the right side. Post-op X-ray showing good coverage of socket

length of the two sides showing different patterns of dysplasia. Staged reconstruction of both hips was done with the left side first. The right side was done after 2  weeks so the right side can be done in such a way that the limb length will be equal. Case 2 (Fig. 17.14)  Thirty eight-year-old female patient who had a triple innominate osteotomy performed 12  years ago presented to us with advanced symptoms of Osteoarthritis in the right hip. She had a antalgic gait and restriction of ROM. She gave an history of having very minimal symptoms with only pain on high flexion activities for 12 years ago when the triple innominate osteotomy was performed. This case illustrates the fact that the natural history of secondary OA may not change even after a well-done osteotomy if it is later in life. Technically there are challenges in placement of the socket after a triple innominate osteotomy. The cover of the socket is improved after triple osteotomy but this is not required with modern highly porous implants, which show good survival rates even with less host bone contact.

17.6 Discussion Encountering some form of dysplasia is not uncommon while performing total hip arthroplasties. Harris speculated that dysplasia is seen in 80% of routine total hip replacements (THRs) performed in women, and 15% in men. Most of the cases are sequelae of developmental dysplasia of hip. Even though severe arthritic joints as a result of development DDH seem to be decreasing, we still encounter a good number of dysplastic hips requiring THA. The presence of different anatomical abnormalities, including those of the soft tissues, the acetabulum and proximal femur, making a successful THA technically demanding. Recently, patients are increasingly expecting better restoration of function. Younger patients with a higher activity demand necessitate the surgeon to provide the patient the best result possible. A good understanding of the anatomical variations and associated conditions is vital in pre-­ operative planning. One of the main reasons for patient dissatisfaction after THA is perceived leg length discrepancy [16]. Postoperative LLD can be a consequence of several factors, such as cup position,

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inequalities in bony structure and pelvic tilt. According to Li et al. [16], there are three types of LLD in patients with DDH: bony, anatomical, or functional. Whether unilateral or bilateral, if no fixed pelvic tilt is shown, then anatomical LLD should be applied during THA.  Otherwise, functional LLD should be the first choice to balance leg length. The traditional teaching of restoring the anatomical center in all types of dysplasia is changing. Pagnano et al. reported high failure rates with cemented acetabular components placed at high hip center [17]. However, Harris et al. published good results with high hip center using uncemented acetabular components. Ranawat et  al. showed excellent outcomes and high survivorship at 10 years with uncemented acetabular fixation at high center. In the present day, there is enough evidence to conclude that a well-­medialized uncemented cup at a moderate high center provides excellent long-term results. We recommend cup placement on the best available bone. 3D CT study by van Bosse et al. describes the shape of the dysplastic segment and its bony architecture. In types II and III, the best available bone is in the pseudo acetabulum, whereas in type IV, the native acetabulum has the best bone quality.

17.7 Summary • Cup placement should be at the best bone available. • High hip center is an acceptable option for acetabular reconstruction. • Modular stems like S-ROM are helpful in controlling version. • STSO is indicated in Crowe type 4 dysplasia with >4 cm leg length discrepancy.

References 1. McCarthy JC, Noble PC, Villar RN. Hip joint restoration, worldwide advances in arthroscopy, arthroplasty, osteotomy and joint preservation surgery. Springer; 2017. https://doi.org/10.1007/978-­1-­4614-­0694-­5. 2. Lodhia P, Chandrasekaran S, Gui C, Darwish N, Suarez-Ahedo C, Domb BG. Open and arthroscopic treatment of adult hip dysplasia: a systematic review. Arthroscopy. 2016;32(2):374–83. https://doi. org/10.1016/j.arthro.2015.07.022.

V. C. Bose et al. 3. Bernasek TL, Gustke KA.  CT analysis of 100 Japanese patient with DDH. Philadelphia, PA: Poster session presented at: Biomedical Engineering Society Philadelphia; 2004. 4. Wiberg G. Studies on dysplastic acetabula and congenital subluxation of the hip joint: with special reference to the complication of osteoarthritis. Acta Chir Scand. 1939;83(Suppl 58):1–135. 5. Shah A, Kay J, Memon M, et al. Clinical and radiographic predictors of failed hip arthroscopy in the management of dysplasia: a systematic review and proposal for classification. Knee Surg Sports Traumatol Arthrosc. 2019;28:1296. https://doi. org/10.1007/s00167-­019-­05416-­3. 6. Kraeutler MJ, Goodrich JA, Ashwell ZR, Garabekyan T, Jesse MK, Mei-Dan O.  Combined lateral osseolabral coverage is normal in hips with acetabular dysplasia. Arthroscopy. 2019;35(3):800–6. 7. Crowe JF, Mani VJ, Ranawat CS. Total hip replacement in congenital dislocation and dysplasia of the hip. J Bone Joint Surg Am. 1979;61(1):15–23. 8. Yang Y, Zuo J, Liu T, Xiao J, Liu S, Gao Z. Morphological analysis of true acetabulum in hip dysplasia (Crowe Classes I–IV) via 3-D implantation simulation. J Bone Joint Surg Am. 2017;99:e92. 9. Shi X, Li C, Cheng C, Feng C, Li S, Liu J. Preoperative planning for total hip arthroplasty for neglected developmental dysplasia of the hip. Orthop Surg. 2019;11(3):348–55. https://doi.org/10.1111/os.12472. 10. Delp SL, Wixson RL, Komattu AV, et al. How superior placement of the joint center in hip arthroplasty affects the abductor muscles. Clin Orthop Relat Res. 1996;328:137–46. 11. Dearborn JT, Harris WH. High placement of an acetabular component inserted without cement in a revision total hip arthroplasty. Results after a mean of ten years. J Bone Joint Surg Am. 1999;81:469–80. 12. Nawabi DH, Meftah M, Nam D, et al. Durable fixation achieved with medialized, high-hip center cementless THAs for Crowe II and III dysplasia. Clin Orthop Relat Res. 2014;472:630–6. 13. Kaneuji A, Sugimori T, Ichiseki T, et  al. Minimum ten-year results of a porous acetabular component for Crowe I to III hip dysplasia using an elevated hip center. J Arthroplast. 2009;24:187–94. 14. Murayama T, Ohnishi H, Okabe S, et al. 15-year comparison of cementless total hip arthroplasty with anatomical or high cup placement for Crowe I to III hip dysplasia. Orthopedics. 2012;35:e313–8. 15. Krych AJ, Howard JL, Trousdale RT, Cabanela ME, Berry DJ.  Total hip arthroplasty with shorthening subtrochanteric osteotomy in Crowe type-IV developmental dysplasia: surgical technique. J Bone Joint Surg Am. 2009;91(9):2213–21. 16. Liu R, Li Y, Fan L, Mu M, Wang K, Song W. Depression and anxiety before and after limb length discrepancy correction in patients with unilateral developmental dysplasia of the hip. J Psychosom Res. 2015;79:574–9. 17. Pagnano W, Hanssen AD, Lewallen DG, Shaughnessy WJ. The effect of superior placement of the acetabular component on the rate of loosening after total hip arthroplasty. J Bone Joint Surg Am. 1996;78(7):1004–14.

Hip Arthroplasty for Inter-­Trochanteric Fractures in Elderly

18

Rajeev Joshi, Dheeraj Attarde, and Sahil Sanghavi

18.1 Introduction Intertrochanteric fractures in the elderly are common, and most of them are well managed with fixation by the proximal femoral nailing devices. Factors that play a role in decision making for choosing the surgical line of management, i.e., osteosynthesis vs arthroplasty, include—fracture location, anatomy (stable/ unstable), physiological age (activities of daily living/ambulatory status/comorbidities), and bone stock [1]. Stable fractures can be treated reliably with internal fixation. However, unstable fractures in the elderly present a difficult scenario due to the deficient bone stock and osteoporosis, which can predispose to complications of internal fixation like perforation or screw cut-out. In addition, prolonged immobilization or restricted mobilization, which may be required after internal fixation, can predispose patients to pressure sores, respiratory tract infections, atelectasis, deep vein thrombosis and so on. The failure rates of internal fixation devices can range from 8% to 12%. In

addition, the chances of screw cut out and collapse of fragments or implant back out are more in elderly patients due to osteoporotic bone [1]. Indications for hip arthroplasty in inter-­ trochanteric fractures include—(a) fresh fractures—unstable fractures in elderly patients or pre-existing arthritis and (b) non-union or mal-­ union of inter-trochanteric fractures. If arthritis is present, then total hip arthroplasty (THA) should be done; if not, then hemiarthroplasty can be done [3]. For cases with failed inter-trochanteric fractures, the surgical options are either to opt for revision osteosynthesis or hip arthroplasty. For older patients, especially those with osteoporotic bone and pre-existing arthritis, hip arthroplasty is a better option for revision surgery. Hip arthroplasty in these cases is technically demanding due to issues such as assessing version, achieving limb length equalization, and preventing varus collapse in comminuted fractures [3]. The majority of these cases do well with hemiarthroplasty like a bipolar, and sometimes, a THA is done if the inherent walking ability of the patient is quite appreciable.

R. Joshi · D. Attarde · S. Sanghavi (*) Sancheti Institute for Orthopaedics and Rehabilitation, Pune, India © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_18

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The goals of treatment are immediate pain relief, early ambulation, and rehabilitation to expedite return to pre-fall ambulatory status and activities of daily living [1]. The survival rate at 1 year correlates directly to the patient’s ability to regain pre-fall ambulatory level. This further stresses the need to allow early mobilization to prevent cardio-pulmonary complications, pressure sores, or thrombosis and full weight bearing as elderly patients often find it difficult to cooperate with partial weight bearing that may be required after internal fixation [2].

18.2 Hip Arthroplasty in Fresh Cases of IT Fracture In elderly patients above 75  years of age, the treatment of IT fractures is osteosynthesis as a first choice, and the use of intramedullary devices like PFNA 2 has reduced the requirement for arthroplasty. However, in cases of the fracture being comminuted with the blowout seen in the lateral wall of the trochanter and the posterior wall of the GT, our preference is to perform arthroplasty in such cases. Rarely, an arthritic hip will also have an IT fracture requiring total hip arthroplasty. As compared to hemiarthroplasty, total hip arthroplasty for traumatic indications has the advantage of better functional outcomes and lower reoperation rates, but the rates of dislocation are higher. This instability after THA can be due to various factors such as approach, head size, inappropriate restoration of offset /biomechanics, trochanteric, or abductor-related issues, cognitive dysfunction, and insufficient muscular stability or neuromuscular disease. In patients with cognitive dysfunction or those at a high risk for dislocation, one can consider the use of elevated or constrained liners, dual mobility, and larger head diameters wherever acetabular size permits. Reattachment of the trochanteric fragment is absolutely essential to achieve stability and reduce the risk of dislocation. Calcar replacing stems, fully coated stems, or modular stems can be considered for cases with loss of proximal

bone stock [1]. Calcar fractures or comminution can cause bone loss and instability for the prosthesis. Medial calcar augmentation with bone grafting helps in such cases to improve the stability of the stem and avoid varus collapse [3]. Modular implants offer the advantage of separate preparation for the proximal and distal femur to optimize the fit of the prosthesis. Modular stems can also be individualized to adjust the offset/version and limb length discrepancy [4]. While arthroplasty eliminates the issues of internal fixation such as malunion or non-union, screw cut-out, or avascular necrosis, it is still a technically demanding surgery. Before cementing the stem, all fragments must be re-attached to prevent the extrusion of cement. In comminuted fractures, distorted anatomy of the proximal femur can predispose to errors in version and limb length [2, 5].

18.2.1 Preoperative Planning and Fitness Patients undergo routine pre-operative evaluation for surgical fitness. It is important to understand the cognitive competence in all these cases as they will have to follow a guideline, especially in the immediate post-operative period for the containment of the prosthesis and a good result. During the surgery, most of these cases will not be done under hypotensive anesthesia as it would increase their risk, and some bleeding during this procedure is expected. Judicious use of cautery is recommended as these pin point bleeders stay open for a longer time in patients with atherosclerosis; the mouth of the bleeders takes longer time to collapse and seal. For most of these elderly patients, the prosthesis will be a modular bipolar, and in arthritic cases, a THA metal-on-poly or ceramic-onpoly bearing is chosen as per the estimated longevity of the patient, economics, and activity levels. The choice of the modular implant will give a better result by allowing the changes in the

18  Hip Arthroplasty for Inter-Trochanteric Fractures in Elderly

inner head length sizes to equalize the limb length. The choice of fixation will be a cemented implant unless the bone stock is good enough for an uncemented distally secured fixation implant like a Wagner cone stem. In most cases, the lesser trochanter is broken or absent and not available as a marker for the limb length calculation. To address this issue, two simple tricks can be used: 1. Look for the center of the femoral head in reference to the tip of the GT on the normal side and reconstruct on the operative side similarly. 2. Take the proximal portion of the fracture of the calcar area and reconstruct it and then a

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measure the distance from the tip of the GT to the calcar area on the normal side. The best way is to do a trial reduction of the prosthesis with its trial implants on the table and check the limb length. Between lengthening and a mild shortening, we prefer shortening in partial hip replacements and about 5 mm lengthening in total hip replacement cases.

18.2.2 Operative Steps (These have been additionally outlined in Fig. 18.1, 18.2, 18.3,18.4, 18.5, 18.6, 18.7, 18.8, 18.9, 18.10, 18.11, 18.12, 18.13, 18.14, 18.15, 18.16, 18.17, 18.18, 18.19, and 18.20). b

Fig. 18.1 (a, b) The fracture plane is identified

Fig. 18.2  The trochanteric fracture segment is retracted with a broad spike

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Fig. 18.3  Further exploring the interval the head is extracted using a cork screw

Fig. 18.4  A”canal finder” is used to enter the medullary canal and gauge the direction for further broaching of the stem

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Fig. 18.5  Broaching is done with appropriate anteversion

18.2.2.1 Position Lateral decubitus. Routine painting and marking of the skin are done. 18.2.2.2 Incision A lateral incision is taken over the proximal femoral shaft extending proximally, centered on the tip of the GT (approximated using Nelaton’s line).

Fig. 18.6  A thorough wash is given in the medullary canal

18.2.2.3 Deeper Dissection Further dissection is done as a trans-trochanteric approach. The deeper hip joint is approached through the fractured trochanter and not through the muscle planes. This way the trochanter bone pieces are not made devoid of their attachments, and it is also easy to get them together for the final closure, allowing the capsule to be intact and remain as a good support for the stability of the hip joint. Part of the vastus lateralis can be detached from the GT if required for better visualization. The femoral canal preparation is routine, and if a

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Fig. 18.7  Entry hole is made through the lesser trochanter for the wires to be used for tension band wiring

major posterior defect is there, the cut portion from the neck of the femur could be used for added stability when the prosthesis is being inserted. However, our preference is for a cemented prosthesis even if a good fit is there unless a distal fitting stem like Wagner cone is used. Many of these would have a bowed femur and are not good femora for uncemented long stems. The marrow also is replaced by fat, and with thinned-out cortices, cemented fixation seems to be a better choice in these cases. These are elderly patients with limited mobility, and hence, uncemented prostheses with long stems would give similar utility as a cemented stem. Once the desired prosthesis is inserted and the final reduction is done, the capsule in the superior aspect is closed, and thereafter, the trochanteric pieces are brought together by using Vicryl no 2 and taking multiple sutures through the bones as

Fig. 18.8  Wires are passed through the lesser trochanter

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Fig. 18.9  A cement restrictor is inserted into the femoral medullary canal to the appropriate depth after measuring the length of the stem

the bones are soft and the needle of the no 2 Vicryl strong enough to pierce it. Avoid using bone wires that break in time, and a bursa tends to form around the tips, which is bothersome for the patient, and the patient is apprehensive looking at the x-ray showing broken wires. For those who are more comfortable with non-absorbable sutures, Ethibond no 1 is also a good option, but the number of knots required for a secure fixation is many, giving a bulge in multiple sutured trochanteric pieces. In the post-operative period, an attempt is made to mobilize the patient once the anesthesia wears off. Use of a walking frame is advised for 6 weeks, and thereafter, stick support for assistance may be required. Case Examples: X-rays (Fig. 18.21)

Fig. 18.10  Insert the stem and check if the cement restrictor has reached the desired depth in the canal and is not obstructing the stem placement

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Fig. 18.11  A drain is inserted and a roller gauze soaked in saline/adrenaline is used to pack the medullary canal

Fig. 18.12  A cement gun is used to fill cement in the medullary canal in a retrograde manner

Fig. 18.13  Stem is inserted into the canal

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of intra-operative fractures and cortical perforation. Severe fibrosis in cases of non-union also adds to difficulty in exposure. The screw or the bolt in the head of the femur in many cases would have penetrated the acetabulum and violation of the floor of the acetabulum should be expected during surgery. Because of these issues, it is wiser to do a total hip replacement rather than a partial hip replacement in such cases. In addition, as one surgery has been done, and the implant has backed out or penetrated, there is a risk of low-grade infection, and these joints should be aspirated in the outpatient department under ultrasound guidance to look for the offending organism, and if found, then a two-­ stage procedure must be carried out where in the first stage the infection is eradicated and in the second stage the joint replacement is done. In these cases, the track made by the implant like the DHS or PFNA 2 is not sclerotic and is easily negotiated by the broaching of the femur for cemented or uncemented prosthesis fixation. Fig. 18.14  Vertical offset is measured intra-operatively In cases of trochanteric non-union, the non-­ and compared to the pre-operative templating to decide union site must be mobilized, fibrous tissue is the appropriate head to be used to achieve equal limb then debrided, and high-speed burr can be used to length decorticate the bone. In patients with previous intra-medullary implants, the trochanteric entry-­ point and sclerosis around the implant make it 18.3 Hip Arthroplasty in Old Non-­ difficult to broach the canal. Unions/Failed Fixation of IT The choice of the uncemented stem must take it Fractures into account the fracture pattern and proximal bone stock available. In cases where there is poor These could be divided into cases: or minimal proximal metaphyseal bone available for the stability of the stem, distal fitting stems 1. Early—within 3 months and fully coated stems must be considered. 2. Middle—after 3 months to 1 year ­Modular implants are of particular benefit when 3. Late—after 1 year there is a mismatch between the proximal and Early failures and middle level failures in the distal femoral anatomy. Pachore et  al. opined that even though trointertrochanteric fractures have in common un-­ chanteric union may not be achieved in all united fractures and loss of the bone stock in the proximal femur due to osteoporosis and limited patients, the fixation device provides an intact loading of these bones. In addition to osteopo- soft tissue sleeve continuing from the gluteus rotic bone and poor proximal bone stock, the medius proximally to the vastus lateralis distally. presence of holes after removing the implant, dis- This will also guard against trochanteric escape torted bony anatomy and fibrosis increase the risk and thus provide stability. Abductor lurch and the

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Fig. 18.15  With a wire passer loop, the wires are looped around the lesser trochanter beneath the femur (anterior aspect of the femur) and removed from the lateral aspect of the femur

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Fig. 18.16 The head is then reduced into the acetabulum

need for aids are not uncommon, and additional stability can be achieved by enhanced posterior capsular repair. In comparison to other published results, no dislocations in their series were attributed to the good union rates of the greater trochanter, which, along with posterior capsular closure, is one of the most important determinants of stability in these cases [5]. Remove all the fibrous tissue from the implants and send them for culture. Staph epidermis is the most common ­bacteria seen. For cases where the trochanter has malunited, a trochanteric slide osteotomy may be required to access the femoral canal [4]. During surgery for failed internal fixation of IT fracture, it is better to dislocate the hip first and then remove the implant. The acetabular preparation is done with care as the bones are soft and penetration of the floor is common. Morcellized bone graft can be used on the floor to improve bone stock if required. In choosing the femoral implant choose the stem, which goes 2 cm beyond the last screw hole in the femoral plate system to avoid early stress fractures in the femur. Long stem implants are

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intended to bypass the distal most screw hole by two cortical diameters [6]. Late IT fractures treated with osteosynthesis will have issues of malunion in the varus and limb length shortening. Secondary post-traumatic AVN is seen in some cases and delayed arthritis of the hip joint with loss of range of movement and function in some. Rarely, it will have a fibro-­osseous union with pain and dysfunction of the hip joint. In pre-operative assessment, infection must be ruled out. If the hip is arthritic, then total hip arthroplasty is done. Sclerosis about the tracks of the implant is an issue when putting in the femoral implants, and the track must be broached appropriately, otherwise, smaller stems will be used erroneously and could lead to early loosening of the implant. If the track is not well removed, it could cause a fracture while using the larger broaches for preparing the femoral canal. The best and safe way to remove this bone is by using burrs, and its various sizes should be kept in the operating room for use. The shortening in malunited IT fractures is sometimes difficult to correct as there is extensive fibrous tissue about the proximal femur so extensive dissection may be required or the shortening may have to be accepted if it is within a centimeter. Iatrogenic fractures of the shaft of the femur are common as the older implants are difficult to remove and overzealous sharp instrument use or large hollow mills may predispose to fractures. Adjuvant fixation may be required for this.

18.4 Discussion Geiger et  al. compared the mortality risk and complication rates of osteosynthesis (proximal femoral nail or Dynamic Hip Screw) vs arthroplasty for pertrochanteric fractures. They found no significant difference in mortality rates between the 2 groups. The main complication with replacement was dislocation, which was significantly higher in the primary arthroplasty

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Fig. 18.17  Two K-wires are then drilled into the femur from the tip of the greater trochanter into the proximal femur

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Fig. 18.18  Wire passer loop is then used to loop the wires below the inserted K-wires and gluteus medius

group as compared to hemiarthroplasty [2]. Pachore et al. evaluated their results in 30 patients with arthroplasty for failed internal fixation of intertrochanteric fractures. Of these 30 patients, 16 had nonunion of the greater trochanter, which was fixed by using tension band wiring. There was no dislocation in their series. They attributed a lower dislocation rate in their study as compared to the literature to good union rates of fixation of the greater trochanter, which was one of the most important determinants of stability in these patients along with the meticulous closure of the posterior capsule [5]. Thakur et al. evaluated 15 patients operated with arthroplasty for failed trochanteric fracture fixation using a tapered, fluted, modular, distally fitting cementless stem. They found a statistically significant difference in the Harris hip score post-operatively with no dislocation in their series. About 14/15 stems had stable bony ongrowth, whereas 1

patient had stable fibrous ongrowth, which was due to an undersized implant and subsidence [7]. Pal et  al. conducted a prospective study on 18 cases of unstable intertrochanteric fractures (12—hemiarthroplasty and 6—total hip arthroplasty) with an average follow-up of 12 months. Of the 18 patients, 7 had shortening of the operated limb (managed with a shoe raise), whereas 3 had lengthening of the operated limb. All patients had clinically significant functional outcomes as assessed by the Harris hip score and the WOMAC score [3]. Srivastav et  al. retrospectively evaluated 21 total hip arthroplasties done for failed fixation of proximal hip fractures with an average follow-up of 4 years. They had three dislocations in their series and one case of aseptic loosening of the cemented Charnley stem that required revision. The most common cause of residual hip pain was trochanteric nonunion or trochanteric bursitis [8].

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Fig. 18.19  The wires are tensioned in a figure of 8 fashion, and then, the two K wires are bent at 180°

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Fig. 18.20  After bending the K wires, they are turned medially 180 degrees to hook them over the inner cortex of the greater trochanter and are then punched into the bone

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Fig. 18.21 (a) X-ray showing pertrochanteric fracture with a greater trochanteric fracture on the left side. Right side—previously operated hemiarthroplasty with tension

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band wiring for greater trochanter. (b) Post-operative x-ray showing left side hemiarthroplasty with greater trochanteric tension band wiring with the double wire loop

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18.5 Summary Hip arthroplasty is a technically demanding procedure for these patients as compared to other indications of hip arthroplasty. As compared to hemiarthroplasty, total hip arthroplasty has the advantage of better functional outcomes and lower reoperation rates, but the rates of ­dislocation are higher. Reattachment of the trochanteric fragment is absolutely essential to achieve stability and reduce the risk of dislocation. Arthroplasty is an effective procedure for inter-trochanteric fractures, which are unstable, osteoporotic, or have pre-existing arthritis, and is also a good salvage procedure for failed internal fixation of proximal femur fractures.

References 1. Curtin M, Pomeroy E, Broderick J.  Arthroplasty for proximal femur fracture. In: Total hip replace  - an overview; 2018.

R. Joshi et al. 2. Geiger F, Zimmermann-Stenzel M, Heisel C, Lehner B, Daecke W. Trochanteric fractures in the elderly: the influence of primary hip arthroplasty on 1-year mortality. Arch Orthop Trauma Surg. 2007;127(10):959–66. 3. Pal C, Dinkar K, Mittal V, Goyal A, Singh M, Hussain A.  Role of bipolar hemiarthroplasty and total hip arthroplasty in unstable intertrochanteric fracture femur. J Orthop Allied Sci. 2016;4(2):69. 4. Liu P, Jin D, Zhang C, Gao Y.  Revision surgery due to failed internal fixation of intertrochanteric femoral fracture: current state-of-the-art. BMC Musculoskelet Disord. 2020;21(1):1–8. 5. Pachore JA, Shah VI, Sheth AN, Shah KP, Marothi DP, Puri R. Hip arthroplasty in failed intertrochanteric fractures in elderly. Indian J Orthop. 2013;47(6):572–7. 6. Petrie J, Sassoon A, Haidukewych GJ. When femoral fracture fixation fails: salvage options. Bone Joint J. 2013;95-B(11):7–10. 7. Thakur RR, Deshmukh AJ, Goyal A, Ranawat AS, Rasquinha VJ, Rodriguez JA.  Management of failed trochanteric fracture fixation with cementless modular hip arthroplasty using a distally fixing stem. J Arthroplast. 2011;26(3):398–403. https://doi. org/10.1016/j.arth.2010.01.103. 8. Srivastav S, Mittal V, Agarwal S.  Total hip arthroplasty following failed fixation of proximal hip fractures. Indian J Orthop. 2008;42(3):279–86. https://doi. org/10.4103/0019-­5413.41851.

Total Hip Arthroplasty in Ankylosed/Fused Hips

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Pradeep B. Bhosale, Pravin Uttam Jadhav, and Vijaysing Shankar Chandele

19.1 Introduction Ankylosis of the joint is defined as the total loss of joint movements. Hip ankylosis may follow several hip pathologies, such as inflammatory arthropathies, particularly ankylosing spondylitis (AS), sequelae of septic hip infection, including tuberculosis and post-traumatic cases [1]. Among patients with ankylosing spondylitis (AS), it has been estimated that 50–90% have bilateral hip involvement [2]. Surgical arthrodesis has also been used in the past to treat end-stage hip disease. This was especially recommended for monoarticular disease in younger patients to provide pain relief with excellent stability at the expense of motion [3]. While a bony fusion in functional position can provide long-term results comparing favourably with those of arthroplasty [4], however poorly positioned hip fusion can lead to poor functional outcomes and affect daily living activities [5]. Long-term hip fusion alters

P. B. Bhosale (*) · P. U. Jadhav · V. S. Chandele Nanavati Max Super Speciality Hospital, Mumbai, India Maharashtra University of Health Sciences (MUHS), Nashik, India

the biomechanics of the adjacent joints, including the lumbosacral spine and ipsilateral knee, as well as the contralateral hip and knee. Gore et al. [6] evaluated the walking patterns of men with unilateral hip fusions. They found that absent hip motion is compensated for by increased transverse and sagittal rotation of the pelvis, increased motion of the contralateral hip and increased flexion of the knee throughout the stance phase on the fused side. These findings correlate with the clinical degenerative changes seen in long-­ term studies by Callahan et  al. [3]. Sponseller et al. [7] have reported that most commonly the related pain was in the lower back, ipsilateral knee and contralateral hip. Several decades after the ankylosis, this may result in increased pain and decreased functional capacity [2, 3]. Many patients may request the takedown of their fusion, hoping to improve gait and function and relieve pain from adjacent joints [4, 8]. Excision arthroplasty is considered more of a salvage option since it produces significant hip instability, which may be painful sometimes. Conversion THA has been reported to effectively relieve or eliminate these symptoms, thereby improving overall patient function and satisfaction. However, the conversion arthroplasty is not an easy, straightforward surgery; it is technically demanding and is associated with a high complication rate. Meticulous preoperative planning and an extensive surgical experience to perform complex primary and revision arthroplasty surgeries are mandatory for a good surgical result.

© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_19

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19.2 Pre-Operative Evaluation 19.2.1 Pre-op Optimisation Cases with ankylosing spondylitis have multisystem involvement. Anti-TFN-alpha agents used in these cases are associated with increased wound breakdown. These need to be stopped along with the consultation of a rheumatologist.

19.2.2 Decision About Operating Both Hips Simultaneously or Sequentially in Cases of Bilateral Hip Involvement

19.2.3 Preop Planning

19.2.2.1 Advantages of Single-Stage Bilateral THA • Single verses double anaesthesia. • Early rehabilitation. • Ambulation better and safe. • Eliminates mechanical stress on operated THA. If both hips are ankylosed in a deformed position, unless each hip fusion is not taken down there is extra strain on the THA, and may become loose as shown in the example Fig.  19.1. Hence, unless both hips are in a functional mobile position, ambulation is not effective and safe. • Hospital stays 40% less. • Overall cost less. a

If the medical condition of the patient permits only a unilateral operation even in bilateral ankylosis, the hip with the abduction deformity should be given priority. The abducted limbs can be kept on the pillow as shown in Fig.  19.2a. Even in bilateral fused hips when single-stage bilateral THA conversion is decided, the more abducted side usually gets first surgery preference [9], bilateral synchronous THA was effective for bony ankylosis of the hip in patients with AS because it improved patients’ quality of life and had satisfactory mid-term outcomes.

b

Fig. 19.1  A case of Ankylosing spondylitis with bilateral ankylosed hips treated with only Lt THA (a) Lt THA aseptic loosening of cup with dislocation after 3  years while Rt hip fused (b) Lt THA revised using cemented

1. In cases of surgical fusion done in childhood, the anatomy is distorted, the leg length discrepancy is present, and the sciatic nerve is shortened and adherent [10]. 2. The position of any internal fixation implants needs to be accurately established and the surgical incision needs to be planned accordingly. Equipment that might be required to extract the old implant used for fixation of arthrodesis or prior surgery need to be arranged.

19.2.4 Radiological Evaluation 1. Approx. implant size 2. Assessment of Deformity in fused position c

implants while Rt THA done using cementless ceramic on cross linked poly implants THA and (c) patient pain free functional after 15 years post-op

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Fig. 19.2 (a) Continuous epidural anaesthesia catheter, lateral patient position with fused Rt hip in 60° abduction deformity and (b) after draping with adjusting position using sterile thick mobile pillow support

3. Implant size and placement 4. Pelvic inclination measurements 5. Limb length assessment 6. Restoration of offsets – Accurate reconstruction of the offsets gives the previously weak abductor musculature due to disuse, the best chance of strengthening after restoration of mobility

19.2.5 Limb Length Discrepancy Functional limb length must be calculated for limb length equalisation. Correction of limb length discrepancy is important for patient satisfaction. In the presence of fixed pelvic obliquity, there is discrepancy between true and functional limb lengths [11]. When there is no future surgical correction anticipated for any pre-existent spinal deformity, the takedown of ankylosed hips can be performed safely otherwise spinal correction may alter hip position resulting in a limb length discrepancy due to possible pelvic obliquity and a change of acetabular version leading to dislocation. True length and functional length assessments should be done pre-operatively, especially when the spine is stiff. Decision needs to be made about how much limb length discrepancy can be corrected without compromising the neurovascular status of the limb. Calculate functional and true length measurements with implant position planning and execution during pre-op and intra-op measurements. Limb length correction should be limited as the sciatic nerve may get stretched. The maximum length that can be safely gained at the time of THR is no more than 4 cm [12, 13].

19.3 Surgical Considerations 19.3.1 Anaesthesia (Fig. 19.3) A decrease in tidal volume due to decreased chest expansion is a negative prognostic factor for general anaesthesia and intubation. Pulmonary function tests should be done before the procedure. ECG and echocardiography need to be done preoperatively as there is a high incidence of A-V block or right bundle branch block (RBBB) [14]. In Ankylosing Spondylitis cervical spine is usually ankylosed as shown in Fig 19.3a, hence intubation for endotracheal tube insertion for general anaesthesia is difficult. Hence endoscopic endotracheal intubation as shown in Fig 19.3b is advised which is safe and less traumatic for giving general anaesthesia.

19.3.2 Positioning of Patient for THA Surgery Patients with bilateral ankylosis with deformities in AS may have a problem with positioning for THA. Supine position is easy; however, THA in a bony fused hip may be difficult. Ankylosis of the contralateral hip can be an obstacle to proper positioning of the pelvis, which is essential for performing THA, especially in the lateral position. Deformities occur in various positions of the hip. External rotational, abduction and flexion deformities are the most commonly seen in ankylosing spondylitis. It alters the pelvic position while performing THA. Spinopelvic altered alignment affects the version and inclination of

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b

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Fig. 19.3 (a) X-ray showing complete fusion of cervical spine and (b) endoscopic nasal fibre-optic nasotracheal intubation Fig. 19.4 Lateral position pelvic stabilisation (a) Support clamps 1. Pubic Symphysis 2. Sacrum (b) Lateral position with a stable pelvis for THA with gel padding for the opposite knee and leg

b

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the socket, with the possibility of malpositioning of the socket. We prefer a stable lateral decubitus position with anterior pubic and posterior sacral supports as shown in Fig. 19.4. In patients with windswept (one side abduction while the other side adduction) deformities, we operate the abduction deformity first as shown in Fig 19.2b.

19.3.3 Surgical Approaches Basic principles to convert a bony fused hip to THA: • No dislocation is possible due to ankylosis of the hip. Hence, we need a safe, complete neck

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resection and adequate exposure for the correct position and stable implantation. • Preservation of abductors. • Release of all contracted soft tissue to achieve optimum soft tissue balance. Exposure of the hip in ankylosing spondylitis is difficult as the majority of deformities are in abduction, external rotation and flexion. The posterior capsule and external rotators are contracted. Consider an approach that spares abductors that are already weakened due to chronic disuse. Various approaches to hips that are commonly used in cases of fused hips are as follows.

19.3.3.1 Trans-Trochanteric Approach This approach involves a trochanteric osteotomy with retraction of the entire Gluteus Medius and Minimus reflected superiorly to gain access to the hip joint. Advantages • Excellent 360° exposure of hip. • It preserves the already scarred and weak abductors. • In cases of previous surgical arthrodesis, the greater trochanter might be over the axis of entry of the femoral component into the medullary canal. The trans-trochanteric approach facilitates femoral entry in such difficult scenarios. • Using this approach, trochanteric advancement can be carried out. Trochanteric advancement is needed in such cases to adjust the tension of the abductors for better stability and function. Disadvantage • There is a risk of trochanteric non-union with this approach. • Painful trochanteric bursitis due to prominence, breakage of wires, etc. • Higher incidence of heterotrophic bone formation. • Hardware problems due to breakage or protrusion, etc.

19.3.3.2 Posterior Approach Posterior approach is more popular for THA. It is very useful in the presence of an adduction defor-

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mity. In an externally rotated extremity, the sciatic nerve is very close to the neck-posterior acetabular wall junction, and exposure to the posterior aspect of the neck is limited. Overzealous retraction during exposure and while taking the neck cut may cause inadvertent injury to the sciatic nerve and damage to the anterior acetabular wall. It is difficult to perform a safe neck resection.

19.3.3.3 Anterior Approach Anterior approach is very easy in the presence of external rotation deformity and difficult in the presence of adduction deformity. The supine position is useful in external rotation deformities. However, this approach requires femur retraction, which is risky in osteopenic bones. Also, it is not possible to release the contracted posterior capsule and external rotators from the anterior approach effectively. Femoral implantation may be difficult if there is an associated flexion deformity of the knee. 19.3.3.4 Lateral Approach This approach involves the detachment of the anterior one-third of the Gluteus Medius. Glutei are already wasted in cases of fused hips. Thus, this approach may weaken already wasted abductors and increase the chances of a persistence of limp post-operatively. In addition, this approach is associated with a risk of superior gluteal nerve injuries. 19.3.3.5 Dual Approach to Hip (Bhosale’s Approach by Sr. Author) This approach combines both anterior and posterior hip approaches using a single skin incision. Selectively useful in cases of hip fusion with abduction-external rotation deformity as shown in Fig. 19.5. We have been using this special approach selectively with external rotation deformities in taking down fused hips using a single incision dual anterior and posterior approach in 78 bony fused hips since 1991 (past 29  years). This permits a ‘safe neck resection’ and ‘glutei-sparing’ approach. The approach has been perfected on cadavers before its practical use. The approach gives excellent anterior hip exposure in the presence of external rotation deformity, and permits safe neck resection under direct vision and after

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a

b

c

Fig. 19.5 (a) Anterior dissection exposing the neck first spike superiorly under the capsule with Glut Med/Min, second spike medially subperiosteally over the medial acetabu-

lum under capsule and third spike inferiorly under the capsule and neck. (b) Intact glut. Medius (c) Posterior 360° exposure of acetabulum and transverse acetabular ligament (TAL)

neck resection permits easy mobility of the hip to access posterior exposure to perform THA along with the release of contracted external rotators and contracted posterior capsules safely and as required for effective soft tissue balancing. The surgical skin incision is a standard posterior curvilinear vertical incision centred over the greater trochanter, around 10–15 cm in length. The tensor fascia lata is cut and retracted anteriorly and posteriorly so as to gain a generous exposure. The anterior part of the exposure has commenced. The anterior inferior margin of the Gluteus Medius is identified and separated from the Vastus Muscle inferiorly. Dissection is carried further exposing the anterior capsule. A blunt Hohmann spike was put over the capsule under Glut. Medius and Minimus superiorly and a similar spike under the Vastus inferiorly to expose the anterior capsule. An inverted T-shaped incision is made from the Greater Trochanter (GT) to the medial aspect after safe dissection. Both Hohmann’s spikes were reinserted over the neck of the femur under the capsule superiorly and inferiorly to expose the neck of the femur with careful dissection. A third blunt Homan is passed under the capsule by safe subperiosteal dissection on the medial aspect of the hip as shown in Fig.  19.5a. The entire neck and bony fused hip mass are under direct vision. Under direct vision, a safe neck resection is done using a saw confirming complete resection. An additional 4 mm thick parallel neck segment “napkin ring” may be resected to permit free movement of the femur. An osteotome may be used to confirm complete resection with mobility on distracting the osteotomy. Once

the osteotomy is complete, the femur is free to rotate. Now anterior exposure is complete. We can see complete preservation of Glut. Medius in Fig.  19.5b. Through the same incision with leg mobility, it is possible to flex the knee 90° and internal rotation to gradually dissect posteriorly for conventional posterior exposure. The gluteus maximus tendon insertion at the femur is resected partly to allow better anterior retraction of the femur to expose the acetabulum and minimise pressure on the sciatic nerve. Two-headed pins are passed superiorly in the supraacetabular ilium and posteriorly in ischium for better retraction and safe 360° exposure of the acetabulum. A blunt Hohmann’s spike is placed inferior to the transverse acetabular ligament (TAL) to complete acetabular exposure with a resected head of the femur. We can have a complete visual and tactile feel of the resected neck with the head in 360°. Identification of the true acetabulum starts with the debulking of the residual neck and head of the femur.

19.3.4 Identification of the True Acetabulum Identification of the true acetabulum in case of bony ankylosis is difficult. The following anatomical landmarks are helpful to locate the true acetabulum. Start debulking of the bone and careful reaming after following landmarks: 1. Follow cut neck margins. 2. Acetabular labrum.

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3. Fat pad in pulvinar as shown in Fig 19.7— Even in bony fused hip there is a fat pad in fovea and remnants of ligamentum teres. 4. Checking the depth of the medial wall, using a 1.5 mm drill hole with a depth gauge helps in determining the depth of the medial bone stock of the acetabulum and avoiding excessive removal of subchondral bone.

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5. Transverse acetabular ligament (TAL) is always present, sometimes covered with bone or soft tissue; hence, needs careful dissection for exposure and preservation of the TAL. Act as a guide for anteversion and inclination Fig. 19.5c. 6. Intra-op radiography may be needed sometimes if any difficulty in the location of true acetabular landmarks Figs. 19.6 and 19.7.

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Fig. 19.6 (a) Pre-op Bil. fused hips (b) Planned box neck osteotomy as marked (c) Bilateral cementless THA

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19.3.5 Completion of THA Implantation After trial implantation with confirming stability, impingement-free mobility, limb length equalisation, biomechanical placement and soft tissue balance final implantation may be done. Always reconfirm all the parameters done after final implantation (Fig. 19.8). In stiff spines due to pelvic tilt and obliquity, normal extra-articular mechanical guides with reference to horizontal and vertical parameters may be inappropriate for accurate cup placement. It is always better to use anatomical landmarks for the correct placement of the cup. Transverse acetabular ligament (TAL) and McCollum’s imaginary line can be used as a guide for the accurate direction of reaming and proper placement of the acetabular socket (Figs. 19.9 and 19.10). We prefer to use TAL as one of the best anatomical landmarks for the reaming of the acetabulum and the position of the cup. Ideally, the inferior margin of the cup should be placed parallel to the TAL for anatomical anteversion. Another parameter for reaming

Fig. 19.7  Fat pad in the pulvinar helps in the identification of the acetabulum floor

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b

Fig. 19.8 (a) PBH X-ray showing Bil. abduction deformity. (b) Bil cementless THA

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Fig. 19.9 Implant placement using intraarticular anatomical landmarks helps in the proper positioning of implants, irrespective of pelvis position and deformity. Orienting the acetabulum along the transverse acetabular ligament (TAL) gives the anatomical version and inclination

Fig. 19.10 McCollum’s line. Perpendicular line to imaginary line joining ASIS and greater sciatic notch. This line gives appropriate acetabular cup anteversion independent of pelvis position

the acetabulum in 45° inclination is guided by McCollum’s imaginary line (Fig.  19.10) from the sciatic notch to Ant. Sup. Iliac spine (ASIS) and the reaming direction is approx. 90° to McCollum’s line. For a hip without any pelvic obliquity, the inferior margin of the acetabular cup should lie just medial to the TAL to give approx. 45° inclination. Orienting the acetabular inferior margin of the cup parallel to TAL gives anatomical anteversion. If the socket is too deep and medial to TAL, suggested inclination is less than 45°, while the socket inferior margin projecting laterally outside TAL suggests a cup inclination of more than 45°.

19.4 Special Issues for Takedown of Fused Hips by THA 19.4.1 Spinopelvic Relation Affecting Cup Anteversion 19.4.1.1 Pelvic Tilt in Sagittal Plane Normally, the pelvis is a mobile structure as shown in Fig. 19.11. It tilts anteriorly with lordosis of the lumbar spine during the standing posture, while in the sitting posture, it tilts posteriorly with kyphosis of the lumbar spine. Sagittal pelvic tilt alters the anteversion of the acetabulum. While in a sitting posture with 90° hip flexion,

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272 Fig. 19.11 Normal spinopelvic relation with change of acetabular version from standing to sitting position is approx. 16°. (a) Standing position Acetabular Version (23°). (b) Sitting on the chair with hip flexed to 90°, Acetabular Version (39°) is contributed by hip flexion (70°) and by posterior pelvic tilt (approx. 20°), in normal spine and hips

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hip mobility contributes approx. 70 degrees of movement, while posterior pelvic tilt contributes approx. 20 degrees. As per Dorr’s calculation, approximately for every 1° of pelvic tilt, there is a change in 0.7° of anteversion effectively. Hence for 20° post tilt approx. 16° of cup anteversion is altered [15, 16]. Hence in a stiff spine with loss of normal lumbar lordosis, the pelvis is already tilted posteriorly both standing and sitting (unbalanced). Hence approx. 16° of anteversion is added to the acetabular version due to the stiff spine. We need to reduce cup anteversion as per the pre-operative spinopelvic calculation appropriately to avoid dislocation. If the spine is lax and hypermobile, demonstrating hyperlordosis on standing, we may need to add extra anteversion than normal during cup placement. Any pre-­existing spinal deformity correction surgery should always be done before THA for better pre-­op prediction of spino-pelvic parameters to avoid malposition of the cup. Inadvertently, a small degree of final cementless cup malposition in version may be compensated by using poly inert with elevated lip liner. After the trial components are put in, the hip should be inspected for anterior and posterior instability. Dual mobility THA helps in compensating minor cup version variation.

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19.4.1.2 Pelvic Tilt in Coronal Plane This influences the inclination of the cup. When there is fixed pelvic obliquity in the coronal plane, cup inclination needs to be decided in pre-op planning. Evaluation of fixed pelvic obliquity may be assessed on correctability of sitting, standing and bending x-rays of the pelvis with the spine on AP view. It is demonstrated in Fig. 19.12. This patient has two issues, firstly severe kyphosis at the dorso-lumbar junction of the spine and bony ankylosis of the Lt hip. As per the protocol, spinal corrective surgery gets priority over takedown of Lt ankylosed hip. Post-­ spinal kyphosis correction with fusion and instrumentation resulted in fixed pelvic obliquity with the left-side pelvis inclining 8° downward in the coronal plane. Hence, while doing THA, the socket position on the Lt side is put in 48° with reference to the anatomical landmark so that while standing functional socket inclination is 40° as shown in Fig. 19.12d while compensation for fixed pelvic obliquity is 8° in the coronal plane. 19.4.1.3 Pseudo Kyphosis It has been identified as a functional attitude while standing with forward bending of the trunk. On detailed evaluation, it was found that there is bilateral ankylosed hips with 70 degree flexion of the hips as shown in Fig.  19.13 and there is no kyphotic deformity of the dorso-­

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Fig. 19.12 (a) PBH x-ray showing LT hip bony fusion in a case of healed tuberculosis (T.B.) hip. (b) Spinal kyphotic deformity post T.B. corrected surgically with implant stabilisation and fusion. (c) Preop planning to select cup incli-

nation for functional position to compensate 8° of pelvic obliquity. (d) Demonstrating functional position of 40° inclination by 48° anatomical cup position E. Correction of deformity with good hip function at 8 years post op

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Fig. 19.13  Pseudo kyphosis in patient with ankylosing spondylitis with Bil. fixed flexion deformity of 70 degrees at the hips. (a) Pre-op Bilateral bony fused hips with obliteration of obturator foramen due to 90°. fixed flexion

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deformity, (b) Pre-op deformity like kyphosis (pseudo kyphosis) with no spinal deformity and (c) Flexion deformity corrected during bilateral single-­ stage THA. (d) Good function at 18 years post op

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lumbar spine. After effective bilateral THA with the release of contracted soft tissue, the patient can get an upright position on standing with the loss of pseudo-kyphotic deformity (Fig 19.13d).

19.4.2 Deformity Correction with Fused Hips Especially in AS, patients present with various positions of deformities of the hip associated with bony ankylosis. There is no hip movement possible; hence, there is no pre-operative role for any traction or surgical release of soft tissue contractures. Predominant contractures occur at the hip capsular and soft tissues around the hip. With good pre-operative planning and release of contracted soft tissues and correct position of THA implantation all patients get good hip mobility with significant improvement in function over a period of time after effective rehabilitation from our personal experience in AS. The commonest deformities in AS associated with bony ankylosed hips are flexion, external rotation and abduction. Adequate soft tissue releases of cona

tracted soft tissues such as. Adductor tenotomy, iliopsoas muscle release and anterior capsulotomy are often required to correct severe contractures [17]. In ankylosing spondylitis in young males with bilateral involvement, since patients are bedridden in the active stage of arthritis, they tend to get an attitude of flexion, abduction and ­external rotation while immobile in supine position, resulting in bony ankylosis in the same position. In our series of 242 THA for bony fused hips in 146 patients from 1989 to 2020 (30 years), ankylosing spondylitis 134 patients (bil. 90 and uni. 44) was the majority with 87% of patients having variable deformity of flexion, abduction and external rotation as shown in Fig. 19.14. In post rheumatoid bony ankylosis the hip may get predominantly severe flexion deformity up to 90° as shown in Fig.  19.15 with bilateral involvement. Flexion deformity can be easily identified on pre-op AP X-ray Fig.  19.15a with the obliteration of obturator foramen. In AS, sometimes along with the spine and hips, even the knee can get bony ankylosis as shown in Fig.  19.16. In AS as aetiology, young males are commonly affected. Usually, THA is c

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Fig. 19.14 Ankylosing spondylitis M 21  years with bilateral bony ankylosed hips with flexion abduction and external rotation deformity (a) Standing (b) Sitting pos-

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ture (c) Preop AP x-rays (d) 8  years. Post-op bilateral cementless THA (e and f) Excellent mobility

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Fig. 19.15  Bilateral fused hips with 90° flexion deformity post rheumatoid arthritis (RA) in 34 years female. (a) RA Preop x-ray showing obliteration of the obturator foramen

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Fig. 19.16  Ankylosing spondylitis with bil. Ankylosis hips and Lt knee ankylosis. (a) PBH showing bilateral ankylosis hips, (b) Pre-op patients position, (c) Bilateral

due to 90° fixed flexion deformity, (b) 17 years PO x-ray metal on metal THA implant (Durom, Zimmer), (c) Lat view, (d) 1 year PO full function, (e) 17 years PO full function

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knee AP & Lat. X-ray showing bony ankylosis Lt knee, (d) Bil cementless THA with COP, (e) Lt rotating hinge TKA and F. Clinical result 7 years PO

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the priority over TKA as it is the proximal joint to maintain the restoration of biomechanical alignment. However, unless THA and TKA are done, it is not possible to effectively ambulate patients who have an association of hip and knee ankylosis in the deformed position.

19.4.3 Poor Bone Quality Bone quality is poor due to disuse osteopenia, resulting in an increased risk of intra-operative fractures. Osteoporosis is prevalent among AS patients, and the following special precautions should be taken during the surgical steps: (1) care is taken during neck resection to avoid osteotomy extension into the wall of the acetabulum or splintering of the calcar inadvertently. (2) Hip movement to be attempted only after complete neck resection osteotomy and release of contracted soft tissues, especially capsule, psoas tendon and direct head of the rectus origin at the supra-acetabular region. Violent movement should be avoided to prevent fractures of the ­femoral shaft. (3) Identify the true acetabulum and preserve the bone stock for future revision. (4) Adequate femoral calcar should be preserved as per pre-op planning. When necessary, prophylactic wiring should be used on the proximal femur during broaching and reaming to avoid splitting of the femur. From our study of 242 THA for fused hips, we concluded that primary stable THA helps to permit early weight bearing, which certainly helps to improve osteoporosis as per biological Wolff’s law, which says that loading on a particular bone improves the bone quality and the bone will remodel itself over a period of time within biomechanical limits.

19.4.4 Implants It is controversial whether cemented or cementless prostheses should be used for fixation in AS patients. In our experience in the treatment of 242 fused hips conversion to THA, we have observed

that in AS osteointegration of cementless implants is favourable with effective osteointegration if the primary press fit is satisfactory with modern implants with good surgical technique. The prosthesis can develop firm fixation and exhibit a longer survivorship. Ankylosing spondylitis patients are young males between 20 and 40 years of age. The bone regeneration ability of young patients is remarkable, especially in AS. Early ambulation and gradual weight bearing on stable implants improve the quality of bone osteointegration, especially observed in our experience and as per Wolf’s law of bone remodelling. Dorr type C femurs are found predominantly in older women with a lower body weight. These femurs have structural and cellular compromises and are less favourable for cementless implant fixation. Cemented prostheses were predominantly used in Dorr’s type C and osteoporotic patients. The studies in the Scandinavian countries’ register show better results for cementless femoral stems both in young and older patients with inflammatory arthritis. In a systematic review of the literature, Zwartele et al. [18] have reported that the overall failure rate ratio (cementless/cemented) for the cup was 0.6 (95% CI: 0.14e2.60) and for the stem 0.71 (95% CI: 0.06e8.55), both favouring cementless fixation in rheumatoid arthritis. Saglam et al. [19] found that patients with Dorr type C are prone to femoral loosening, irrespective of the cemented or uncemented stem used. They also noticed higher rates of acetabular component loosening in cases of heterotopic ossification (HO).

19.4.5 Large Head Size It has been seen that larger head size (32 or 36 mm) reduces the chances of dislocation. Uncemented THA with a large size femoral head equal to or greater than 32  mm provides better stability and good functional outcomes with less dislocation rate in comparison to older studies of literature with a femoral head size less than 32  mm [20]. Head size more than 36 mm is not advised.

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Fig. 19.17  Closure of post. Capsular defect by proximal extension of Quadratus femoris muscle to the posterior part of Glut. Medius muscle

19.4.6 Capsular Closure Especially in posterior exposure with external rotation deformity, there is hardly any capsule left for closure of the hip joint. In such a situation, we have used a special technique for the closure of the hip capsule by creating a soft tissue extension of the Quadratus Femoris muscle, extending superiorly to approximate with the Gluteus Medius posterior muscle fibres to form soft tissue cover for the fibrous capsule formation over the period of time, as shown in Fig. 19.17.

19.5 Post-operative Complications 19.5.1 Heterotrophic Ossification Heterotopic ossification (HO) is noticed in patients with AS undergoing hip arthroplasty, with an incidence of between 9% and 100% [21–27]. Risk factors have been identified: trochanteric osteotomy, pre-op bony ankylosis, residual bone particulate debris during THA, multiple surgeries on the hip and post-operative infection [28]. Brooker’s [29]

scale of I–IV quantifies the severity of HO. Not all patients with radiographic signs of heterotopic ossification will develop symptoms. Kocic et  al. [30] observed a radiological incidence of HO around 47% in their study, while only 11% had clinical symptoms. It was observed that only Brooker grades 3 or 4 were symptomatic. Baba et al. did not use any prophylaxis of HO in their study and noticed 6 out of 31 hips developed Brooker Grade 3 HO [31]. Basic care in THA surgery is to clean and wash out bone particulate debris collected during the mechanical preparation of bone, especially in cementless THA implantation. Bhan et al., Li et al. and Malhotra et al. used prophylactic indomethacin and found no occurrence of HO [32–34]. Non-­steroidal anti-inflammatory drugs (NSAIDs) and peri-operative radiation therapy are commonly used for the prophylaxis of HO. NSAIDs act by inhibiting inflammatory cells that aid in the remodelling and formation of bone, while radiation therapy (linear single dose of 700 centi-gray) target pluripotential mesenchymal cells, thereby reducing the formation of new bone to be given within 48 h after surgery [35, 36]. HO prophylaxis should start within 5  days post op and the duration of therapy has

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ranged from 7 days to 6 weeks in different studies with comparable outcomes [35]. There was no significant difference found between the different types of NSAIDs; Indomethacin, diclofenac or naproxen [37]. While fractures encountered intraoperatively show delayed healing, the integration of cementless components may be negatively influenced by the use of NSAIDs. Hashem et al. observed low rates of post op HO in their study involving ­ post-­ arthroplasty radiotherapy [38]. Complications highlighted in this study included non-union in cases of trochanteric osteotomy and trochanteric bursitis [39]. In general, NSAIDs seem to provide superior results when compared with radiation with the added benefit of analgesia [37, 40]. There is a lack of evidence that all AS patients undergoing total hip arthroplasty should receive HO prophylaxis. However, in patients with a history of HO, multiple surgeries or infection, prophylaxis should be considered in the form of post-operative radiation and NSAIDs.

19.5.2 Nerve Injury Commonest nerves involved are Sciatic, Superior Gluteal, Femoral and Obturator in the same sequence of incidence.

19.5.2.1 Tips to Avoid Nerve Injuries Sciatic Nerve It is more common with posterior exposure. During posterior exposure, whenever there is a protrusion or external rotation deformity of hip in the presence of a fused hip sciatic nerve is closer to the neck of the femur underlying the posterior hip capsule and greater trochanter. It can get damaged during the opening of the hip capsule. Two options are safe to avoid nerve injury, firstly take extreme care to remain subperiosteally along the trochanter and the femoral bone and gradually lateralise the soft tissues to get access to the posterior hip capsule. Just feel the nerve, avoid separation and dissection of the nerve as it may cause direct trauma or damage the blood supply of the nerve. Secondly, prefer anterior exposure to resect the neck as described by Bhosale’s dual hip approach in the section on

surgical approaches (Fig. 19.5). In the presence of external rotation deformity in bony fused hips, it is more difficult to perform neck osteotomy from posterior exposure; however, it is conversely safer and easier to perform from wider anterior neck exposure. In addition, while exposing the hip using the posterior approach, the release of insertion of the Gluteus Maximus tendon at the femoral attachment favours better anterior retraction of the femur and less pressure on the sciatic nerve and helps to prevent sciatic nerve compression. Superior Gluteal Nerve The superior gluteal nerve can get injured during the splitting of Gluteus Medius while exposing the hip by Transgluteal exposure. Care is taken to avoid excessive splitting of Glutei more than 4  cm proximal to the tip of the trochanter. The nerve is transversely located approximately 5 cm proximal to the tip of the greater trochanter. Femoral Nerve Femoral nerve bundles are located lateral to the femoral artery in Scarpa’s anterior femoral triangle. Injury can occur during the dissection of the anterior exposure. Special care is taken to identify and guard it safely during anterior exposure. It can get injured by the retractor spike while exposing the anterior rim of the acetabulum during posterior exposure. It is important to put the anterior acetabular spike in a more proximal and superior location to avoid femoral nerve. Obturator Nerve It is rarely injured. It is located on the medial aspect of the obturator foramen. It can get injured if the obturator artery is injured while inserting an inferior acetabular spike to expose the TAL. Sometimes it may get injured by trying to cauterise a troublesome bleeder in the obturator foramen.

19.5.3 Hip Dislocation Incidence varies from 2% to 4.8% in takedown of the fused hip [41]. Incidence is higher with bilateral involvement. Various factors causing dislo-

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cation include the deformation of the pelvic position leading to the malposition of cup version and inclination. In AS, spinal fusion associated with hip fusion leads to difficulty in accurate pre-­ operative planning of the cup position.

19.5.3.1 Important Tips to Reduce Incidence of Dislocation 1. Calculate the Spinopelvic parameter to measure the change in pelvic slope in lateral x-rays (sagittal plane) of the spine with the pelvis in standing and sitting postures as it impacts change in the acetabular version. 2. Calculate fixed pelvic obliquity to adjust cup inclination in a functional position in the presence of fixed pelvic obliquity in the coronal plane. 3. Use a larger head diameter of 36  mm or at least 32  mm diameter whenever possible. If the smaller diameter of the socket not accommodating even 32 mm head, then dual modality THA may be done. Routine use of dual mobility is not recommended in view of the longevity issue, as many patients are young males in the AS group though dual mobility is the best implant to provide stability. 4. Good pre-operative planning, restoring hip biomechanics as normal as possible, accurate component placement, excellent soft tissue balancing, preventing impingement help to prevent dislocation. 5. Capsular closure is extremely important to avoid instability. In fused hips with contracted soft tissues, many times there is no capsule for closure, in such situation some soft tissue scaffold is created using adjacent muscle extension as shown in Fig.  19.16, which will help as a soft tissue scaffold to form a fibrous capsule.

19.6 Post op Rehabilitation Many fused hip patients have significant disabilities pre-operatively due to severe hip deformities, bilateral hip involvement, bed-ridden status. These patients require gradual supervised intensive specialist physiotherapy to avoid the risk of dislocation, especially in bilateral THA and encourage to gain range of movements of hip.

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Full-weight bearing mobilisation is started early with an exercise regimen targeting weak abductors. The patient will need assistive devices in the early post-op period till adequate muscle strength is achieved. Once mobility and stability are achieved by THA, there is a progressive improvement in muscle function and a gradual correction of deformities over a period of time.

19.7 Outcomes 19.7.1 Pain Relief Conversion of the fused hip to the mobile hip by virtue of THA provides pain relief in the surrounding joints and lumbosacral spine. Amstutz and Sakai [8] reported back pain relief in 15 of their 16 patients treated for conversion THA in ankylosed hips. Their study consisted of 16 patients of which 13 had spontaneous ankylosis. Similarly, Lubahn et al. [40] reported good pain relief in adjacent joints in their series of 18 conversion THAs in 17 patients. This study consisted of 14 hips with prior surgical ankylosis. Improvement was seen in back pain, ipsilateral knee pain and contralateral hip pain. The results of these studies indicate that patients with fused hips can benefit from conversion THA, irrespective of the ethology of fusion. There is a significant benefit of improvement in spinal alignment and biomechanical uniform distribution of load in adjacent joints. Kim et al. [41] reported near complete pain relief in 81 of 86 patients with back pain and 28 of 38 patients with ipsilateral knee pain following conversion THA. However, four of the five patients with residual back pain progressed to subsequent back surgeries, while four of the 10 patients with residual knee pain progressed to total knee arthroplasty. So, while counselling, patients should be explained that pain in the adjacent joints may decrease after conversion THA, but pain relief should not be guaranteed.

19.7.2 Hip Mobility After effective correction of all hip deformities and restoring the biomechanics of the hip muscle

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power and mobility progressively improve over a period of 6–12  weeks. Hence, functional hip scores were recoded after 3–12  months postoperatively for initial baseline scores. It has been observed that patients with spontaneous ankylosis with no mobility of the hip joint, regain muscle activity once mobility is achieved by THA, even after 17 years of ankylosis as per our personal study in 21 fused hips of more than 17 years of ankylosis. In our series, we have observed that even after 17  years duration of bony ankylosis once mobility is achieved by THA, muscle activity improves progressively towards near normal over a period of 3–12 months. Unlike nerve injuries, if there is no nerve recovery within 12  months, the motor units of the muscle get destroyed with no possibility of recovery of muscle function, while in ankylosis with no mobility, the nerve conduction is intact, which maintains the integrity of the functioning of the motor units of the muscles. There are no clear parameters to assess the functioning of gluteal muscles preoperatively. Pre-op MRI, USG, CT scan or EMG gives inadequate information about the functioning of the gluteal muscles. It is very difficult to assess voluntary contractibility by local palpation by hand. However, intra-op pink colour and bulk of the muscle are indicators of a probable better recovery of muscle function post-operatively. Atrophied fibrotic pale appearance and poor bulk of the gluteal muscle are poorer indicators of the functioning of the muscles from our personal experience.

19.7.3 Gait Improvement in gait following conversion THA is unpredictable. Persistent Trendelenburg gait has been associated with insufficient restoration of femoral offset, abductor lever arm and incomplete recovery of the abductor muscles. Lubahn et al. [37] studied 17 patients treated with 18 conversion THAs. At 1  year following conversion THA, eight patients required assistive devices. Schäfer et al. [42] reported positive Trendelenburg

signs in 50% of their patients with the study sample of 15 patients. Kilgus et  al. [43] found hip abductor muscle strength continued to improve for ≥2 years following conversion THA. Benedetti et al. [44] used gait analysis to demonstrate that patients can recover the phasic activity of the Gluteus Medius muscle following conversion THA. They also documented a progressive reduction of pelvic compensation in the coronal and sagittal planes when the hip biomechanics were properly restored with optimal component selection and positioning. There is progressive improvement in muscle strength, joint mobility and gait improvement over a period of 3–12 months. Hence, hip activity and functional score may be delayed untill optimum functional improvement.

19.7.4 Survivorship The aetiology of fused hips and age at the time of conversion THA determine the survival of implants to a large extent. Previous surgical arthrodesis and conversion THA done before the age 50 years are associated with poor outcomes and the need for revision surgeries. Strathy and Fitzgerald [45] reported only one failure in the 20 patients with previous spontaneous ankylosis (5%). In contrast, 20 failures occurred in the 60 THAs performed in patients with a previous surgical arthrodesis (33%). The rate of failure was especially high in patients who had undergone multiple surgeries prior to conversion THA (12 of 18 hips, 67%). The authors suggested that the high failure rate was the result of the altered proximal femoral geometry, which led to suboptimal component positioning and fixation. Peterson et al. [46] reported survival rates of 86% at 5 years and 75% at 10 years following conversion THA. Risk factors for failure were found to be surgical arthrodesis, age 4  cm, difficult primary THA, use of cementless surgical technique, and pre-existing nerve injury or spinal issues [12] [13]. Commonly, few metabolic factors such as recent marked weight loss, uncontrolled diabetes mellitus, nutritional deficiencies {vitamin B12, folate, pyridoxine (B6), and thiamine (B1)} and very rarely, genetic factors like hereditary neuropathy with liability to pressure

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palsies may increase the risk of developing a SN injury. These issues along with a pre-existing neural deficit should be assessed and addressed in the preoperative work-up to prevent, prognosticate, and identify a new-onset deficit.

34.5 Clinical Presentation of Sciatic Nerve Injury SN injury produces motor and sensory manifestations, depending on whether there is a complete or partial sciatic nerve injury. Patients may present with foot drop, gluteal pain radiating down the posterior thigh, and/or paresthesias in the SN distribution. A complete SN injury results in weakness of knee flexion and loss of all movement across ankle and toes. On examination, foot dorsiflexion, eversion (supplied by CPN), and foot planter flexion and inversion (supplied predominantly by PTN) are found to be weak, along with loss of ankle jerk. A sensory loss is usually found along the lateral aspect of knee, lateral calf, sole, and dorsum of foot. It may be accompanied by hip and knee pain along the posterior part of thigh. A complete deficit is usually found only in severe cases with transection of the nerve during surgery. When SN injury is only partial, the patients often present with only foot drop ± a sensory loss at dorsum of the foot and the lateral part of calf that may be difficult to differentiate from an isolated CPN injury at fibular neck in the initial stages. However, one may differentiate by checking for weakness of ankle inversion and toe flexion (supplied by PTN), and knee flexion (supplied by SN). Similarly, a sensory loss beyond lateral calf and dorsum of foot indicates isolated CPN involvement [14]. Lumbosacral plexopathy (another common complication of THA), radiculopathy (especially L5), contralateral anterior cerebral artery infarct may masquerade as SN injury, though certain variances in the clinical features may help differentiating among these etiologies (Fig. 34.3).

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Fig. 34.3  Clinical approach to suspected sciatic neuropathy. SLR: Straight leg raising

34.6 Investigations for Sciatic Nerve Injury In addition to the clinical history and examination findings stated above, electrophysiological testing including nerve conduction studies (NCS) and needle electromyography (EMG) as well as structural and functional nerve imaging remain critically important in the diagnosis, localization, quantification, monitoring the recovery and determining the prognosis of SN injury.

34.6.1 Electrophysiology Abnormalities in neurophysiologic testing are usually delayed, appearing only when WD has set in following a focal SN injury. Hence, NCS should be performed 10–14  days after a suspected nerve injury, whereas EMG signs of denervation, i.e., fibrillation potentials and positive-­sharp-waves, appear after approximately

3  weeks, and EMG signs of renervation, i.e., abnormal motor unit action potentials (MUAPs), develop in another few weeks. The latter represent axonal regeneration and collateral sprouting [8] (Fig. 34.2d). Focal neuropraxic SN injury is difficult to establish neurophysiologically except with a cautious use of proximal studies such as F-wave and H-reflex, where only prolonged latencies may be observed (Fig. 34.4a). Focal SN injury with partial axonal loss, i.e., axonotemesis, on NCS manifests as a reduced amplitude of sensory nerve action potential (SNAP) or compound muscle action potential (CMAP) in both CPN and PTN, when compared with the normative values or the contralateral normal side [14]. Motor amplitudes may reduce further over days to become unobtainable 4–12  days later. An immediate non-­ recordable SNAP or CMAP imply severe distal injury with poor chances of recovery. The EMG localization parallels the clinical approach wherein alternate pathologies such as

34  Management of Sciatic Nerve Palsy After a Total Hip Arthroplasty Fig. 34.4 Nerve conduction studies and electromyography abnormalities in neuropathic disorders. (a) Prolonged F-waves; (b) Spontaneous activity—Fibrillation potentials and positive sharp waves (PSWs); (c) Abnormally large Motor Unit Action Potentials (MUAPs)

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peroneal palsy at fibular neck, lumbosacral plexopathy, and lumbosacral radiculopathy must be carefully excluded (Fig.  34.5). EMG should begin with sampling of muscles innervated by deep and superficial peroneal nerves in the lower leg, followed by tibial, sciatic, and non-sciatic innervated muscles in the thigh with a careful examination of short head of biceps, supplied by the CPN division of SN above the fibular neck. The main muscles innervated by sciatic nerve with their nerve supply are mentioned in the Table 34.1. A reduced recruitment of MUAPs is seen on the interference pattern of the EMG studies; however, the other findings change with the

age of the nerve injury, e.g., increased insertional activity/fibrillation potentials/ positive sharp waves suggesting active denervation (Fig. 34.4b). These acute changes develop within 2 to 6 weeks of axonal injury and may persist for several months, even post clinical recovery. Later, signs of reinnervation, prolonged polyphasic MUAPs with large amplitude are seen that usually corroborate with the degree of functional improvement (Fig. 34.4c). The absence of reinnervation at a follow-up study 3–6 months post-­THA, may suggest poor prognosis for complete recovery. Absence of MUAPs portends the worst prognosis for clinical improvement. Intraoperative motor-

Fig. 34.5  Electromyographic approach to sciatic nerve injury

34  Management of Sciatic Nerve Palsy After a Total Hip Arthroplasty

evoked potential (MEP) testing using the transcutaneous nerve stimulation method showing disappearance or decrease in the amplitude of the waveform at hip joint flexion may alert about a possible immobility of the SN and a need for addition neurolysis of SN. Shifting to the neurophysiology lab, and the procedures themselves can be uncomfortable for the patient. Bedside testing is usually technically challenging because of electrical interference and grounding issues.

34.6.2 Nerve Imaging Imaging the SN using ultrasound (USG) and magnetic resonance imaging (MRI) may assist in accurately establishing the SN injury in the immediate post-THA period. An increase in nerve signal in T2-weighted images is usually seen after 48 h. USG, though technically demanding, can conveniently help to identify the lesion site, assessing nerve continuity, predicting the outcome and indication for surgical intervention (e.g., as in Sunderland grade 5). It may also identify adhesion of sciatic nerve to body structure or entrapment in muscle and to assess recovery post nerve repair/decompression. Common findings on USG include neuroma formation, disorganization of internal fascicular structure, complete nerve transection, and hypoechoic and swollen nerve. Dynamic ultrasound examination can further demonstrate nerve adhesion to surrounding tissue and can show the movement of nerve around bony spicules or in other abrasive environments [15]. Ultrasound has a higher focal resolution for superficial nerves whereas MRI gives a wide field of view and can also visualize deep seated nerves and the findings are not altered by interposed bony structures. When MRI is optimized to image peripheral nervous system, it is referred to as MR neurography (MRN) that may aid in differentiating the nerve roots, the plexus, and the peripheral nerve pathologies. High signal intensity in the nerve fibers, increase in nerve dimension, nerve deformation, or loss of nerve integrity on T2-weighted images may be observed on the nerve MRI, which may prompt an early

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surgical intervention [7]. The risk of heating and displacement of the metallic implant and the susceptibility artifacts in MRI can pose challenge. Recent advances in technology further allow visualization of nerve fascicles also and produce minimum susceptibility artifacts [16].

34.7 Management of Sciatic Nerve Injury After THA The management of SN injury post-THA most importantly include a careful discussion between the surgeon and patient regarding the possible etiology and prognosis. The treatment modality (conservative vs. surgical) and the time of intervention have been found to be guided by the extent of SN involvement and clinical presentation in the immediate post-operative period. The wound site and dressings be inspected to look for any sites of constriction. An urgent surgical exploration is indicated in cases with severe pain, any finding suggestive of hematoma formation, acute nerve palsy after limb lengthening, compression and constriction of nerve by surgical material, and where there is a clear nerve transection [3]. In the absence of pain and where radiology does not show any significant compression on the nerve, the management is mostly conservative. Conservative approach incorporates physiotherapy, joint mobilization, and extended bracing (hip extended and knee flexed) along with a recommended watchful waiting for around 3 months for signs of any clinical or electrophysiological recovery. If evident, then an acceptable functional recovery may be anticipated with a continuation of the same care plan [17]. Tendon transfer, a time-insensitive procedure, is done once maximal spontaneous nerve recovery has been achieved and tissue equilibrium has been established, usually after 18 months. In case of an early tendon transfer, a better approach is an end-­ to-­side transfer with a superior healing potential. The outcome can further be enhanced, up to 3 times, by carrying out nerve repair along with tendon transfer [16]. Post-THA SN palsy responds well to early neurolysis (10 mg/L

Sinus tract that communicates to the joint or visualization of the prosthesis

≥1500

≥3000

≥65%

≥80% Positive immunoassay/lateral flow assay

All cultures negative

Positive culture Single positive culture

≤65%

≥65%

2 positive samples with the same microorganism ≥80%

Negative

≥5 neutrophils in a single HPF

≥5 neutrophils in ≥5 HPFs Presence of visible microorganisms

Others Nuclear imaging

Negative three-phase isotope bone scan

Positive WBC scintigraphy

technique. Total cell count, leucocyte count and also crystal analysis, if indicated, should be undertaken [25]. It is crucial for the samples also to be cultured for aerobic and anaerobic organisms in an endeavour to identify a potential causative agent, which can then allow for tailored antimicrobial treatment [26, 27]. Alpha (α) defensin has been shown to be the most sensitive synovial marker of PJI [28]. The European Bone and Joint Infection Society (EBJIS) has recently formulated a classification system for PJIs which integrates work from groups such as the Musculoskeletal Infection Society (MSIS), the International Consensus on Musculoskeletal Infection (ICM)

and the Infectious Diseases Society of America (IDSA). The classification system considers clinical features, laboratory investigations and imaging. The system separates the possibility of an infection into three categories, ‘unlikely,’ ‘likely,’ and ‘confirmed’ (Table 36.1) [29].

36.2.3 Classification There is controversy around the classification of PJIs with current guidance attempting to group infections as acute or chronic [30]. PJIs can be largely classified into early (24  months post-­ operatively) [31]. Early infections typically present with pain, warmth around the proximal thigh, erythema and a fever and are characteristically caused by very virulent organisms, such as Staphylococcus aureus [32]. Delayed infections generally present with persistent joint pain or with loosening of the prosthesis. Delayed infections are commonly caused by less virulent organisms [32]. Late infections usually present as subacute infections or with the presence of systemic symptoms. These infections commonly instigate from bacteria from the skin, dental, respiratory or urinary systems [33].

36.3 Indications for Single-Stage THA Revision Single-stage revision for PJI of the hip has become more popular in recent years, owing to published studies showing comparable, if not better, outcomes when compared to two-stage revision THA with regard to reinfection rates and functionality [34–36]. Indications include an uncompromised host, an identified pathogen sensitive to available antibiotics and sufficient soft tissue envelope [37–39]. Lange et al. reported, in multicentre study involving 56 patients who underwent single-stage revision THA, a 8.9% re-­ infection rate with a mean follow-up of 4 years [40]. Moreover, the microbiological profile has been shown to play a vital role in dictating the success of single-stage revision THA as polymicrobial infections, gram-negative bacteria and atypical infections conveying inferior outcomes [41, 42]. Despite these conclusions, the ENDO-­ Klinik, a specialised centre where a large number of one-stage revision arthroplasty is achieved, does not take into account these factors as absolute contraindications [43]. Also, although a sinus tract has been associated with worse outcomes, and as a result, considered by some authors an absolute contraindication [44, 45], the ENDO-­ Klinik have published results to suggest a single-­ stage revision THA is the surgical procedure of choice in cases involving a sinus tract [46]. Additionally, Jenny et al. described at 87% infec-

tion eradication rate at 3  years follow-up after single-stage revision for infected total knee arthroplasty (TKA), despite a sinus tract present in 43% of the study cohort [47]. Local and host factors have been shown to determine the outcome of one-stage arthroplasty. Wolf et al. classified their patient cohort according to the McPherson classification, a system established on host and patient factors [48]. This study found that superior results were seen using two-stage over single-stage revision THA in patients that presented with systemic symptoms (95% vs 33% infection eradication) and in patients with local soft tissue and bony compromise (95% vs 0% infection eradication). This study reinforces the importance of patient selection in order to achieve good outcomes ­ using single-stage revision THA to combat PJI.

36.4 Contraindications of Single-­ Stage Revision THA As single-stage revision involves just one procedure, careful patient selection is essential for a successful revision procedure. Oussedik et  al. outlined criteria in their study that contradict the use of single-stage revision THA and this is defined in Table 36.2 [38]. Moreover, they support the use of single-stage revision for patients with healthy soft tissue, identified organisms and sensitivities and in cases with minimal bone loss. Table 36.2 Contradictions to single-stage revision arthroplasty Local factors

Host factors

Organism factors

Significant compromise to soft tissue Significant loss of bone precluding cement reconstruction Peripheral vascular disease Immunosuppression Reinfection Systemic disease Concurrent sepsis Polymicrobial organisms Multi resistant organisms (MRSA) Atypical commensals Unusual resistance profiles Unidentified infective organisms

36  Single-Stage Revision for a Prosthetic Joint Infection After Total Hip Arthroplasty

36.5 Surgical Technique Single-stage revision THA involves the explantation of a prosthesis, aggressive debridement and the reimplantation of a new prosthesis within one surgical procedure. The procedure can be broken down into four stages: (1) preparation, (2) debridement and explantation, (3) irrigation with local antiseptics and (4) reimplantation of a new prosthesis [49]. The preparation stage involves proper positioning of the patient in the lateral decubitus position on the operating table. The pelvis should be fixed and a cushion placed between the legs, allowing the involved leg freely able to move in all planes [46]. The surgical site should be cleared of any hair that may obstruct and interfere with the operative field and a ‘social cleaning’ should be carried out. The skin should be prepped and standard hip draping should be carried out. A posterolateral approach to the hip is recommended as it allows wide access to the acetabulum as well as the femur and this is the preferred approach in our institution for revision THAs. Previous scars or any sinus tracts should be incorporated into the incision if possible.

a

477

The debridement process begins with the excision of the previous scar, incorporating any sinus that is present, and thoroughly excising down to the hip joint capsule [50]. During debridement, multiple deep and superficial tissue and fluid samples should be taken and sent for aerobic, anaerobic and extended cultures [49, 51]. A minimum of 3 samples should be taken [30]. All existing implants and foreign material should be removed and in some cases, special instrumentation may be needed to explant long or cemented femoral stems. Any cement and cement restrictors should be meticulously removed for successful one-stage revision THA [13, 39]. The debridement process must include any necrotic tissue or biofilm that is left after the implants are removed (Fig. 36.2a, b). Following debridement, the wound must be irrigated, using a methodical approach. We recommend a 12 L wash of the whole surgical field with warm 0.9% saline using a low-pressure pulsatile lavage followed by 100 ml of a 50:50 mix of sterile water and 3% hydrogen peroxide and also povidine-iodine [52]. Hydrogen peroxide is used for its chemical debriding properties and povidine-iodine for its bactericidal characteris-

b

Fig. 36.2 (a) Clinical photograph of intraoperative step before removing the infected implant. (b) Clinical photograph of intraoperative step including continuing debridement after implant removal

478

W. Wignadasan et al.

Fig. 36.3  Re-draping and rescrubbing after thorough debridement for the same patient in Fig. 36.2

tics [53]. The wound is then packed with gauze that is soaked with povidine-iodine solution and the skin edges temporarily approximated. The wound is then protected with a sterile drape and a new surgical setup is carried out, which consists of the removal of ‘contaminated’ instruments used in the first stage of the procedure, rescrubbing of the surgeons, redraping of the surgical field and the opening of clean instruments for the second stage of the operation [46, 49]. The second stage of the operation should only begin once the surgeon is satisfied that the field is completely free on infection (Fig. 36.3). The next stage of the procedure is the reimplantation phase. The acetabulum and the femur are prepared for the implantation of the revision prosthesis. The vast majority of our revisions are performed using cementless implants (Fig. 36.4) and we only tend to use cement in cases with significant osteoporotic bone. Antibiotic-impregnated cancellous bone graft can also be used in cases with bone loss [49, 54]. In osteoporotic bone, antibiotic-loaded bone cement can be used for the stem with a cementless acetabular component and tantalum augments for cases with significant bone loss [52, 55, 56]. Antibiotics that are added to the cement should be bactericidal, based on the sensitivities of the organisms cultured pre-­operatively, in the powder form and weigh less than 10% of the total cement powder weight so as to not interfere with the mechanical properties of the cement [16, 52, 57]. Once the new prosthesis has been

Fig. 36.4  Postoperative radiographs showing a newly implanted cementless prosthesis

implanted, the whole surgical field should undergo a further washout. Surgical drains can be inserted at the choice of the surgeon. A careful, water-tight closure should be achieved. Post-operatively, routine rehabilitation should occur and patients should be administered intravenous antibiotics until microbiology results are available. Organismsensitive oral antibiotics can then be initiated for a period of at least 6 weeks, and patients should also have serial blood tests to monitor CRP, ESR and nutritional markers [38, 52, 58]. If there are no suitable oral antibiotics available, patients may have intravenous antibiotics administrated in the community if possible. Antibiotics may continue for a longer period if the surgeon feels that there is not an adequate improvement in infective and inflammatory markers [49]. Further investigation

36  Single-Stage Revision for a Prosthetic Joint Infection After Total Hip Arthroplasty

in the form of image-guided aspiration or open surgery may be warranted if there is any sign of recurrence.

36.6 Advantages of Single-Stage Revision Single-stage revision arthroplasty has become more popular in recent years with studies reporting comparable, if not, superior outcomes compared to two-stage revision procedures [13, 35, 36, 59–61]. There are a number of inherent advantages of single-stage revision THA when compared to the twostage approach. The most fundamental advantage is that the explantation of the old prosthesis and implantation of the new revision prosthesis is performed in one single procedure. Single-stage revision, when performed successfully, has been shown to elude the morbidity related to multiple procedures, whilst also reducing length of hospital stay [46, 62]. As revision surgery for PJI is a financial burden for healthcare systems, with costs much greater than revision for aseptic loosening and for primary THA, greater cost-effectiveness can be achieved with one-stage revision THA compared to ­ two-­ stage revision owing to shorter hospital stays and fewer operations [2, 63]. There has been encouraging outcomes conveyed in the literature on one-stage revision for the treatment of PJI of the hip. In a study involving 50 patients diagnosed with PJI after THA, there was no recurrence of infection in patients who underwent a single-stage revision THA procedure at a mean follow-up of 6.8 years [38]. The same study reported a reinfection rate of 5.1% in patients who underwent a two-stage revision procedure. Furthermore, a literature review of over 1200 single-stage revision arthroplasties from 12 studies found an infection-free rate of 83% at 5 years [64]. Winkler et  al. conducted 37 one-­ stage revision THAs using uncemented prostheses and antibioticloaded allograft for cases with bony defects and found a 92% infection-free rate at 4 years’ followup [54]. Additionally, there have been promising results in the literature using the single-stage approach to treat PJIs that present with a sinus tract. Raut et al. performed 57 single-stage revision

479

THAs in patients with a discharging sinus and found a 86% success rate [50]. Moreover, the Endo-Klinik in Hamburg, a unit that conducts large numbers of revision surgery for PJI, advocate that even in cases with a sinus, one-stage revision is the treatment of choice [46]. Also, the Endo-Klinik do not consider polymicrobial infections and resistant pathogens absolute contraindications for single-­ stage revision and have published good outcomes in such cases [16, 43, 46]. Studies have reported positive patient reported outcome measures (PROMs) after one-stage revision THA. Oussedik et al. found significant differences in Harris hip Scores between patients that underwent single-stage revision THA and two-stage revision THA (87.8 and 75.5, respectively, p = 0.0003) at 5 years [38]. Kuiper et al. described good functional outcomes and high quality of life (QoL) scores at a mean follow-up of 41.3 months in patients that had single-stage revision THA [59]. Furthermore, Wolff et  al. reported in their cohort of 26 patients that had undergone a single-stage revision THA with a minimum follow-up of 10 years a mean improvement in HHS from 46.2 to 78.9 [65]. Infection control was achieved in 96.2% of the study cohort at final follow-up.

36.7 Summary PJIs are a devastating and expensive complication associated with joint arthroplasty surgery. Although a two-stage revision procedure is considered the gold standard treatment for a PJI, single-stage revision is a feasible option that can be performed in selected patients.

References 1. Thakrar RR, Horriat S, Kayani B, Haddad FS.  Indications for a single-stage exchange arthroplasty for chronic prosthetic joint infection: a systematic review. Bone Joint J. 2019;101-B(1_Supple_A):19–24. 2. Bozic KJ, Ries MD. The impact of infection after total hip arthroplasty on hospital and surgeon resource utilization. J Bone Joint Surg Am. 2005;87(8):1746–51.

480 3. Hartzler MA, Li K, Geary MB, Odum SM, Springer BD.  Complications in the treatment of prosthetic joint infection. Bone Joint J. 2020;102-B(6_Supple_A):145–50. 4. Springer BD, Cahue S, Etkin CD, Lewallen DG, McGrory BJ.  Infection burden in total hip and knee arthroplasties: an international registry-based perspective. Arthroplast Today. 2017;3(2):137–40. 5. Lenguerrand E, Whitehouse MR, Beswick AD, Jones SA, Porter ML, Blom AW.  Revision for prosthetic joint infection following hip arthroplasty: Evidence from the National Joint Registry. Bone Joint Res. 2017;6(6):391–8. 6. Ahmed SS, Haddad FS.  Prosthetic joint infection. Bone Joint Res. 2019;8(11):570–2. 7. Kurtz SM, Lau E, Watson H, Schmier JK, Parvizi J.  Economic burden of periprosthetic joint infection in the United States. J Arthroplasty. 2012;27(8 Suppl):61–5.e1. 8. Zmistowski B, Karam JA, Durinka JB, Casper DS, Parvizi J.  Periprosthetic joint infection increases the risk of one-year mortality. J Bone Joint Surg Am. 2013;95(24):2177–84. 9. Ibrahim MS, Raja S, Khan MA, Haddad FS. A multidisciplinary team approach to two-stage revision for the infected hip replacement: a minimum five-year follow-up study. Bone Joint J. 2014;96-B(10):1312–8. 10. Garceau S, Warschawski Y, Dahduli O, Alshaygy I, Wolfstadt J, Backstein D. The effect of patient institutional transfer during the interstage period of two-­ stage treatment for prosthetic knee infection. Bone Joint J. 2019;101-B(9):1087–92. 11. Katz JN, Mahomed NN, Baron JA, Barrett JA, Fossel AH, Creel AH, et  al. Association of hospital and surgeon procedure volume with patient-centered outcomes of total knee replacement in a population-­ based cohort of patients age 65 years and older. Arthritis Rheum. 2007;56(2):568–74. 12. Li C, Renz N, Trampuz A.  Management of periprosthetic joint infection. Hip Pelvis. 2018;30(3): 138–46. 13. Haddad FS, Sukeik M, Alazzawi S.  Is single-stage revision according to a strict protocol effective in treatment of chronic knee arthroplasty infections? Clin Orthop Relat Res. 2015;473(1):8–14. 14. Parkinson RW, Kay PR, Rawal A.  A case for one-­ stage revision in infected total knee arthroplasty? Knee. 2011;18(1):1–4. 15. Kallala RF, Vanhegan IS, Ibrahim MS, Sarmah S, Haddad FS.  Financial analysis of revision knee surgery based on NHS tariffs and hospital costs: does it pay to provide a revision service? Bone Joint J. 2015;97-B(2):197–201. 16. Kendoff D, Gehrke T. Surgical management of periprosthetic joint infection: one-stage exchange. J Knee Surg. 2014;27(4):273–8. 17. Tande AJ. Prosthetic joint infection. In: Patel R, editor: Clinical Microbiology Reviews; 2014. p. 302–345. 18. Corvec S, Portillo ME, Pasticci BM, Borens O, Trampuz A. Epidemiology and new developments in

W. Wignadasan et al. the diagnosis of prosthetic joint infection. Int J Artif Organs. 2012;35(10):923–34. 19. Masters EA, Trombetta RP, de Mesy Bentley KL, Boyce BF, Gill AL, Gill SR, et al. Evolving concepts in bone infection: redefining “biofilm”, “acute vs. chronic osteomyelitis”, “the immune proteome” and “local antibiotic therapy”. Bone Res. 2019;7:20. 20. Davidson DJ, Spratt D, Liddle AD. Implant materials and prosthetic joint infection: the battle with the biofilm. EFORT Open Rev. 2019;4(11):633–9. 21. Aggarwal VK, Bakhshi H, Ecker NU, Parvizi J, Gehrke T, Kendoff D.  Organism profile in periprosthetic joint infection: pathogens differ at two arthroplasty infection referral centers in Europe and in the United States. J Knee Surg. 2014;27(5):399–406. 22. Sendi P, Banderet F, Graber P, Zimmerli W. Clinical comparison between exogenous and haematogenous periprosthetic joint infections caused by Staphylococcus aureus. Clin Microbiol Infect. 2011;17(7):1098–100. 23. Della Valle CJ.  Analysis of frozen sections of intraoperative specimens obtained at the time of reoperation after hip or knee resection arthroplasty for the treatment of infection. In: Sporer SM, Jacobs JJ, Berger, RA, Rosenberg AG, Paprosky WG, editor. J Arthroplasty. 1999:90–3. 24. Kiran M, Donnelly TD, Armstrong C, Kapoor B, Kumar G, Peter V. Diagnostic utility of fluorodeoxyglucose positron emission tomography in prosthetic joint infection based on MSIS criteria. Bone Joint J. 2019;101-B(8):910–4. 25. Osmon DR, Berbari EF, Berendt AR, Lew D, Zimmerli W, Steckelberg JM, et al. Diagnosis and management of prosthetic joint infection: clinical practice guidelines by the Infectious Diseases Society of America. Clin Infect Dis. 2013;56(1):e1–e25. 26. Schäfer P, Fink B, Sandow D, Margull A, Berger I, Frommelt L.  Prolonged bacterial culture to identify late periprosthetic joint infection: a promising strategy. Clin Infect Dis. 2008;47(11):1403–9. 27. Aggarwal VK, Rasouli MR, Parvizi J. Periprosthetic joint infection: Current concept. Indian J Orthop. 2013;47(1):10–7. 28. Lee YS, Koo KH, Kim HJ, Tian S, Kim TY, Maltenfort MG, et  al. Synovial fluid biomarkers for the diagnosis of periprosthetic joint infection: a systematic review and meta-analysis. J Bone Joint Surg Am. 2017;99(24):2077–84. 29. McNally M, Sousa R, Wouthuyzen-Bakker M, Chen AF, Soriano A, Vogely HC, et al. The EBJIS definition of periprosthetic joint infection. Bone Joint J. 2021;103-B(1):18–25. 30. Parvizi J, Tan TL, Goswami K, Higuera C, Della Valle C, Chen AF, et  al. The 2018 definition of periprosthetic hip and knee infection: an evidence-based and validated criteria. J Arthroplasty. 2018;33(5):1309– 14.e2. 31. Schafroth M, Zimmerli W, Brunazzi M, Ochsner PE.  Total hip replacement. Berlin: Springer-Verlag; 2003. p. 65–90.

36  Single-Stage Revision for a Prosthetic Joint Infection After Total Hip Arthroplasty 32. Zimmerli W, Trampuz A, Ochsner PE. Prosthetic-joint infections. N Engl J Med. 2004;351(16):1645–54. 33. Maderazo EG, Judson S, Pasternak H.  Late infections of total joint prostheses. A review and recommendations for prevention. Clin Orthop Relat Res. 1988;229:131–42. 34. Zeller V, Lhotellier L, Marmor S, Leclerc P, Krain A, Graff W, et  al. One-stage exchange arthroplasty for chronic periprosthetic hip infection: results of a large prospective cohort study. J Bone Joint Surg Am. 2014;96(1):e1. 35. Callaghan JJ, Katz RP, Johnston RC.  One-stage revision surgery of the infected hip. A minimum 10-year followup study. Clin Orthop Relat Res. 1999;369:139–43. 36. Leonard HA, Liddle AD, Burke O, Murray DW, Pandit H.  Single- or two-stage revision for infected total hip arthroplasty? A systematic review of the literature. Clin Orthop Relat Res. 2014;472(3): 1036–42. 37. Nguyen M, Sukeik M, Zahar A, Nizam I, Haddad FS.  One-stage exchange arthroplasty for periprosthetic hip and knee joint infections. Open Orthop J. 2016;10:646–53. 38. Oussedik SI, Dodd MB, Haddad FS.  Outcomes of revision total hip replacement for infection after grading according to a standard protocol. J Bone Joint Surg Br. 2010;92(9):1222–6. 39. Yoo JJ, Kwon YS, Koo KH, Yoon KS, Kim YM, Kim HJ.  One-stage cementless revision arthroplasty for infected hip replacements. Int Orthop. 2009;33(5):1195–201. 40. Lange J, Troelsen A, Solgaard S, Otte KS, Jensen NK, Søballe K, et  al. Cementless one-stage revision in chronic periprosthetic hip joint infection. ninety-one percent infection free survival in 56 patients at minimum 2-year follow-up. J Arthroplasty. 2018;33(4):1160–5.e1. 41. Buchholz HW, Elson RA, Engelbrecht E, Lodenkämper H, Röttger J, Siegel A. Management of deep infection of total hip replacement. J Bone Joint Surg Br. 1981;63-B(3):342–53. 42. Jackson WO, Schmalzried TP. Limited role of direct exchange arthroplasty in the treatment of infected total hip replacements. Clin Orthop Relat Res. 2000;381:101–5. 43. Zahar A, Kendoff DO, Klatte TO, Gehrke TA.  Can good infection control be obtained in one-stage exchange of the infected TKA to a rotating hinge design? 10-year results. Clin Orthop Relat Res. 2016;474(1):81–7. 44. Silva M, Tharani R, Schmalzried TP. Results of direct exchange or debridement of the infected total knee arthroplasty. Clin Orthop Relat Res. 2002;404:125–31. 45. Bradbury T, Fehring TK, Taunton M, Hanssen A, Azzam K, Parvizi J, et  al. The fate of acute methicillin-­ resistant Staphylococcus aureus periprosthetic knee infections treated by open debridement and retention of components. J Arthroplasty. 2009;24(6 Suppl):101–4.

481

46. Zahar A, Gehrke TA. One-stage revision for infected total hip arthroplasty. Orthop Clin North Am. 2016;47(1):11–8. 47. Jenny JY, Barbe B, Gaudias J, Boeri C, Argenson JN.  High infection control rate and function after routine one-stage exchange for chronically infected TKA. Clin Orthop Relat Res. 2013;471(1):238–43. 48. Wolf M, Clar H, Friesenbichler J, Schwantzer G, Bernhardt G, Gruber G, et al. Prosthetic joint infection following total hip replacement: results of one-stage versus two-stage exchange. Int Orthop. 2014;38(7):1363–8. 49. George DA, Konan S, Haddad FS.  Single-stage hip and knee exchange for periprosthetic joint infection. J Arthroplasty. 2015;30(12):2264–70. 50. Raut VV, Siney PD, Wroblewski BM. One-stage revision of infected total hip replacements with discharging sinuses. J Bone Joint Surg Br. 1994;76(5):721–4. 51. Krenn V, Morawietz L, Perino G, Kienapfel H, Ascherl R, Hassenpflug GJ, et  al. Revised histopathological consensus classification of joint implant related pathology. Pathol Res Pract. 2014;210(12):779–86. 52. George DA, Haddad FS. One-stage exchange arthroplasty: a surgical technique update. J Arthroplasty. 2017;32(9S):S59–62. 53. Brown NM, Cipriano CA, Moric M, Sporer SM, Della Valle CJ. Dilute betadine lavage before closure for the prevention of acute postoperative deep periprosthetic joint infection. J Arthroplasty. 2012;27(1):27–30. 54. Winkler H, Stoiber A, Kaudela K, Winter F, Menschik F.  One stage uncemented revision of infected total hip replacement using cancellous allograft bone impregnated with antibiotics. J Bone Joint Surg Br. 2008;90(12):1580–4. 55. Schildhauer TA, Robie B, Muhr G, Köller M. Bacterial adherence to tantalum versus commonly used orthopedic metallic implant materials. J Orthop Trauma. 2006;20(7):476–84. 56. Sautet P, Parratte S, Mékidèche T, Abdel MP, Flécher X, Argenson JN, et  al. Antibiotic-loaded tantalum may serve as an antimicrobial delivery agent. Bone Joint J. 2019;101-B(7):848–51. 57. Fink B, Vogt S, Reinsch M, Büchner H.  Sufficient release of antibiotic by a spacer 6 weeks after implantation in two-stage revision of infected hip prostheses. Clin Orthop Relat Res. 2011;469(11):3141–7. 58. Kilgus DJ, Howe DJ, Strang A. Results of periprosthetic hip and knee infections caused by resistant bacteria. Clin Orthop Relat Res. 2002;404:116–24. 59. Kuiper JWP, Rustenburg CME, Willems JH, Verberne SJ, Peters EJG, Saouti R. Results and patient reported outcome measures (PROMs) after one-stage revision for periprosthetic joint infection of the hip: a single-centre retrospective study. J Bone Jt Infect. 2018;3(3):143–9. 60. van den Kieboom J, Tirumala V, Box H, Oganesyan R, Klemt C, Kwon YM. One-stage revision is as effective as two-stage revision for chronic culture-negative periprosthetic joint infection after total hip and knee arthroplasty. Bone Joint J. 2021:1–7.

482 61. Ure KJ, Amstutz HC, Nasser S, Schmalzried TP.  Direct-exchange arthroplasty for the treatment of infection after total hip replacement. An average ten-year follow-up. J Bone Joint Surg Am. 1998;80(7):961–8. 62. Gehrke T, Zahar A, Kendoff D. One-stage exchange: it all began here. Bone Joint J. 2013;95-B(11 Suppl A):77–83. 63. Haddad FS, Ngu A, Negus JJ.  Prosthetic Joint Infections and Cost Analysis? Adv Exp Med Biol. 2017;971:93–100.

W. Wignadasan et al. 64. Moyad TF, Thornhill T, Estok D.  Evaluation and management of the infected total hip and knee. Orthopedics. 2008;31(6):581–8; quiz 9–90 65. Wolff M, Lausmann C, Gehrke T, Zahar A, Ohlmeier M, Citak M. Results at 10–24 years after single-stage revision arthroplasty of infected total hip arthroplasty in patients under 45 years of age. Hip Int. 2019;1120700019888877

Two-Stage Revision for an Infected Total Hip Arthroplasty

37

Shubhranshu S. Mohanty and Sameer Panchal

37.1 Introduction Periprosthetic joint infection is a dreadful complication following total hip arthroplasty. Incidence of PJI varies with the joint involved. Reported incidence is 0.5–1% following primary THA [1]. Around 12–15% revision THA procedures are performed for PJI [1]. Although relatively uncommon, PJI’s are notoriously difficult to treat. Diagnosis of PJI in itself is a challenge and there is no fixed algorithm or universally accepted definition to indicate when to intervene surgically. The introduction of the Musculoskeletal Infection society criteria (MSIS) for PJI has led to improvements in diagnostic confidence and management protocols. Evidence-­based definition for diagnosis of PJI was given by Parvizi et al. based on MSIS criteria in 2018 [2](Table 37.1). The 2018 MSIS criteria have a 97.7% sensitivity and 99.5%

S. S. Mohanty (*) King Edward Memorial Hospital, Mumbai, India S. Panchal Department of Orthopaedics, Grant Medical College and Sir JJ Group of Hospital, Mumbai, India

specificity, compared with 86.9% sensitivity and 79.3% specificity of 2011 MSIS criteria. A collaborative project by the European Bone and Joint Infection Society (EBJIS), MSIS and the European Society of Clinical Microbiology and Infectious diseases (ESCMID) study group for Implant-associated infections (ESGIAI) was designed in 2021 which defines a novel threetier approach for diagnosing PJI based on the most robust evidences (Table  37.2) [3]. The role of interleukin-6 (IL-6) in diagnosing hip PJI is debatable; Qu PF et al. in a retrospective review concluded that serum IL-6 threshold values set at 8.12  pg/mL are associated with high specificity but poor sensitivity to predict persistent infection after reimplantation for two-stage revision arthroplasty [4]. Once the diagnosis is confirmed based on aforementioned criteria, further proceedings are undertaken. PJIs are broadly classified into acute or chronic based on duration of symptoms. Acute PJI is defined as infection occurring within first 6–8 weeks of index surgery. In most instances, it can be managed with antibiotics as per culture and sensitivity, aggressive open debridement with exchange of mobile parts and retention of the implant in stable components especially when the infection is diagnosed within first few weeks. The aim of rapid intervention with thorough open debridement is to prevent the production of any biofilm by the infecting organism, paramount for successful treatment of infection.

© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_37

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484 Table 37.1  Evidence-based PJI criteria based on MSIS criteria by Parvizi et al. (2018) Major criteria (at least one of the following) 1. Two positive cultures of the same organism 2. Sinus tract with evidence of communication to the joint or visualization of prosthesis Serum Synovial

Minor criteria Elevated CRP or D-dimer Elevated ESR Elevated synovial WBC count or leucocyte esterase Positive alpha-defensin Elevated synovial PMN (%) Elevated synovial CRP

Intra-­operative diagnosis

Inconclusive pre-op score or dry tap Pre-operative score Positive histology Positive purulence Single positive culture

Infected

Score 2 1 3 3 2 1 Score – 3 3 2

Decision ≥6 infected 2–5 possibly infected 0–1 not infected

Decision ≥6 infected 4–5 inconclusive ≤3 not infected

Table 37.2  EBJIS definition of PJI (2021) Infection unlikely Clinical and blood workup Clinical features Clear alternative reason for implant dysfunction (e.g. fracture, implant breakage, tumour)

C-reactive protein Synovial fluid cytological analysis Leucocyte count ≤1500 PMN (%) ≤65% Synovial fluid biomarkers Alpha-defensin Microbiology Aspiration fluid Intra-operative (fluid and tissue) Sonication Histology High power field (400× magnification)

Infection likely

Infection confirmed

1. Radiological signs of loosening within the first 5 years after implantation 2. Previous wound healing problems 3. History of recent fever or bacteremia 4. Purulence around the prosthesis >10 mg/dL (1 mg/dL)

Sinus tract with evidence of communication to the joint or visualization of prosthesis

>1500 >65%

>3000 >80% Positive immunoassay or lateral flow assay

All cultures negative

Positive culture Single positive culture

No growth

>1 CFU/mL of any organism

≥2 positive samples with the same micro-organism >50 CFU/mL of any organism

Negative

Presence of >5 neutrophils in a single HPF

Presence of >5 neutrophils in ≥5 HPF Presence of visible micro-organisms

Others Nuclear imaging

Negative three phase isotope bone scan

Positive WBC scintigraphy

37  Two-Stage Revision for an Infected Total Hip Arthroplasty

37.2 Risk Factors for PJI Several demographic factors and comorbid conditions have been implicated as elements of threat for PJI after total hip or knee replacement such as age, sex, race, obesity, addictions, etc. Factors predisposing to PJI as per Annals of Joint (2021) [1].

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37.3 Single-Stage Vs Two-Stage Treatment Dilemma

The three fundamental treatment options to tackle hip PJI include: surgical debridement with antibiotics and implant retention, with or without modular exchange (DAIR); one-stage revision; or two-stage revision. There has been no consensus till date whether single-stage or two-stage approach is superior in managing infection after THA. Proponents of • Patient-specific Systemic conditions single-stage revision have reported comparable outvariables • Male gender • Chronic obstructive comes with one-stage exchange arthroplasty in pulmonary disease (COPD) appropriately selected patients. Raut et al. in a study • Diabetes mellitus • Age ≤ 60 of one-stage cemented revision of infected THA • ASA grade > 3 • Liver failure with actively discharging sinus have shown infec• Obesity • Connective tissue disease tion control rate of 86% at an average follow-up of • Inflammatory arthropathy 7 years [7]. Leonard et al. in a systematic review of literature comparing single versus two-stage reviIn a study by McMaster Arthroplasty sion of infected THA have concluded single-stage Collaborative (MAC) which is a 15-year, revision to be associated with similar re-infection population-­based Cohort Study, it was concluded rates when compared to two-stage revision with that risk of developing PJI following primary superior functional outcome [8]. Two-stage revision THA did not alter despite improvements in other for chronic PJI and complex THA infections is curarthroplasty outcomes. Male sex, type-2 diabetes rently the gold standard with success rate of more mellitus and discharge to convalescent care were than 90% (range 80% to 100%) with many recent associated with increased risk of PJI. The surgi- studies reporting good success rates in eradicating cal approach, income quintile and use of bone-­ infections [9–11]. Based on the available literature, grafting or cement were not significantly standard of care is two-stage revision, although sinassociated with infection [5]. gle-stage revision may have economic and funcMicrobiology associated with PJI as men- tional advantages [12]. First stage usually consists tioned by Tande et  al. in clinical microbiology of adequate tissue ­sampling from multiple areas folreviews is listed in Table 37.3 [6]. lowed by thorough debridement and articulating antibiotic-loaded cement spacer. The clinical Table 37.3  Common micro-organisms responsible PJI’s response of the patient like wound healing and resolution of inflammatory markers along with a nega(% of patients with PJI Causative organism Hip and Knee) tive aspiration determines the decision to proceed Staphylococcus aureus 27% with the insertion of a new prosthesis. Second stage (most common) usually comprises of spacer removal with meticuCoagulase-negative 27% lous debridement, pulse lavage, cement mantle fragstaphylococcus mentation and removal in piecemeal, without Streptococcus species 8% sacrificing bone stock. Enterococcus species 3% Revision components (cemented or cementAerobic gram-negative 9% bacilli less components) are then reimplanted. Allografts Anaerobic bacteria 4% may be used in cases of severe bone loss.

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37.4 Author’s Method of  Two-­Stage Revision 37.4.1 First Stage of Revision The first-stage procedure is meticulous debridement of all dead and infected tissue along with removal of all implants and cement if present. A thorough wash of normal saline (at least 9 liters) is given using low pressure pulse lavage. The appropriate size and length of the articulating spacer is made using antibiotic loaded cement. The cement used is Palacos R  +  G or CMW1 + Gentamycin (40 gm) and loaded with 4–6  g of Vancomycin in all patients and additional antibiotics are included depending on the isolated organism and antibiotic sensitivities which include meropenem, tobramycin, cefuroxime, streptomycin (in active tuberculosis of hips). The indigenous silicone templates used for preparation of cement spacer are made up of 100% medical grade silicone, i.e. polysiloxane, a durable synthetic resin. These templates are reusable, autoclavable and can be used for at least 100 autoclave cycles before disintegration. However, this can be used innumerable times with ethylene oxide (ETO) sterilization. The senior author (SSM) has designed these silicone templates. The templates are soft, malleable and one can adjust the length, offset, diameter, version and it provides rotational stability as well. Hence, there is complete modularity and they can be easily removed during second-stage reimplantation (Fig. 37.1). Size of spacer is decided by operating surgeon considering size of previous hip prosthesis, bone loss, deformity and instability. Five different size templates are available as head size 39, 41, 45, 49 and 51 mm. The scaffold of spacer is supported with metallic endoskeleton during preparation. These include K-nail, Rush nail or Illizarov connecting rod, which is bent to give appropriate neck shaft angle and hence offset. A long length endoskeleton implant is inserted if a severe segmental defect exists or the femur is weakened by osteotomy or osteolysis (Fig. 37.2). Conversely, if femoral bone stock is well main-

Fig. 37.1 Polysiloxane template designed by senior author (SSM) for preparation of articulating antibiotic loaded cement spacer for hip

tained, a short length component is used. The left-over cement is used to prepare beads over a stainless-steel wire to be kept below deep fascia for antibiotic release into soft tissues. These spacers are simply press-fit into the femur to achieve stable fixation. The flattened shoulder of the prosthesis provides rotational stability. If the shoulder of the spacer is not snugly fitting, another 20 gm cement with antibiotics is used to fit it near calcar region with appropriate version. The cement is inserted at a late stage of polymerization to allow for easy removal of the component at the time of the second-stage surgery. The antibiotic beads are kept in sub-fascial layer before closure (Fig. 37.3). After reduction of the joint, the wound is closed in layers with negative suction drains. After surgery, the patients are allowed full weight bearing walking. In most cases, intravenous antibiotics are used for the first 3 weeks after surgery, followed by oral antibiotics for a further 3 weeks. Six weeks of intravenous antibiotics are used for more virulent organisms or if a high ESR/CRP exists even after 3 weeks of intravenous therapy.

37.4.2 Second Stage of  Definitive Surgery At least 6  weeks after the discontinuation of all antibiotics, repeat aspiration of the hip joint is performed for culture and CBC, ESR and CRP tests are repeated. Preoperative planning of involved

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Fig. 37.2 Pre-operative radiograph of a 67 years old female (Diabetes mellitus) with infected excision arthroplasty after multiple hip surgeries

Fig. 37.3  Plain radiograph showing articulating cement spacer with sub-fascial antibiotic loaded cement beads after thorough debridement (stage one of revision)

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hip is done using radiographs of pelvis with both hips AP and lateral views. A wide range of implants are kept ready during revision ­surgery. The second-stage procedure is performed if the aspiration is negative after a period of no antibiotic coverage and ESR and CRP values are in a decreasing trend. At reimplantation, the preexisting surgical approach used for first stage is often utilized. Samples are obtained at various planes and sent for frozen section. On frozen section, polymorph counts of >10/high power field are taken to be evidence of infection as defined by Mirra et al. [13]. If on inspection of frozen section there is no evidence of infection, then the definitive procedure is performed. At final reimplantation (Fig.  37.4), intra-operative specimens are obtained for culture and sensitivity. After the second-stage revision, patients are treated with 2  weeks of intravenous and oral antibiotics until all intra-operative cultures returned as negative for any bacterial growth. The rehabilitation program includes assisted partial weight bearing to full weight bearing walking depending on the stability of the construct and hip range of motion exercises (Figs.  37.5 and 37.6). Sequential radiographs of an infected cemented hemiarthroplasty dealt with by the author’s preferred approach of staged revision visualising the use of articulating spacers in the interim to create a better bio-environment conducive for final implantation (Fig. 37.7).

Fig. 37.5  Plain radiograph after second-stage reimplantation at 5 years follow-up with no signs of loosening or osteolysis

a

b

Fig. 37.4  Plain radiograph (immediate post-operative) after final reimplantation and biodegradable antibiotic impregnated Calcium sulphate cement pellets (Stimulan-­ Biocomposites) in the subcutaneous plane

Fig. 37.6 (a) Clinical photograph of the patient in Fig. 37.2 showing discharging sinus with puckered skin in a patient with chronic PJI of hip. (b) Clinical image of the same patient before second-stage reimplantation with healed scar without any signs of active infection

37  Two-Stage Revision for an Infected Total Hip Arthroplasty

b

a

d

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c

e

Fig. 37.7  A 54  years old male patient with infected cemented bipolar hemiarthroplasty managed by multi-­ stage revision with debridement and cemented spacers. (a) Pre-operative radiograph with radiographic features suggestive of loosening and osteolysis. (b) Stage one—

first spacer with coated Austin Moore prosthesis following debridement (still some cement left behind) (b) Second spacer after extended trochanteric osteotomy (subluxating) (c) Third spacer using the polysiloxan templates (d) Four years follow-up after final reimplantation

37.5 Discussion

superior between single-stage or two-stage revision. BJ Kildow et  al. in a recent review comparing efficacy of single-stage versus two-stage revision for PJI concluded that both the modalities have almost similar infection eradication rate and large randomized controlled trials are required directly comparing the two strategies [14]. Beswick et al. demonstrated no significant

Two-stage revision has stood the test of time and has proven to be the ‘Gold Standard’ for treating PJI and providing better functional outcomes. Although single-stage revision is a promising alternative option for treating PJI, till date there is no consensus as to which is more

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difference in re-­infection rates between singleand two-stage revisions in their systematic review [15]. The advantage of two-stage technique lies in its applicability in a heterogeneous series and allowing uncemented reconstruction. Theoretically, it provides a better environment for eradication of infection. In a meta-analysis by T Bian et  al., several predictors have been analysed to detect persistence of infection in patients with PJI before reimplantation. Synovial polymorphs had the highest sensitivity (70%) followed by serum ESR (57%) and spacer sonication fluid (53%). The predictors with highest specificity were synovial fluid culture (97%) followed by frozen section (93%) and lastly MSIS criteria (92%) [16]. The major limitations with excision arthroplasty between stages have been the loss of mobility of the patient and the difficulty of dissection at the second stage because of adherence of the soft-tissue planes as the joint is no longer mobile. In two-staged arthroplasty using these indigenous spacer templates, particularly with a longer period between stages, we have found the soft-tissue planes to be preserved, improving the ease of the revision surgery at the second stage. Spacers can be broadly classified into non-­ articulating (static) and articulating spacers [17]. The recent International Consensus Meeting on Orthopedic infections has strongly recommended use of articulating spacers in the management of PJI [18]. The existing literature does not strongly recommend one over another; however, following factors should be considered in structuring the final decision: (1) adequacy of bone stock, (2) quality of soft tissues, (3) risk of dislocation and (4) ambulatory status of patient [19]. The hallmark of treating infection is adequate debridement and insertion of antibiotic-coated cement spacer in the first stage. The treatment needs to be cost-effective and outcome needs to be a pain-free mobile joint with good functional improvement. The polysiloxan templates as described by senior author (SSM) are cost-­ effective as they are reusable and also offer complete modularity even in small Asian hips. Salvati et  al. reviewed one- and two-stage procedures published in the literature and concluded that the

success rate of one-stage exchange with antibiotic-­loaded cement was 73%, and that with two-stage exchange was 87% [20]. Clive Duncan et  al. in 1997 and 2011 (PROSTALAC study) [21, 22] showed infection eradication rate of 98% and overall success rate of 90% with two-stage arthroplasty using cement spacers with average HHS improvement as 34, 56 and 76 for preoperative, after first stage and second stage, respectively. Chalmers BP et  al. in a retrospective review including 131 patients with PJI undergoing two-stage revision THA with specific articulating antibiotic spacer design at mean follow-up of 5 years inferred predictable infection eradication and improvement in functional outcome with 92% and 88% survivorship free of any infection after reimplantation at 2 and 5 years, respectively [23]. Comparable results were also evident from a study by Takahira N et al. [24] in which total of nine hip PJI’s were managed by two-stage revision with mean follow-up of 35.7  months and improvement in mean JOA (Japanese Orthopaedic Association) hip score from 30.1 to 73.2. First stage comprised of implantation of antibiotic impregnated cement spacer with mean interval of 10.1 weeks between two stages. Cementless revision was performed during second-stage revision for all the patients, one out of nine hips experienced recurrence of infection. Kang JS et al. in a long-term retrospective review of 85 patients with PJI managed by two-stage revision with mean follow-up of 7.4 years concluded that the clinical outcome, prognosis of culture-negative PJI (CN-PJI), was better than culture positive PJI and even CN-PJI can be effectively managed by two-­stage exchange arthroplasty with no treatment failure or complications [25].

37.6 Summary Periprosthetic joint infection is a well-known but gruelling complication following primary THA imposing physical, psychological and financial burden. Single-stage revision of infected total hip arthroplasty is technically demanding, though some studies have demonstrated high success rate with specific patient selection criteria. Two-stage

37  Two-Stage Revision for an Infected Total Hip Arthroplasty

revision of an infected THA is an effective, technically sound approach to tackle PJI with successful eradication of infection, restoration of function with satisfactory clinical and radiological outcome at the expense of minimum complications.

References 1. Sandiford NA, Franceschini M, Kendoff D. The burden of prosthetic joint infection (PJI) Ann. Jt. 2020;6:25. https://doi.org/10.21037/aoj-2020-pji-11. 2. Parvizi J, Tan TL, Goswami K, Higuera C, Della Valle C, Chen AF, Shohat N.  The 2018 ­definition of Periprosthetic hip and knee infection: an evidence-­based and validated criteria. J Arthroplast. 2018;33(5):1309–1314.e2. https://doi.org/10.1016/j. arth.2018.02.078. 3. McNally M, Sousa R, Wouthuyzen-Bakker M, Chen AF, Soriano A, Vogely HC, Trebše R. The EBJIS definition of periprosthetic joint infection. Bone Joint J. 2021;103-B(1):18–25. https://doi.org/10.1302/0301-­ 620X.103B1.BJJ-­2020-­1381.R1. 4. Qu PF, Xu C, Fu J, Li R, Chai W, Chen JY.  Does serum interleukin-6 guide the diagnosis of persistent infection in two-stage hip revision for periprosthetic joint infection? J Orthop Surg Res. 2019;14(1):354. Published 2019 Nov 11. https://doi.org/10.1186/ s13018-­019-­1448-­7. 5. McMaster Arthroplasty Collaborative (MAC). Risk factors for Periprosthetic joint infection following primary Total hip arthroplasty: a 15-year, population-based cohort study. J Bone Joint Surg Am. 2020;102(6):503–9. https://doi.org/10.2106/ JBJS.19.00537. PMID: 31876641 6. Tande AJ, Patel R.  Prosthetic joint infection. Clin Microbiol Rev. 2014;27(2):302–45. https://doi. org/10.1128/CMR.00111-­13. PMID: 24696437; PMCID: PMC3993098 7. Raut VV, Siney PD, Wroblewski BM.  One-stage revision of total hip arthroplasty for deep infection. Long-term followup. Clin Orthop Relat Res. 1995;321:202–7. PMID: 7497670 8. Leonard HA, Liddle AD, Burke O, Murray DW, Pandit H. Single- or two-stage revision for infected total hip arthroplasty? A systematic review of the literature. Clin Orthop Relat Res. 2014;472(3):1036–42. https:// doi.org/10.1007/s11999-­013-­3294-­y. Epub 2013 Sep 21. PMID: 24057192; PMCID: PMC3916596 9. Charette RS, Melnic CM. Two-stage revision arthroplasty for the treatment of prosthetic joint infection. Curr Rev Musculoskelet Med. 2018;11(3):332–40. https://doi.org/10.1007/s12178-­018-­9495-­y. 10. Oussedik SI, Dodd MB, Haddad FS.  Outcomes of revision total hip replacement for infection after grading according to a standard protocol. J Bone Joint Surg Br. 2010;92(9):1222–6. https://doi.org/10.1302/0301-­ 620X.92B9.23663. PMID: 20798438

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11. D’Angelo F, Negri L, Binda T, Zatti G, Cherubino P. The use of a preformed spacer in two-stage revision of infected hip arthroplasties. Musculoskelet Surg. 2011;95(2):115–20. https://doi.org/10.1007/ s12306-­011-­0128-­5. Epub 2011 Apr 9. PMID: 21479729 12. Haddad FS, Muirhead-Allwood SK, Manktelow AR, Bacarese-Hamilton I. Two-stage uncemented revision hip arthroplasty for infection. J Bone Joint Surg Br. 2000;82(5):689–94. https://doi.org/10.1302/0301-­ 620x.82b5.9668. PMID: 10963167 13. Mirra JM, Amstutz HC, Matos M et.al. The pathology of the joint tissues and its clinical relevance in prosthesis failure. Clin Orthop 1976; 117:221. 14. Kildow BJ, Della-Valle CJ, Springer BD.  Single vs 2-stage revision for the treatment of Periprosthetic joint infection. J Arthroplast. 2020;35(3S):S24–30. https://doi.org/10.1016/j.arth.2019.10.051. PMID: 3204682 15. Beswick AD, Elvers KT, Smith AJ, Gooberman-Hill R, Lovering A, Blom AW. What is the evidence base to guide surgical treatment of infected hip prostheses? Systematic review of longitudinal studies in unselected patients. BMC Med. 2012;10:18. https:// doi.org/10.1186/1741-­7015-­10-­18. PMID: 22340795; PMCID: PMC3364856 16. Bian T, Shao H, Zhou Y, Huang Y, Song Y. Tests for predicting reimplantation success of two-stage revision for periprosthetic joint infection: a systematic review and meta-analysis. Orthop Traumatol Surg Res. 2018;104(7):1115–23. https://doi.org/10.1016/j. otsr.2018.03.017. Epub 2018 Jul 17. PMID: 30030145 17. Sporer SM.  Spacer design options and consideration for Periprosthetic joint infection. J Arthroplast. 2020;35(3S):S31–4. https://doi.org/10.1016/j. arth.2019.11.007. PMID: 32046828 18. Belden K, Cao L, Chen J, Deng T, Fu J, Guan H. Hip and knee section, fungal peri-prosthetic joint infection, diagnosis and treatment: proceedings of international consensus on orthopedic infections. J Arthroplast. 2019;34:S387–91. 19. Wyles CC, Abdel MP. Point/counterpoint: nonarticulating vs articulating spacers for resection arthroplasty of the knee or hip. J Arthroplast. 2020;35(3S):S40–4. https://doi.org/10.1016/j.arth.2019.10.055. PMID: 32046830 20. Salvati EA, Chekofsky KM, Brause BD, Wilson PD.  Reimplantation in infection: a 12-year experience. Clin Orthop. 1982;170:62. 21. Younger TSE, Duncan CP, Masri BA, McGraw RW.  The outcome of two-stage arthroplasty using a custom-made interval spacer to treat the infected hip. J Arthroplasty. 1997;12(6):615. 22. Masri BA, Panagiotopoulos KP, Greidanus NV, Garbuz DS, Duncan CP.  Cementless two-stage exchange arthroplasty for infection after Total hip arthroplasty. J Arthroplast. 2007;22(1):72. 23. Chalmers BP, Mabry TM, Abdel MP, Berry DJ, Hanssen AD, Perry KI.  Two-stage revision Total hip arthroplasty with a specific articulating anti-

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biotic spacer design: reliable Periprosthetic joint spacer. J Orthop Sci. 2003;8(1):26–31. https://doi. infection eradication and functional improvement. org/10.1007/s007760300004. PMID: 12560882 J Arthroplast. 2018;33(12):3746–53. https://doi. 25. Kang JS, Shin EH, Roh TH, Na Y, Moon KH, org/10.1016/j.arth.2018.08.016. Epub 2018 Aug 27. Park JH.  Long-term clinical outcome of twoPMID: 30236495 stage revision surgery for infected hip arthro24. Takahira N, Itoman M, Higashi K, Uchiyama K, plasty using cement spacer: culture negative Miyabe M, Naruse K.  Treatment outcome of two-­ versus culture positive. J Orthop Surg (Hong stage revision total hip arthroplasty for infected hip Kong). 2018;26(1):2309499017754095. https://doi. arthroplasty using antibiotic-impregnated cement org/10.1177/2309499017754095. PMID: 29366392

Part V Navigation and Robotics in Total Hip Arthroplasty

Computer-Assisted Navigation in Total Hip Arthroplasty

38

Kamal Deep and Frederic Picard

38.1 Introduction Computer-assisted navigation started in late 1990s and got more popular in early twenty-first century. It is one of the most path breaking developments in joint replacement surgery. The joint replacement arthroplasty itself is less than a century old, but it has progressed at a fast pace, learning from failures to advance the science of fixation techniques, bearing surfaces, materials, and prosthetic surface. The techniques to do surgery also evolved with different approaches to do the surgery. Understanding of the biomechanics happened along the way, but its reproduction to a precise level remained a challenge. The use of technology and computer assistance in the surgery, navigation, or robotics helped with this and we are now able to reproduce our pre-operative plans more accurately than using conventional techniques. Although both use computers and navigation as part of intraoperative feedback, there is a difference in robotic surgery and computer navigation as the former has an additional executing arm of the robot guiding and the latter is performed mainly by surgeons. Presently, available robotic systems are mainly based on computer navigation technology, with assistance in the bone preparation by the robot, thus combining K. Deep (*) · F. Picard Golden Jubilee National Hospital, Glasgow, UK e-mail: [email protected]

the two technologies and using the advantages of both. In this chapter, we will describe the computer-­assisted navigation part. Computer assisted orthopedic surgery (CAOS) in total hip replacement (THR) has not been as popular as in total knee arthroplasty. The main reason for this is that THR is more forgiving. Implant malpositioning does not cause immediately visible issues as seen in the TKR.  Also, the satisfaction rates in THR are much better than TKR. With time, surgeons are realising the importance of biomechanics and potential advantages in the THR.  The problems associated with implant malpositioning include dislocation, impingement, leg length discrepancy, pain, and early failure [1–3]. Impingement is related to failure in use of ceramics [3, 4]. With metal on metal bearings, the metal ion release is increased in mal-placed implants [5]. There is still no agreement on the standardised orientation of the acetabular cup, although safe zones like Lewinnek have been described [6]. The functional plane is different from anatomical plane for every person. There may be contractures of different degrees in the arthritic hips. This is also applicable for routine conventional techniques. The present computer navigation systems use anterior pelvic plane as the reference plane for determining the orientation of the pelvis. This plane helps register consistent fixed bony points, but it may not represent a true reference in every individual as functional position may be different. Various alternative reference planes have

© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_38

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been tried, but did not prove to be superior to anterior pelvic plane. These include posterior superior iliac spines and transverse acetabular ligament. The anterior pelvic plane registration may be difficult to register in imageless navigation if the surgeon uses lateral position and patient is obese.

38.2 Potential Advantages Computer navigation provides information of individual patient-specific anatomy, based on which the surgeon can make a plan for bone preparation to produce optimum result. For the acetabular side, the computer can show the surgeon, in real time, the orientation, while placing the cup, in all 6° of freedom. It shows inclination, anteversion, flexion, and any cup centre shifting anteroposterior, mediolateral, and superoinferior that the surgeon is creating. Surgeon can correct these at the time of surgery itself. For the femoral stem, depending on the system being used, it can show the varus/valgus, flexion/extension, anteversion, offset, and leg length changes. Most of the navigation systems available should show the above parameters. It has been shown that computer navigation increases the accuracy of anatomical placement as compared to conventional techniques even in experienced hands [1, 7, 8]. It has also been shown to help correct leg length discrepancy and offset better than conventional technique [3, 9–12]. So, the problems of conventional surgery that are related to implant malplacement like dislocation, impingement, and leg length discrepancy should be addressed by using computer navigation. The pelvis itself is not rigidly fixed on the table per operatively and can move during the procedure, without knowledge or control of the surgeon as it is under the drapes. So the chances of misplacement of the cup are increased. With the use of navigation, the movement of the pelvis is tracked by the computer and the chances of misplacement are much less. It is anticipated that CAOS can prevent early failures and lead to better function and increased

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longevity of the implants. It has been proven to achieve the peak flexion equivalent to the other normal hip in gait analysis studies [13]. It has also been shown to reduce the noise in ceramic-­ on-­ceramic bearing hips [14]. It has been shown to be helpful in training young resident surgeons and helps produce accurate results in trainees’ hands, which compare well with experienced surgeons [15, 16]. It is also helpful in minimally invasive approaches, where the field of view is limited [17]. Computer guides the surgeon through different stages of the procedure and shows in real time on the screen what he/she is doing. Unfortunately, the CAOS techniques have not been used too widely; it is difficult to state if these statements will hold true in general use, but it does make sense, based on the literature.

38.3 Potential Disadvantages There is a potential for tracker/rigid body attachment site morbidity, as one has to make a hole in the bone to which tracker attachment device is attached. There is a potential for trackers to move, as the pelvis can be porotic especially in old patients, in whom generally the THR is undertaken. Bone anatomy registration can be inaccurate, especially in obese patients when the lateral position is used for operating. The procedure may take few minutes longer than conventional technique. In the beginning, it can add up to 20–30 min, which comes down to 5–10 min after the learning curve is over. Time is also helped once the operating theatre staff also gets used to the system.

38.4 Operative Technique Here we describe the technique used in computer navigation for imageless registration method, where no pre-operative imaging specific to navigation is required. This is the most commonly used technique for hip navigation. We are describing here only the steps, which are important from navigation point of view. One must

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know how to do a conventional hip replacement arthroplasty and its principles. Computerassisted surgery involves various stages as does the conventional surgery. The method described here is one used by us, but there are many computer navigation systems on the market and there can be variations with different navigation systems.

38.4.1 System Setup The patient and part preparation is done as in conventional surgery. There may be a need to keep the iliac crest exposed and accessible during surgery for some systems for tracker pin attachment. Patient positioning can be supine or lateral. The limb is prepared from lower chest to foot. It is important that one can access the knee and ankle (under the drape is acceptable) for femoral plane registration. Iliac crest is for attaching the trackers to the bone. Access to the anterior superior iliac spine and pubic symphysis is needed to register for the pelvic plane. Some systems use attachment of pelvic trackers to the iliac tuberosity, while some use supra acetabular area to attach the pelvic tracker (Fig.  38.1). In the obese individuals, if one is using the lateral position with posterior approach, it may be easier to register the pelvis by surgeon coming to the front of the patient. Some surgeons may leave the patient first in sloppy lateral position, till registration of the pelvis is done, and then tighten the posterior supports. ECG dots may also be used to guide under the drapes for palpation of relevant points. Surgeon and patient details and side are fed into the computer system. The trackers and instruments are calibrated and registered as needed. The trackers are attached to pelvis and femur with fixation techniques depending on the computer system in use (Figs. 38.1 and 38.2). The camera is adjusted to make sure both the trackers are visible and are at a proper distance. Preferably, camera should be out of surgical field and not disrupt the laminar flow. The computer screen indicates if the camera cannot see any of the trackers.

Fig. 38.1  The tracker attachment devices are attached to the pelvis and femur. (A diamond cut end pelvic pin in supra acetabular area and a C clamp tightened around the femur)

Fig. 38.2  Passive tracker reflective balls are attached to the pelvis and femur and anatomy is registered

38.4.2 Registration of Pelvis and Acetabulum This can be image-based (on pre-operative CT scan or intraoperative fluoroscopy) or imageless where there is no radiological imaging required. We use the imageless method of registration. The pelvic plane registration is done by frontal plane made by the two anterior superior iliac spines and pubic tubercles or pubic symphysis. Some computer systems also register a functional plane, made by mid-axillary point and greater trochanter in neutral position of the leg. It can be difficult to reproduce, as both these points are not single discrete bony points and are open to errors. The relative position of the pelvic and femoral planes is registered by the computer. The hip joint is

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approached and exposed as in the conventional surgery, neck osteotomy is made, and head of the femur taken out. The acetabular registration is then done by registering true medial wall, acetabular surface, and periphery of the margin. This gives an approximate diameter of the acetabulum and the native anatomy and acetabular plane. A reamer or acetabular trial of the same diameter can be used to insert in the acetabulum and the centre of the reamer is thus registered, by ­computer as the centre of hip. This centre acts as a reference for further calculations in change of the cup centre. This is also used to record the original orientation of the native acetabulum.

K. Deep and F. Picard

Fig. 38.3  Acetabular cup reaming is done using a tracker attached to the reamer handle

38.4.3 Femoral Registration This varies in different computer systems. In the one we use, it is recorded by the anterior mid-­ patellar point, with leg positioned in 90-degree flexion of the knee to capture the centre of the knee. The anterior mid-ankle point is recorded with tracked pointer to create the femoral reference plane. In another system, the trochanteric fossa is registered first, followed by popliteal fossa, which can be recorded either by a single point in middle of the fossa or by registering the medial and lateral femoral epicondyles. The knee is then flexed to 90° to avoid the effect of leg rotation and midpoint of the Achilles tendon is registered. There is also an option to register the centre of ankle. These points help computer system to create a virtual femoral plane and act as a reference for the femoral part.

38.4.4 Acetabular Cup After full exposure of the acetabulum, acetabular reamers are used to prepare the cup bed. Tracker is attached to the reamer handle, which communicates with the computer to give orientation and position of the reamer, in all 6° of freedom. On the screen, surgeon can see the inclination, version, flexion, and superoinferior, anteroposterior, and mediolateral shift of the cup centre (Figs. 38.3 and 38.4). Similar information is shown, when the cup is inserted, as a computer tracker is

Fig. 38.4  The acetabular reaming screen showing the reamer size, antero posterior, medio lateral, cranio caudal shift in the cup centre position. It also shows the inclination, anteversion, and distance to the true floor (The middle bar)

attached to the cup insertion handle. For the uncemented cups, it is important to be careful when preparing the cup with reamers to be in correct orientation as guided by the computer. For the cemented cups, one can still change the orientation of the cup, within the cement mantle to some extent. Surgeon can see the computer screen showing the exact orientation, so one can change the position before finally seating the implant (Figs. 38.5, 38.6, and 38.7). The ideal cup position is not known for every individual and differs in different patients depending on their anatomy, spino pelvic relationship, fixed spinal deformities, pre-existing leg length inequalities, etc. This is where navigation and technology are even more helpful. As the

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the Lewinnek safe zone, especially in relation to inclination [18]. Some surgeons use transverse acetabular ligament (TAL) as the guide for their cup placement. The orientation of original transverse acetabular ligament in relation to pelvic plane has not been shown to be very accurate, especially in relation to the inclination [19]. It has been authors’ experience that TAL is most useful mainly for anteversion, if one is able to achieve 40° of inclination by any other technical means, such as navigation or robotics. Fig 38.5  After reaming cup is fixed in desired orientation with help of tracker attached to cup insertion handle

38.4.5 Femoral Stem

Fig. 38.6  Final Cup Positioning screen showing the inclination and anteversion

After good exposure of the upper end, the femoral preparation is done. The first box chisel cut and first femoral broach determine the anteversion of the stem one will have. This first broach orientation is important. The rest usually follows the track created by the first one. The tracker is attached to the femoral broach handle, taking care of the correct orientation, which is shown by the computer. It can show various measurements the surgeon is interested in, including version, offset, and lengthening and virtual range of motion the hip will have if that much anteversion is used (Fig. 38.8). Similar readings can be seen when inserting stem component. In the uncemented stems, it is important to be careful at the time of preparation of bed. In the cemented stems, one can alter the position to some extent in the cement mantle. The navigation technique helps with this as you have the numbers in front of your eyes real time.

38.4.6 Final Steps

Fig. 38.7  Clinical picture of the Acetabular cup with the ceramic liner after insertion

surgeon can see where exactly the orientation is, he/she can plan it accordingly. Some surgeons tend to place the cup in native arthritic acetabular orientation which has shown to be suboptimal for

A virtual reduction is visible on the screen and effect of various lengths of femoral neck can be seen, even without the actual hip trial reduction (Fig. 38.8). The appropriate neck length is selected, and trial reduction is then done. A change of leg length and offset can be seen on the computer screen, which is changeable to some extent, even at this stage, by varying the neck length. The final implant position, offset change, leg length change, and range of movements are

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38.6 Summary and Future of CAOS

Fig. 38.8  The femoral rasping showing internal and external rotations that will be achieved by the shown anteversion of the rasp position. The lower part of the screen shows virtual trial including the offset, size of the head, neck, and stem and the change it will make to the leg length and offset by using different neck lengths: short (S), medium (M), long (L), and extra-long (XL)

recorded in the computer and procedure is finished. Trackers are taken off and wound closure is done in layers as in conventional technique.

38.5 Discussion Further development in the CAOS technology (Navigation and robotics) specific to THR needs to take place before these are accepted as a conventional technique by all. The registration process needs to be simplified and the reference plane needs to be standardised. The present methods need to be modified; the instrumentation needs to be directed to CAOS technology. A whole new range of implants need to be made, which can properly reproduce the optimal biomechanics. The research with navigation has exposed the weakness of currently existing inventories of implants. The extramedullary vs intramedullary dimensions differ for different patients. We can no longer justify the same implant for everyone in the wake of the technology available, which shows individual dimensions to be different than others and which many times does not reproduce the original anatomy of the patients.

It is the opinion of the authors that the technology will be much simpler and user-friendly in future. Navigation is already merging with robotics to take advantages of both systems. The computer technologies will be used for pre-operative assessment and even post-operative evaluation of kinematics, implants, and track their progress with time, recognising early failures before it actually happens. Preventive steps may be applicable then. It is also going to be helpful to train the surgeons with virtual/simulated workstations. We are already seeing the inclusion of virtual reality during the surgery itself. Simulated workstations can also act as an evaluating tool for examination purposes for trainees. The potential of CAOS technology for research and understanding of biomechanics of humans is huge and will no doubt assist us in giving better outcomes to our patients. The future of CAOS technologies remains positive with the prospect of new technologies with improvements in image-guided surgery, robotics, 3D printing, virtual reality, individualised implants, and artificial intelligence [20].

References 1. Wixson RL.  Computer-assisted total hip navigation. Instr Course Lect. 2008;57:707–20. 2. Ecker TM, Murphy SB. Application of surgical navigation to total hip arthroplasty. Proc Inst Mech Eng. 2007;221(7):699–712. 3. Sugano N, Nishii T, Miki H, Yoshikawa H, Sato Y, Tamura S.  Mid-term results of cementless total hip replacement using a ceramic-on-ceramic bearing with and without computer navigation. J Bone Joint Surg Br. 2007;89(4):455–60. 4. Murali R, Bonar SF, Kirsh G, Walter WK, Walter WL. Osteolysis in third-generation alumina ceramic-­ on-­ceramic hip bearings with severe impingement and titanium metallosis. J Arthroplast. 2008;23(8):1240. e13–9. Epub 2008 Apr 3 5. Onda K, Nagoya S, Kaya M, Yamashita T. Cup-neck impingement due to the malposition of the implant as a possible mechanism for metallosis in metal-on-metal total hip arthroplasty. Orthopedics. 2008;31(4):396. 6. Lewinnek GE, Lewis JL, Tarr R, Compere CL, Zimmerman JR.  Dislocations after total

38  Computer-Assisted Navigation in Total Hip Arthroplasty h­ ip-­replacement arthroplasties. J Bone Joint Surg Am. 1978;60(2):217–20. 7. Deep K, Picard F.  Computer assisted navigation in Total hip arthroplasty. Orthopaedics Trauma. 2014;28(5):309–14. https://doi.org/10.1016/j. mporth.2014.08.004. 8. Deep K, Shankar S, Mahendra A. Computer assisted navigation in Total knee and hip arthroplasty. SICOT J. 2017;3:50. https://doi.org/10.1051/SICOTJ/2017034. 9. Confalonieri N, Manzotti A, Montironi F, Pullen C. Leg length discrepancy, dislocation rate, and offset in total hip replacement using a short modular stem: navigation vs conventional freehand. Orthopedics. 2008;31(10 Suppl 1):35. 10. Ellapparadja P, Mahajan V, Atiya S, Sankar B, Deep K.  Leg length discrepancy in computer navigated total hip arthroplasty: how accurate are we? Hip Int. 2016;26(5):438–43. https://doi.org/10.5301/ hipint.5000368. 11. Ellapparadja P, Mahajan V, Deakin AH, Deep K.  Reproduction of hip offset and leg length in navigated total hip arthroplasty: how accurate are we? J Arthroplast. 2015;30(6):1002–7. https://doi. org/10.1016/j.arth.2015.01.027. Epub 2015 Jan 23.PMID: 25677938 12. Dastane M, Dorr LD, Tarwala R, Wan Z. Hip offset in total hip arthroplasty: quantitative measurement with navigation. Clin Orthop Relat Res. 2011;469(2):429– 36. https://doi.org/10.1007/s11999-­010-­1554-­7. 13. Leonard HJ, Ewen AM, Deep K. Peak active hip flexion following navigated total hip arthroplasty. EPiC Ser Health Sci. 2019;3:223–7. https://easychair.org/

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publications/paper/bX2V. https://doi.org/10.29007/ z9fd. 14. Deep K, Shah S, Siramanakul C, Mahajan V, Picard F, Allen DJ.  Computer navigation helps reduce the incidence of noise after ceramic-on-ceramic total hip arthroplasty. J Arthroplast. 2017;32(9):2783–7. https://doi.org/10.1016/j.arth.2017.04.019. 15. Gofton W, Dubrowski A, Tabloie F.  Backstein D the effect of computer navigation on trainee learning of surgical skills. J Bone Joint Surg Am. 2007;89(12):2819–27. 16. Picard F, Moholkar K, Gregori A, Deep K, Kinninmonth A.  Role of computer assisted surgery in training and outcomes. Orthopaedics Trauma. 2014;28(5):322–6. https://doi.org/10.1016/j. mporth.2014.08.006. 17. Judet H.  Five years of experience in hip navigation using a mini-invasive anterior approach. Orthopedics. 2007;30(10 Suppl):S141–3. 18. Goudie ST, Deakin AH, Deep K. Natural acetabular orientation in arthritic hips. Bone Joint Res. 2015;4:6– 10. https://doi.org/10.1302/2046-­3758.41.2000286. Bone and Joint 360 April 2015 4:32–34 19. Deep K, Prabhakra A, Mohan D, Mahajan V, Sameer M.  Orientation of transverse acetabular ligament in relation to anterior pelvic plane. Arthroplasty Today. 2020;7:1–6. https://doi.org/10.1016/j. artd.2020.11.018. 20. Picard F, Deakin AH, Riches P, Deep K, Baines J. Computer assisted orthopaedic surgery: past, present and future. Med Eng Phys. 2019;72:55–65. https:// doi.org/10.1016/j.medengphy.2019.08.005.

Overview of Robotics in Total Hip Arthroplasty

39

James A. Dalrymple, Mazin S. Ibrahim, Babar Kayani, Ajay K. Asokan, and Fares S. Haddad

39.1 Introduction

accuracy of implant positioning compared to conventional THA. This is achieved through preTotal Hip Arthroplasty (THA) has become the operative three-dimensional planning and temdefinitive procedure for treating end-stage osteo- plating and a robotic machine in theatre to arthritis (OA) of the hip, with over 95,000 per- minimise surgeon error in executing this plan. formed annually within the United Kingdom Robotic technology has gained an ever-­ (UK) alone [1]. Since the revolutionary low-­ expanding role within various surgical fields, and friction implants introduced by Charnley in 1971, its use within arthroplasty has grown in populara number of important technologies have been ity over the last decade [16, 17]. A number of incorporated into implant design and technique robotic systems exist, sharing the principle aims including cementless implant surfaces to pro- of improving component positioning and subsemote osseointegration, modular femoral compo- quent restoration of hip biomechanics. Failure to nents to restore native hip kinematics, and address these parameters has been shown to lead improved bearing surfaces with highly cross-­ to joint instability [18], increased wear [19], and linked polyethylene and modern ceramics [2–15]. poor functional outcomes [20–23]. R-THA sysThese advances have allowed modern implants to tems may be classified as passive, active (autonosurvive well beyond 90% at 10-years [1]. mous), or semi-active (haptic) dependent on the However, 5–14% of patients undergoing THA level of surgeon input; with the latter proving are not satisfied with the outcome of their sur- more popular in recent systems [24]. The first gery, with the aetiology of this dissatisfaction robotic system to perform R-THA was the remaining known in most patients [1]. There are ROBODOC (Curexo Technology Corporation, also problems surrounding wear rates and joint Fremont, California, USA), which was a fully instability, thus to address these matters and autonomous system used to mill the proximal enhance clinical outcomes, robotic-assisted THA femur to accommodate a press-fit femoral com(R-THA) has been developed. Robotic Total Hip ponent. Since then a number of other systems Arthroplasty (R-THA) aims to improve patient have been developed including CASPAR outcomes by more precisely restoring the (Universal Robotic Systems Ortho, Germany), patient’s native biomechanics and improving the ACROBOT (The Acrobot Co. Ltd., London, UK), TSolution ONE, and finally The Mako Robotic Arm Interactive Orthopaedic System J. A. Dalrymple · M. S. Ibrahim (*) · B. Kayani · (Stryker Corporation, Kalamazoo, MI, USA) A. K. Asokan · F. S. Haddad [25]. Of these, the Mako remains the most widely University College London Hospitals, London, UK used and well researched and will be the focus of e-mail: [email protected] © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_39

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this chapter. It should be noted that many systems claim to be ‘robotic,’ but vary considerably in their approach, and so each should be evaluated upon its individual outcomes. The Mako system utilises a preoperative three-dimensional patient-­ specific planning model and an intraoperative robotic arm to help execute the surgical plan with a high level of accuracy. The Mako system helps to restore planned leg length, combined offset, and centre of rotation, while creating patient-­ specific safe zones for implant positioning using assessments of the spinopelvic kinematics, range of motion, and component stability. Conceptually, this may help to produce a patient-specific THA that improves patient satisfaction, functional outcomes, and implant survivorship. This chapter provides an overview of the operative stages for R-THA using the Mako robotic THA System (Stryker, Kalamazoo, MI, USA), evaluates the role of this technology in component positioning and hip biomechanics, and explores how these outcomes influence patient

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satisfaction and functional outcomes compared with manual THA (M-THA). The Mako is a semi-active robotic system for both hip and knee arthroplasty, comprising a robotic arm with bone resecting instruments, peripheral camera for optical calibration, and separate monitor (Fig. 39.1). It requires a preoperative computed tomography (CT) scan of both hips and the proximal femurs to create a 3D model to allow templating of both femoral and acetabular components. Intraoperatively, bone resections are made within a virtual stereotactic boundary created by haptic feedback. Resections and implant positioning can be adjusted intraoperatively using real-time information to provide optimal component positioning and alignment, which ensures restoration of hip biomechanics, bone coverage, and desired leg-length [24]. Finally, definitive acetabular component is inserted with the help of the Mako robot, while the femoral component is placed manually, with combined version and leglength displayed digitally.

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Fig. 39.1 (a) MAKO Robotic-assisted surgical system. (b) Pelvic and Femoral arrays shown inserted through separate incisions with the monitor in the background

39  Overview of Robotics in Total Hip Arthroplasty

39.2 Stages of RoboticAssisted THA There are four distinct stages to Robotic THA, which will be explored in turn.

39.2.1 Preoperative Planning Preoperative planning is crucial to the success of any THA, but there is variability between different robotic systems. The Mako requires a preoperative CT scan using a Mako-specific protocol of the pelvis and both proximal femurs. This scan is then transferred to a remote design team who creates a 3D computer-aided design (CAD) model of the pelvis and femur. This model allows for pelvic orientation in the axial, sagittal, and coronal planes, which enables accurate assessment and planning for restoration of hip biomechanics [26]. The Mako Product Specialist (MPS) will then create an initial preoperative plan and select the osseous landmarks for intraoperative registration. This is sent to the operating surgeon for review and final adjustments prior to surgery. The surgeon is able to adjust the initial template to ensure optimal templating of component size and alignment, thus allowing the desired restoration of hip biomechanics, bone coverage, component positioning, and leg-length correction [24]. The computer software is used to identify the appropriate CT landmarks to calculate hip length and combined offset in the coronal plane. The affected hip is compared to the contralateral side. To improve accuracy, any change in hip length is calculated with both anterior superior iliac spines (ASIS) and the mechanical axis of the femur aligned parallel to the coronal plane. Combined offset is calculated by measuring the distance from the midline axis of the pelvis to the centre of the mechanical axis of the femur. During the next step, the correct size and position of the acetabular cup are planned. The aim is to select the correct version and inclination while maintaining adequate bony coverage in order to achieve good fixation. Once this is completed, the femoral stem size, position, and version are

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planned; this can be adjusted to allow the surgeon to select the correct combined offset and leg length. The selected implants can be viewed in position in the reduced mode of the computer software. This allows the surgeon to visualise and assess how the final implanted components will fit and align into the hip joint. An example of this process is outlined in the figures below. With the introduction of new software (version 4.0), other parameters can be taken into consideration including the spinopelvic relationship and the virtual range of movement. The former will help to accommodate major changes within the spine that can affect the pelvic alignment. This can be checked preoperatively by manually calculating and inserting values for the pelvic tilt and sacral slope from standing and sitting lateral radiographs of the hip. Virtual range of movement allows preoperative assessment for any impingement. Both of these parameters are shown in Fig.  39.2. Importantly, this new software enables the surgeon to use each patient’s unique osseous anatomy and spinopelvic kinematics to create patient-specific safe zones for implant positioning and alignment and achieve the planned hip biomechanics with greater accuracy than M-THA.

39.2.2 Intraoperative Calibration The Mako system is validated for use on the majority of common surgical approaches to the hip, including the posterior, anterolateral, and direct anterior approaches. The key to patient positioning is stability in order to minimise movements that will affect the acetabular reaming and cup insertion. The Mako system relies upon insertion and calibration of optical arrays which in combination with optical motion capture technology allow ‘registration’ of the bone to calibrate the on-table anatomy to the preoperative CT scan and CAD model. Bone registration has three stages: patient landmarks to orientate anatomy; fine registration; and verification. These are performed separately for both the acetabulum and femur.

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Fig. 39.2 (a) The preoperative planning of the pelvic tilt angle. (b) The preoperative planning of the pelvic slope using a standing lateral x-ray of the pelvis. (c) The preop-

erative assessment of virtual range of motion assessing for impingement

There are two different workflow systems that the surgeon can select; the enhanced femoral workflow or the express femoral workflow. The enhanced workflow uses the Mako robotic device to guide femoral and acetabular bone resection and implant positioning, whereas the express workflow is more focused on the acetabular ­component. In this chapter, the enhanced workflow using the posterior approach is discussed. First, the acetabular array is set up, and placement should be considered to ensure it does not move during or impede bone resections. Bone pins are inserted either percutaneously with stab incisions or by making a small incision to visual-

ise the insertion and to reduce the thermal injury to the skin as we observed in our experience (Fig. 39.3). These pins should be inserted into the iliac crest as anterior as possible using the designated guide. The pelvic array is then assembled and inserted onto the bone pins 5 mm away from the skin and facing the camera. Second, the hip is accessed via the posterior approach, and prior to dislocation, a femoral cortical screw is inserted to accommodate the femoral array. Optimal positioning is over the anterior aspect of the greater trochanter in an area which allows unhindered internal and external rotation of the leg and should be engaged sufficiently to prevent toggling of the

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array which would compromise accuracy. In addition, a femoral checkpoint is placed alongside this. Bone registration can now begin using the calibration probe, which in itself is an optical array. First, with gross registration, the overall

femora-acetabular orientation is calibrated using the large checkpoints and placement of the probe tip into the divots and specified landmarks. Then fine registration using a number of smaller checkpoints which map the osseous anatomy of both the femur and acetabulum to the preoperative CT scan is performed. This occurs with the hip dislocated, to ensure adequate capturing of both acetabular and femoral checkpoints. This process is outlined in Fig. 39.4. The calibration probe can also be used to plan the femoral neck cut, based on preoperative femoral stem planning, the level is marked using diathermy, and then the osteotomy is manually performed (Fig.  39.5). The osteotomy level can be verified again using the probe. At this point, either the femur can be continued to be prepared, or the surgeon can proceed to the acetabulum, dependent on preference. The acetabulum is exposed circumferentially in a standard way. The acetabular registration screw is inserted into the superior acetabulum 1  cm superior to the acetabular rim and in an oblique direction to avoid cutting out during

Fig. 39.3  Percutaneously inserted bone pins for the acetabular array

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Fig. 39.4 (a) The intraoperative set up of the femoral array through a posterior approach (b) The on screen intraoperative instructions for femoral array positioning

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Fig. 39.5 (a) Intraoperative planning and marking of the femoral neck but prior to manual resection (b) Performing intraoperative fine femoral registration

reaming. A number 1 Vicryl suture is wrapped around the screw to aid removal and avoid retention of foreign material. The probe is inserted into the screw to complete the acetabular checkpoint registration process, and fine registration is performed in the same manner as the femur. The femoral canal may be prepared at this point in a standard way using the designated broaches until the desired trial size is reached as guided by the preoperative planning and intraoperative clinical assessment. The final trial may be left at this point and the desired neck attached (127° versus 132° neck). At this point, the femoral stem version can be verified using the probe again and this can be adjusted intraoperatively if required.

39.2.3 Bone Resections Following completion of the registration process, the bone resections can begin. The acetabulum or femur can be prepared first based on the preoperative plan and surgeon preference. The Mako system allows for two different acetabular reaming techniques; a single or multiple reaming technique dependent on surgeon preference. The multiple reamer technique allows the surgeon to deviate slightly from the preoperative plan while maintaining the planned centre of rotation.

Sequential reaming is performed using the Mako robotic-assisted arm, which provides haptic feedback to ensure the surgeon stays within a predefined stereotactic ‘cone,’ thus ensuring the planned inclination and centre of rotation are achieved. The stereotactic boundary does not allow the reamer to move if it is 15° outside of the planned position; however, these boundaries can be manually overridden should the surgeon feel it required. The on-screen display shows the CAD template with required bone resections highlighted in green. This provides a visual guide, which in conjunction with haptic feedback provided by the robotic-assisted arm allows the surgeons to accurately perform bone resections to the specified preoperative plan. Live on-screen information regarding the cup version and inclination, as well as resection margins left to be cut, is displayed, allowing highly precise resections to be carried out (Fig. 39.6).

39.2.4 Fine-Tuning and Definitive Implant A principle advantage of R-THA and the Mako system is the ability to fine-tune bone resections and implant positioning intraoperatively, using live data displayed on screen. With regard to the acetabulum, the stereotactic boundaries can be extended if required, and alteration of the version

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Fig. 39.6 (a) Reamer attached to robotic-assisted arm. assisted arm. Live on-screen measurements to guide ver(b) Reamer in defined position as guided by preoperative sion and inclination is seen plan and subsequent haptic feedback through robotic-­

and inclination performed if clinically required based upon on-table anatomy. These changes can be virtually templated intraoperatively to assess their effect prior to performing the resections. Following broaching of the femur, the broach tracking feature can be used to assess the femoral version, leg length, and offset with the final broach in situ. This allows the surgeon to make intraoperative decisions regarding implant position and based on the femoral stem anteversion, the acetabular anteversion can be changed to achieve the desired combined anteversion for the patient using the systems’ patient-specific ranges. The surgeon then accepts the final position and the system saves these figures for reference when inserting the definitive implants. Prior to insertion of the definitive implant, a trial reduction can be performed. The final alignment of the offset, combined anteversion, and leg length can be checked both clinically and using the optical motion capture technology which provides figures for degrees of version and millimetres for leg length. If the surgeons accept this position, the definitive components can then be inserted as per the manufacturers’

surgical technique. It should be noted that the Mako is a closed robotic system, meaning it is presently designed only for use with Stryker components including the Accolade or Exeter stems. However, some R-THA systems are open, allowing a wider variety of implants to be used.

39.3 Accuracy of Implant Position Traditional hip arthroplasty techniques have struggled to achieve consistent, reproducible results in terms of accurate implant position and the restoration of native hip biomechanics [18, 26–28]. Inaccurate implant positioning and the impact of this on hip biomechanics is the leading cause of instability [18, 26, 29]. The UK National Joint Registry data have found instability to be the main complication in both primary and revision hip arthroplasty in the first 12 months post-­operatively [1]. The traditional method of selecting an implant position which will ultimately be stable is using the techniques described by Lewinnek et  al. This work describes safe zones for acetabular cup posi-

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tioning of anteversion of 15° ± 10° and lateral opening of 40°  ±  10° associated with a 1.5% risk of dislocation [18]. Achieving a final implant position within these safe zones is challenging in M-THA.  Studies have shown that distorted anatomical landmarks, pelvic tilt, and inaccurate or poorly reproducible alignment guides can all contribute to final implant positioning being outside of the safe zones [18, 30]. In contrast, R-THA uses intraoperative femoral and acetabular bony landmarks and a bone registration process to orientate the robot to the intraoperative position of pelvis and hip. This reduces the margin for error when achieving the final implant position in accordance to the preoperative plan. Multiple studies have shown that R-THA systems are able to more accurately achieve a final acetabular position within the desired safe zones in comparison to conventional techniques [30–33]. The femoral implant position relies largely on manual broaching; however, the enhanced femoral workflow allows intraoperative assessment of trial implant anteversion, detecting retroversion and allowing for correction up to 15° of anteversion as required [34].

39.4 Accuracy of Restoring Hip Biomechanics Restoration of hip biomechanics is a challenging aspect of THA. Studies have shown that adverse outcomes are seen when the centre of rotation is shifted medially by >5mm or superiorly by >3mm [35]. R-THA uses a preoperative CT scan to create a 3D plan of the optimal acetabular and femoral bone resection levels. R-THA systems control the acetabular reaming depth to achieve the planned centre of rotation and hip offset [4, 5]. Dependent on the type of robotic system (semi-active or passive), the system will either aid marking the femur for manual femoral resection or autonomously perform the femoral resection. Kayani et al. in a prospective cohort study reported that R-THA was associated with improved accuracy in restoring the native horizontal (p 5°). Typical feature of uncemented cups is presence of extensive osteolysis/lucency in a well-fixed cup which is osseointegrated [91]. Special attention should be paid to the position of femoral head in metal-on-poly bearing THA, because eccentric head can often be visualized which depicts PE insert wear and helps in confirming the diagnosis of osteolysis [92]. Lysis or loosening due to infection should be ruled out on a radiograph because the planning of revision surgery changes drastically. Unlike osteolysis due to article disease, osteolysis in infection is quite aggressive with larger osteolytic areas progressing faster and inducing periosteal reaction. But low-grade infection generally mimics aseptic loosening radiologically [93].

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40  Modes of Failure in Total Hip Arthroplasty

CT scan is rarely required and can be done in cases where radiolucencies are subtle and difficult to interpret. MRI is useful to visualize pseudotumours and abductor muscle damage due to metallic wear particle (trunionosis/MOM THA). Specific radiological presentations of different modes of THA failure have been discussed in respective sections [94].

40.6 Prevention Since aseptic loosening is the most important cause limiting the long-term survival of prosthesis, prevention of loosening significantly reduces the revision risk especially in the younger population undergoing THA.  All efforts are directed

towards reducing the generation and dissemination of wear particles, which are responsible for the catastrophe [95]. Patient characteristics that increase wear generation and hence osteolysis are non-modifiable, i.e. the age at surgery and male gender. Higher activity level and body mass index, though implicated often, have not been proven to contribute. Surgical errors should be avoided to prevent accelerated wear and experience has been shown to be associated with this. Finally, implant factors play a major role [96] (Table 40.4). After osseointegration of the implant, the interface is almost entirely filled with bone. Failure in osseointegration results in fibrous tissue at the bone–implant interface, resulting in low strength and loosening of the implant [97].

Table 40.4  enumerates the risk factors and preventive steps for prosthesis loosening Patient factors Non-modifiable factors: • Male and young patients are at higher risk Modifiable factors: • Reduce body weight • Avoid high-impact activities Stop smoking Surgical technique factors

Achieve good surgical exposure to avoid prosthesis mal-positioning Avoid anterior approach to the hip if exposure is difficult Achieve good primary fixation of implants but Avoid excessive rasping and drilling Ensure stability of components

Ensure acetabular bone coverage >60% and proper orientation of prosthesis Prevent trunnionosis

Indirectly related to increased activity level which increases wear rate

To reduce prosthetic load and the risk of trunnionosis Smoking prevents osseointegration

These factors are decided by the surgeon and hence needs surgical experience. A study in 1990 concluded that surgeons performing >60 hip replacements per year have lower failure risk Many studies report higher risk of mal-­positioning leading to aseptic loosening and revision surgery when anterior approach is used

A well-fitting implant should have less than 50–150 μm gap to reduce fibrous tissue and promote osseointegration. Excessive rasping/drilling causes thermal necrosis of endosteum and inhibits bone ongrowth Besides the ideal gap, bone ongrowth/ingrowth micromotion between bone and implant of up to 30 μm. Unstable implants having motion over 150 μm may discourage osseointegration of the implant Placing the cup in 45 inclination and 15–20 anteversion avoids edge loading which decreases PE wear. This placement also gives enough coverage for bone growth Trunnion should be cleaned with saline solution and dried with gauze before assembling the head. This increases the disassembly forces Strike the head only with an impactor, to prevent point loading and bearing damage Two hammer blows, first as alignment blow and second as definitive impaction blow, ensure optimal impaction. No use of multiple light blows as the effect is not cumulative, but depends on the blow with highest energy Use a heavy hammer (500 g) to ensure impaction force of atleast 4000 N continued

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Table 40.4 (continued) Reduce third body wear For cemented THR, ensure adequate cementing

Implant factors Cementless components should have porous coating or HA coating Cementless femoral stems: Design and size

Reduce potential sites of wear Reduce effective joint space by blocking dissemination of wear particle

Ensure that there is no third body contamination during surgery 1. Do not ream and over-broach the femoral canal as it leaves smooth inner cortex which does not interdigitate well with cement 2. Use second- or third- generation cementing technique because:  • Distal canal plug improves pressurization of cement and ensures uniform mantle  • Pulsatile lavage removes loose fat and bone which improves cement penetration into the bone  • Vacuum mixing of cement decreases its porosity and as a result increases tensile and fatigue strength  • Stem centralizers (proximal and distal) help in maintaining a uniform circumferential cement mantle around the stem All acetabular cysts should be curetted, cleaned, and grafted. Place anchor holes into the bone to improve long-term fixation Osseointegration is promoted if pores have concave shape, wide pore throats, 150–600 μm size and > 40% porosity Type 1,2, and 4 stems are reported to have better survival. Modular and short stems have more revision risk Avoid modular stems because junctions are potential sites of wear As reported by Bergin et al., patients with larger stem sizes and lower bone to stem ratios had more stable implants Avoid using modular stems, modular neck, acetabular screws Improve liner locking mechanism (PE liner in metal cup) Implant acetabular shell without using screws Use proximally coated uncemented stems Use a tapered stem like Exeter stem which subsides into a centralizer and blocks off any potential implant-cement space

Type of polyethylene liner Use highly cross-linked PE (HXLPE) rather than UHMWPE: Gamma irradiation introduces crosslinking of polymer chains which resist abrasive and adhesive wear, commonly seen in THA Introduce oxidation resistance: Free radical oxidation during irradiation deteriorates mechanical properties. So oxidation resistance is achieved by annealing and remelting in first generation and sequential irradiation and using natural antioxidants (vitamin E) in second-generation HXLPE Prevent shelf ageing: Improved packaging stops diffusing back of oxygen into the PE through the packaging and prevents oxidation of residual-free radicals Type of bearing Avoid metal-on-metal THA Ceramic has the best wear characteristic Thickness of PE liner Very thin liner (30 mm), centering, and pedestal (i) Presence of obstacles like screws, cerclage wires, and internal fixation material (j) Potentially difficult or high-risk dislocation.

(a) Overhang distance (A) (b) Distance of lateral edge of implant to lateral edge of greater trochanter (B) (c) Overhang ratio (A/B) (d) Implant medial calcar prominence (C) (e) Anterior cortex distance to implant (D) (f) Posterior cortex distance to implant (E) (g) Eccentricity ratio (D/E)

Kwon et al. [9] have described five radiological parameters and two ratios for identification of potential risk factors for intraoperative fractures during endofemoral extraction of well-fixed stem (Fig. 43.1).

Approaches that are difficult to extend are best avoided. Ideal surgical approach should not compromise ability to carry out revision of both acetabular and femoral components if the situation may arise. Thus, anterior-based approaches

43.5 Technique of Stem Extraction 43.5.1 Surgical Approach

Fig. 43.1  Radiological parameters to assess potential risk factors for intraoperative fractures during endofemoral extraction of femoral stem

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Fig. 43.2 Armamentarium for stem removal: (1) SS wire; (2) Steinmann pin; (3) Broad Plier; (4) SS wire cutter; (5) Nose plier; (6) SS wire holder; (7) SS wire bender; (8) SS wire passer; (9) Thin flexible osteotomes; (10)

Burrs; (11) Stem extractor; (12) Stem extraction slap hammer; (13) Reverse hook; (14) Gouge; (15) Cement splitter; (16) Long pituitary grabber

which are generally considered good for uncomplicated femoral component revision may not be a good choice if both femoral and acetabular components need unexpected revision. Posterior Approach: Posterior approach carries advantages such as avoidance of damage to abductors and anterior neurovascular structures. The only disadvantage is the risk of dislocation which can be mitigated with meticulous posterior capsule and external rotator repair during closure. The extensile nature and familiarity to surgeons make this approach a preferred approach for revision cases [10]. Anterolateral approach: This approach also carries the extensile nature and familiarity to surgeons, but it carries disadvantage of partial detachment of gluteal muscles which can lead to weakness in abductors and instability later on. Good visualization of the area to work upon is essential for successful extraction of femoral component. After exposing hip with surgeon’s preferred approach, the hip is dislocated for removal for femoral head. The implant-bone interface at proximal femur should be well exposed all around

by removal of soft tissue at the interface, especially at lateral shoulder and over medial calcar with the help of cautery. Next step is to carefully remove any overhanging bone or cement at lateral shoulder of the implant which may impede removal of stem and become potential cause of fracture at greater trochanter during implant removal. This can be achieved with use of rongeurs or high-speed burr.

43.5.2 Cemented Stem Extraction As compared to uncemented stems, removal of cemented femoral stem is generally easier. Among cemented stems, polished stems are easier to extract than textured or collared stems. The general steps for removal of a well-fixed cemented stem involve disruption of implant-­ cement interface and removal of stem followed by removal of cement mantle. The armamentarium for removal of a well-fixed cemented stem shall include instruments depicted in Fig. 43.2. Absence of bonding between implant and cement in case of polished stems makes stem

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removal a relatively easy task. Usually just removal of overhanging bone or cement in the region of lateral shoulder and medial calcar followed by gentle backward blows with help of universal or implant specific extractor is sufficient for polished stem removal. On the other hand, disruption of implant-cement interface in case of textured, pre-coated, or porous-coated cemented stems might demand use of thin osteotomes in the metaphyseal region. Sharp instruments must be used with care not to perforate cortex.

C. S. Sonawane and M. M. Kulkarni

43.5.2.2 In Cement Revision Some studies have reported good outcomes using cement in cement technique if correct patient selection is done [12, 13]. Good proximal bone stock along with adequate cement mantle is important for a successful cement in cement revision.

43.5.3 Cementless Stem Extraction

43.5.2.1 Endofemoral Cement Extraction Once the stem is removed, the next step is to remove cement mantle. Removal of all cement mantle is recommended as persistence of cement mantle may misguide reamers leading to extramedullary stem placement. A variety of instruments can be utilized for cement removal. Moreland cement removal osteotomes, gouges, cement splitters, reverse hooks, and long pituitary grabbers are to name a few (Fig. 43.3). Removal of distal cement plug may require drilling through plug proximal to distal with help of big drill bit enough to allow passage of reverse hook for removal through canal. Alternatively, a separate window can be made in distal femur to reverse hammer with help of conical tap and hammer. Devices which use ultrasonic energy such as OSCAR (Orthosonic, Upper montclair, NJ) and Ultradrive (Biomet, Warsaw, IN) have also proven to be efficient and safe for removal of cement mantle or cement plug [11].

The general principles of extraction in uncemented stem are more or less same as in cemented stem. Achieving de-bonding at bone-implant interface is critical. The extent of osteointegration of a stem with bone varies with the extent of porous coating. In general, more the area of osteointegration, more difficult will be the stem extraction. Fully porous-coated stems are more difficult to remove than proximally coated stems. The length and geometry of stem can also influence the difficulty in extraction [14]. Good general visualization of the proximal part of the stem is essential for successful stem extraction. Any prominent bone or soft tissue over lateral shoulder is removed. Anterior, p­ osterior, medial, and lateral bone-implant interfaces at the proximal end of stem are well visualized. In case of stems with a collar, a limited horse-­shoe-­shaped osteotomy just below the collar or removal of collar using carbide drills may be necessary. De-bonding at bone-implant interface is started proximally with help of thin flexible osteotomes or pencil tip burrs in metaphyseal region (Fig. 43.4).

Fig. 43.3 (a) Reverse hook; (b) Gouge; (c) Cement splitter; (d) Long Pituitary Grabber

Fig. 43.4 (a) Thin flexible osteotomes. (b) Burrs

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43.6 Extended Trochanteric Osteotomy (ETO) If endofemoral extraction of femoral stem is not possible because of either a well-fixed stem or varus remodelling of femur, then removal of femoral stem can be achieved using Extended Trochanteric Osteotomy (ETO). ETO can also be used for thorough removal of cement after removal of cemented stem. The current form of extended trochanteric osteotomy technique used was first described by Younger and Paprosky [16]. When performed, an ideal ETO should be of adequate length to achieve the intended task of either femoral stem or cement removal, should allow space for at least two cables to be used for fixation of ETO, and should retain at least 4–6 cm of femoral diaphyseal fixation zone for revision femoral component [17].

43.6.1 Technique of ETO

Fig. 43.5  Steinmann pin technique as described by Shah et al.

Once the flexible osteotomes have been passed all around stem in metaphyseal region, stem can be extracted with gentle retrograde blows with help of implant-specific extractor or with universal extractor. In case of fully coated stems with osteointegration along whole length of the stem, long slender flexible osteotome which can reach almost to the distal part of stem should be used. Another technique described by Shah et al. [15] using 2 mm steinman pins under C-arm guidance can be tried. (Fig. 43.5). In case of persistent difficulty, one must look closely at the x-rays to find out pedestal causing problems. In presence of pedestal, one may have to seek extensile approach.

ETO is most commonly performed through traditional posterior approach. Standard posterior exposure is done through skin, subcutaneous tissue, through fascia lata, and short external rotators. Hip is now placed in extension and internal rotation with knee in flexion in an order to avoid tension on sciatic nerve. Gluteus maximus tendon can be released to allow mobilization of femur. Posterior border of vastus lateralis is identified and its muscle belly is mobilized anteriorly with the help of hohman retractor. Care should be taken to limit soft tissue stripping in an order to preserve vascularity at intended ETO site. The desired length of osteotomy is marked with electrocautery. Using multiple drill holes in a linear fashion using pencil tip burr or 2  mm K-wires, Osteotomy is begun at base of greater trochanter in sagittal plane going distally taking care to stay just lateral to linea aspera (Fig. 43.6). When reached at desired length of ETO, Distal lateral limb of ETO is done upto one third of femoral circumference and corners are rounded in an order to avoid stress riser. Uncontrolled femoral shaft fracture propagation distal to ETO length

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Fig. 43.6  Multiple drill holes made using pencil tip burr or 2 mm K-wire

C. S. Sonawane and M. M. Kulkarni

Fig. 43.8  ETO fixation using SS wires or cables

43.7 Broken Stem Removal

Fig. 43.7  Completing ETO using multiple osteotomes

can be prevented by placing a prophylactic cable 1 cm distal to intended ETO length. All the drill holes in vertical limb are now connected with the use of an oscillating saw. The direction of saw in proximal portion near greater trochanter should be angled medially to release entire greater trochanter along with ETO. Using multiple wide osteotomes, a controlled fracture is created by levering osteotomy site posterior to anterior hinging upon anterolateral periosteum and muscle. Greater trochanteric fragment can be retracted with attached abductors and vastus lateralis after releasing pseudocapsule present on the anterior aspect of greater trochanter (Fig. 43.7). With osteotomy retracted, femoral stem, cement, and bony pedestal removal is done under direct vision decreasing the chances of perforation. Reduction and fixation of osteotomy is done using at least two cables for the trochanteric region (Fig. 43.8).

About 1% of revisions after primary total hip replacement are due to fractured femoral stem [18, 19]. Owing to lack of any standard extraction device that can be applied to distal fragment, it can be a challenging task to remove a broken femoral stem especially if the distal broken component is well fixed [8]. Most commonly used technique to retrieve the broken fragment is to access full length of the broken stem using ETO. Using ETO precludes use of any standard length of femoral stem for revision but further distally fitting stems with or without distal locking mechanisms [8, 20, 21]. Moreland et al. [22] described creation of distal cortical window for retrograde removal of broken fragment as another option. If removal of distal broken femoral stem piece is difficult despite good exposure through ETO, longitudinal drilling along stem using 2 mm K-wires to break implant-bone or implant-cement interface can be done. Another option is to use hollow trephines to drill around the broken fragment. A recess in proximal face of distal broken fragment can be made using a carbide drill bit. This recess can be used to anchor a suitable threaded extraction device to take out the broken fragment [23].

43.8 Summary Thorough preoperative assessment in the form of x-rays can help surgeon anticipate difficulties during femoral stem removal surgery. If used

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11. Gardiner R, Hozack WJ, Nelson C, Keating EM.  Revision total hip arthroplasty using ultrasonically driven tools. A clinical evaluation. J Arthroplasty. 1993;8:517–21. 12. Lieberman JR, Moeckel BH, Evans BG, Salvati EA, Ranawat CS.  Cement-within-cement revision hip arthroplasty. J Bone Joint Surg. 1993;75:869–71. 13. Mandziak DG, Howie DW, Neale SD, McGee MA. Cement-within-cement stem exchange using the collarless polished double-taper stem. J Arthroplasty. 2007;22:1000–6. 14. Edwards P, Barnes C. Removal of a well-fixed femoral References stem: tour de force. Semin Arthroplast. 2014;25:159– 68. https://doi.org/10.1053/j.sart.2014.04.014. 1. Schwartz AM, Farley KX, Guild GN, Bradbury 15. Shah RP, Kamath AF, Saxena V, Garino JP. Steinman TL.  Projections and epidemiology of revision hip pin technique for the removal of well-fixed femoral and knee arthroplasty in the United States to 2030. stems. J Arthroplasty. 2013;28:292–5. J Arthroplast. 2020;35(6):S79–85. https://doi. 16. Younger T, Bradford M, Magnus R, Paprosky org/10.1016/j.arth.2020.02.030. W.  Extended proximal femoral osteotomy: a new 2. Bohl DD, Samuel AM, Basques BA, Della Valle CJ, technique for femoral revision arthroplasty. J Levine BR, Grauer JN. How much do adverse event Arthroplasty. 1995;10(3):329–38. rates differ between primary and revision total joint 17. Weeden S, Paprosky W.  Minimal 11-year follow-up arthroplasty? J Arthroplast. 2016;31:596–602. of extensively porous-coated stems in femoral revi3. Isaacson MJ, Bunn KJ, Noble PC, Ismaily SK, sion total hip arthroplasty. J Arthroplast. 2002;17(4 Incavo SJ. Quantifying and predicting surgeon work Suppl 1):134–7. input in primary vs revision total hip arthroplasty. J 18. Khatod M, Cafri G, Inacio MCS, Schepps AL, Paxton Arthroplast. 2016;31:1188–93. EW, Bini SA. Revision total hip arthoplasty: factors 4. Bunn KJ, Isaacson MJ, Ismaily SK, Noble PC, Incavo associated with re-revision surgery. J Bone Joint Surg SJ.  Quantifying and predicting surgeon work effort Am. 2015;97(5):359–66. https://doi.org/10.2106/ for primary and revision total knee arthroplasty. J JBJS.N.00073. Arthroplast. 2016;31(9 Suppl):59–62. 19. Clohisy JC, Calvert G, Tull F, McDonald D, Maloney 5. Nichols CI, Vose JG.  Clinical outcomes and costs WJ. Reasons for revision hip surgery: a retrospective within 90 days of primary or revision total joint review. Clin Orthop Relat Res. 2004;429:188–92. arthroplasty. J Arthroplast. 2016;31:1400–1406.e3. https://doi.org/10.1097/01.blo.0000150126.73024.42. 6. O’Neill DA, Harris WH.  Failed total hip replace- 20. Younger TI, Bradford MS, Magnus RE, Paprosky ment: assessment by plain radiographs, arthrograms, WG.  Extended proximal femoral osteotomy. A and aspiration of the hip joint. J Bone Joint Surg Am. new technique for femoral revision arthroplasty. 1984;66(4):540–6. J Arthroplast. 1995;10(3):329–38. https://doi. 7. Engh CA, Massin P, Suthers KE.  Roentgenographic org/10.1016/S0883-­5403(05)80182-­2. assessment of the biologic fixation of porous-­surfaced 21. Wagner M, Wagner H. The transfemoral approach for femoral components. Clin Orthop Related Res. revision of total hip replacement. Orthop Traumatol. 1990;257:107–28. 1999;7(4):260–76. 8. Laffosse JM.  Removal of well-fixed fixed femo- 22. Moreland JR, Marder R, Anspach WE Jr. The winral stems. Orthop Traumatol Surg Res. 2016;102(1 dow technique for the removal of broken femoral Suppl):S177–87. https://doi.org/10.1016/j. stems in total hip replacement. Clin Orthop Relat Res. otsr.2015.06.029. Epub 2016 Jan 18. 1986;212:245–9. 9. Kwon YM, Antoci V, Eisemon E, Tsai TY, Yan Y, 23. Wroblewski BM.  A method of management of the Liow MHL. “Top-out” removal of well-fixed dual-­ fractured stem in total hip replacement. Clin Orthop taper femoral stems: surgical technique and radioRelat Res. 1979;141:71–3. graphic risk factors. J Arthroplast. 2016;31:2843–9. 10. Padgett DE, Lewallen DG, Penenberg BL, et  al. Surgical technique for revision total hip replacement. J Bone Joint Surg Am. 2009;91(suppl 5):23–8.

with patience, various surgical techniques described in literature can help achieve femoral stem removal without much bone loss or complications like intraoperative fractures. When necessary, surgeon must make use of extensile approach like extended trochanteric osteotomy to achieve femoral stem removal.

Implant Selection in Revision Total Hip Arthroplasty

44

Praharsha Mulpur, A. B. Suhas Masilamani, and A. V. Guravareddy

44.1 Introduction Total hip arthroplasty (THA) is one of the most successful orthopaedic surgeries till date. Total hip arthroplasty has evolved significantly over the past few decades, with improvement in our understanding of hip biomechanics, surgical approach, and material science behind design and manufacture of THA prostheses. Registry data are essential in understanding the epidemiology of primary and revision THA. Gwam et al. [1] reported 50,000 revision THA surgeries annually in the USA and the burden of revision THA is projected to double by 2026. Kurtz et al. [2] reported a potential and massive 174% increase in the burden of primary THA by 2030 in the USA. Mittal et al. [3] studied the epidemiology of revision THA at a high-volume center in India, with a reported burden of 21% of revision procedures. The most common etiologies requiring revision THA are aseptic loosening, osteolysis, infection, instability, stress shielding, mechanical failure, and periprosthetic fracture. Mittal et  al. [3] reported infection to be the leading cause of revision in their experience. Bozic et  al. [4] reported findings of an investigation (The Healthcare Cost and Utilization Project, using the

P. Mulpur (*) · A. B. Suhas Masilamani A. V. Guravareddy Sunshine Bone and Joint Institute, Sunshine Hospitals, Hyderabad, India

nationwide in-patient database in the USA), wherein all-component revision accounted for 41.1% of all revision THA performed. Instability/ Dislocation was the most common indication for revision THA (22.5%), aseptic loosening (19.7%), and infections in 14.8%. The purpose of this chapter is to simplify the decision-making process for implant selection in revision THA. The ultimate goal of revision THA surgery is to restore optimal hip biomechanics and achieve durable fixation of components. Factors influencing implant selection include etiology behind revision surgery, bone loss on the femoral and acetabular bone-implant interfaces, and availability of the appropriate implants for revision.

44.2 Implant Selection for Revision of the Femoral Component The main challenge in revision THA is to achieve stable and durable fixation of components to ensure excellent survivorship. In almost all cases of revision THA, the surgeon is faced with challenges of managing bone loss around the femoral or acetabular components. It is important to characterize and classify bone defects around prostheses to choose the right implant for revision. A good classification system should be easy to implement and should be reliable and reproducible, with good inter- and intra-observer agree-

© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_44

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ment. More importantly, the classification system used should be clinically useful and help in management decisions and help in prognostication. The Paprosky Classification system [5, 6] is the most widely accepted and used system for bone defects around the femur and acetabulum. In this section of the chapter, we will reference only the Paprosky bone loss classification around the femoral component.

44.2.1 Paprosky Classification of Bone Loss Around the Femoral Component [5] Femoral bone loss is classified into four subtypes based on three findings. 1. Location of bone loss in the femur— Metaphyseal versus diaphyseal 2. Extent of supportive bone remaining in the metaphyseal region 3. Amount of bone remaining in the isthmus region for diaphyseal fixation of the revision stem. The Paprosky Classification is summarized in Table 44.1. Femoral component revision can be classified according to the type of fixation used: (a) Uncemented Revision (b) Cemented Revision

Uncemented revision can be broadly subclassified based on stem characteristics: (a) Proximally porous-coated femoral stems (most primary THA stems fall in this category) (b) Uncemented and proximally modular femoral stems (c) Extensively porous-coated femoral stems (d) Tapered stems I. Modular tapered stems II. Non-modular tapered stems Implant selection based on degree of bone loss:

44.2.2 Paprosky Type I Bone Loss Characterized by minimal cancellous bone loss in the metaphysis with intact diaphyseal bone. This type of bone loss is of rare occurrence and is seen in cases of failure of bone ingrowth in proximally coated uncemented stems or poorly inserted cemented femoral stems lacking good contact. This is similar to cases of mechanical loosening, with relatively intact bone stock. Mild bone loss that occurs during femoral component explantation may present in this fashion. Since there is cancellous bone in the metaphysis and no remodeling, the implant of choice could be any cemented or uncemented stems of standard length, which are routinely used in primary THA (Figs. 44.1 and 44.2).

Table 44.1  Paprosky Classification of Bone Loss around the femoral component in revision total hip arthroplasty Type I II IIIA

IIIB

IV

Definition Minimal metaphyseal bone loss in proximal femur Moderate to severe metaphyseal bone loss in proximal femur Severe metaphyseal bone loss in proximal femur, diaphysis intact for a short distance Severe metaphyseal bone loss in proximal femur, diaphysis intact for a short distance Complete loss of metaphyseal and diaphyseal femoral bone stock

Metaphysis Intact

Diaphysis Intact

Proximal femoral remodeling None

Deficient/absent

Intact

Slight

Deficient/absent

4 cm or more of isthmus intact

Significant

Deficient/absent

4  cm of remaining isthmic bone amenable for distal fixation, whereas type IIIB has 50% host bone contact. These cases are also managed with cementless cups, with additional stability through screw fixation and impaction bone grafting (Fig.  44.14). Bone grafting is more important in Type IIC defects which are associated with medial bone loss (Fig. 44.15). In the above types of bone loss, there is adequate host bone stock to achieve primary or initial fixation of the acetabular shell.

Contraindications: Poor bone healing secondary to previous irradiation of the pelvis, unrecognized pelvic discontinuity, and host metabolic bone disorders which may affect bone formation and osseointegration.

44.5.2 High-Hip Center Reconstruction is possible using a high-hip center and a cementless shell. In cases of hip dyspla-

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sia, especially with the high riding hip, good bone is available only superiorly. High-hip center follows reaming into the false acetabulum in the ilium, with the shell supported by the intact bone of the ilium. The surgeon should anticipate smaller shell sizes in such cases.

cancellous bone. These implants are excellent for fixation and osteointegration. The increased porosity and similar material characteristics allow rapid and significant bone ingrowth after implantation. The augments provide initial stability and coverage for the acetabular component and also undergo osseointegration over time, providing greater stability. 44.5.3 Jumbo-Cup Principle These augments are available in various sizes and can be used in any part of the acetabulum. Jumbo cups are not special implants or not named Some companies like Zimmer offer modular as such. The jumbo-cup is a surgical principle reconstruction options, with modular augments. which is dependent on cementless acetabular Indications: When host bone contact is around components of larger diameters. The “jumbo-­ 50% with the component, augments are precup” was defined originally by the Mayo Clinic ferred. With porous metal augments, up to 30% group, by Whaley et  al. [13], as an acetabular of cup un-coverage can be accepted. Modular shell with outer diameter (OD) of 66  mm and augments are indicated when there is significant more in males and 62  mm or more in females. loss of the acetabular dome, large and irregular This is, however, based on the sizes in the bone defects that can compromise the stability of Caucasian population. They suggest that a cup the cup, and in the cases of pelvic discontinuity. size 10 mm more than the population average can Paprosky Type IIB defect with superolateral be considered as jumbo-cup. bone deficiency is best tackled with a wedge augJumbo-cups can be used in revision of Type II ment. Even for IIIB defects with bone loss supeand Type IIIA defects. There is adequate bone riorly, wedge augments are available, thus stock and continuity of the columns. converting an oval defect into a relatively hemiAdvantages: Easier to restore the native center spherical defect (Fig. 44.16). A case example is of rotation, increase surface area of contact illustrated in Fig. 44.17. between the shell and host bone, increased osseoLarger buttress augments are available which integration. The large size helps in distribution of can be fixed to the ilium and provide superior forces, thus reducing the chances of cup coverage to the shell (Fig. 44.18). migration. In the case of pelvic discontinuity, hemispherStudies [13–15] have demonstrated good sur- ical uncemented cups can be used with augments vivorship of large uncemented components (Jumbo cups) at long-term follow-up with acceptable rates of revision.

44.5.4 Trabecular-Metal Components and Augments Highly porous metal implants are now widely marketed and available and serve as an excellent implant choice in complex revision scenarios. The use is limited by the high costs involved. Tantalum is the metal used in the manufacture of highly porous cups and mainly acetabular augments. The material characteristics of tantalum (porosity and Young Modulus) are very similar to

Fig. 44.16  Diagram showing the use of trabecular metal wedge augment for reconstruction of superior acetabular defect in revision arthroplasty. Image courtesy Zimmer Inc.

44  Implant Selection in Revision Total Hip Arthroplasty

Fig. 44.17  Preoperative radiograph showing Paprosky Type IIIB defect of the acetabulum with the characteristic “Up-and-in” migration of the cemented Cup. Reconstruction was performed with impaction grafting of

Fig. 44.18  Buttress augments can be used to manage deficient bone stock of the acetabular columns. Image courtesy Zimmer Inc.

only with the Pelvic distraction technique. The reader is encouraged to go through the reference to familiarize with the surgical technique.

44.5.5 Use and Role of Oblong or Bilobed Implants for Revision The use of oblong cups is based on the principle of defect matching in revision THA. These cups rely only on native patient bone contact and are not used in conjunction with structural allograft. Indications: Superior acetabular rim defects of Paprosky Type IIB and IIIA. Design Rationale: As compared to hemispheric cups of the same superior-inferior

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the medial defect, trabecular porous metal augment for the superior defect, and highly porous uncemented acetabular component with additional screws

diameter, oblong cups are smaller in the mediolateral plane and also in the anteroposterior plane. This permits initial AP capture with the anterior and posterior columns without reaming it out. The higher superior-inferior dimension allows shape matching oval bone defects that are associated with superior rim or superolateral defects. Advantage: Cup can match the defect without disruption of bone-stock. Very little reaming is required. Disadvantage: Expensive, limited availability of these components. There are some studies with mid-term to long-­ term follow-up with 98% survival at 8 years follow-­up [16–18]. Overall, results are good, with low rates of revision for aseptic loosening. Bilobed Cups: These cups were originally designed for large Type II defects with loss of superior dome and superolateral rim of the acetabulum. The bilobed cup essentially functions like a combination of a hemispherical cup to restore center of rotation and another superior “lobe” which provides contact with host bone, in the defect, thus providing additional support. Studies have shown satisfactory mid-term to long-term survival of these implants. Maskal et  al. published good outcomes after use of these cups for large Type III defects also, especially IIIA with an “up and out” defect [19].

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Fig. 44.19  Diagram showing the use of a Cup-cage construct for the reconstruction of acetabular defect associated with pelvic discontinuity. Image courtesy Zimmer Inc.

44.5.6 Role of Cup-Cage Constructs This is a combination of cemented shell used in combination with an acetabular cage (Fig. 44.19). Indications: Type IIIA, IIIB and pelvic discontinuity. Though cages are indicated in the reconstruction of acetabulum in cases of pelvic discontinuity, Abolghasemian et  al. [20] published their outcomes of cup-cage constructs and found better outcomes compared to cages used alone.

44.5.7 Role of Tri-flange Reconstruction Use of structural allograft and modular porous metal augments, oblong cups, and jumbo cups are all examples of “defect matching”. In this, the surgeon aims to fill the residual defect after

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appropriate sizing of the acetabular shell, to improve fixation of the cup. The other technique is to perform a “Defect Bridging” technique. Indications: Large IIIA and IIIB defects require defect bridging. Advantages: These are patient-specific or custom-­fabricated implants and are sized anatomically to perfectly bridge the bone defect. The implant is fabricated based on 3D CT data obtained. The device can be manufactured either with metal porous-coating or hydroxy-apatite coating over titanium. The final uncemented biological fixation augmented by screws can be achieved with the ilium, ischium, and pubis. Design rationale: Sheth et al. [21] describe tri-­ flange devices as “rigid fixation” which help to heal the pelvic discontinuity as in the case of pelvic reconstruction plating for fractures. This is in contrast with other implants like cages or rings which are nonrigid types of fixation. Preoperative planning, assessment of bone defects, and implant selection are the foundation for a successful revision total hip arthroplasty. Surgeons need to be aware of the surgical techniques, along with their principles to choose the right procedure for the right scenario, to ensure optimal outcomes. An algorithmic approach to bone defect management is important. In their Instructional Course Lecture, Sporer et  al. laid down an excellent algorithm for the evaluation and management of acetabular bone loss during revision THA.  This is widely cited and followed, across the world (Fig. 44.20).

44  Implant Selection in Revision Total Hip Arthroplasty

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Type IIA (Cavitary defect) • Hemispherical cup No Is the hip center > 2cm above the native hip center?

Type IIB (Segmental defect 18  mm and L.  Effect of circumferential plasma-spray porous Paprosky Type IV defects. coating on the rate of femoral osteolysis after total hip arthroplasty. JBJS. 1999;81(9):1291–8. 17. Engh CA, O'Connor D, Jasty M, McGovern TF, Bobyn JD, Harris WH.  Quantification of implant microReferences motion, strain shielding, and bone resorption with porous-coated anatomic medullary locking femoral 1. Moon KH, Kang JS, Lee SH, Jung SR. Revision total prostheses. Clin Orthop Rel Res. 1992;285:13–29. hip arthroplasty using an extensively porous coated 18. Pilliar RM, Lee JM, Maniatopoulos CD. Observations femoral stem. Clin Orthop Surg. 2009;1(2):105–9. on the effect of movement on bone ingrowth into 2. Ballard WT, Callaghan JJ, Sullivan PM, Johnston porous-surfaced implants. Clin Orthop Rel Res. RC. The results of improved cementing techniques for 1986;208:108–13. total hip arthroplasty in patients less than fifty years 19. Jasty M, Bragdon C, Burke D, O'Connor DA, old. A ten-year follow-up study. J Bone Joint Surg Am Lowenstein J, Harris WH. In vivo skeletal responses Vol. 1994;76(7):959–64. to porous-surfaced implants subjected to small 3. Ranawat CS, Hansraj KK, Neves MC.  A seventeen induced motions. JBJS. 1997;79(5):707–14. year survivorship study of Charnley total hip replace- 20. Engh CA, Glassman AH, Bobyn JD. Surgical princiment. Clin Exp Rheumatol. 1989;7:S153. ples in cementless total hip arthroplasty. Tech Orthop. 4. Marya SK, Thukral R.  Extensively coated revision 1986;1:35–53. stems in proximally deficient femur: early results in 21. Meek RM, Greidanus NV, Garbuz DS, et al. Extended 15 patients. Indian J Orthop. 2008;42(3):287. trochanteric osteotomy: planning, surgical technique. 5. Sporer SM, Paprosky WG. Revision total hip arthroand pitfalls. Inst Course Lect. 2004;53:119–30. plasty: the limits of fully coated stems. Clin Orthop 22. Berry DJ, Maloney WJ. Master techniques in orthoRel Res®. 2003;417:203–9. pedic surgery, the hip, vol. 1. 3rd ed. Wolters Kluwer; 6. Weeden SH, Paprosky WG.  Minimal 11-year folUSA. 2016. p. 47–58. low-­up of extensively porous-coated stems in femo- 23. Hellman EJ, Capello WN, Feinberg JR. Nonunion of ral revision total hip arthroplasty. J Arthroplast. extended trochanteric osteotomies in impaction graft2002;17(4):134–7. ing femoral revisions. J Arthroplast. 1998;13:945–9. 7. Paprosky WG, Burnett RS.  Extensively porous-­ 24. Miner TM, Momberger NG, Chong D, et  al. The coated femoral stems in revision hip arthroplasty: extended trochanteric osteotomy in revision hip rationale and results. Am J Orthop (Belle Mead NJ). arthroplasty: a critical review of 166 cases at mean 2002;31(8):471–4. 3 year, 9 month follow-up. J Arthroplast. 2001;16(8 8. Jones RE.  Modular revision stems in total hip Suppl. 1):188–94. arthroplasty. Clin Orthop Rel Res (1976–2007). 25. Mardones R, Ginalez C, Cabanela ME, et  al. 2004;420:142–7. Extended femoral osteotomy for revision in hip 9. Hennessy DW, Callaghan JJ, Liu SS.  Second-­ arthroplasty: results and complications. J Arthroplast. generation extensively porous-coated THA stems at 2005;20:79–83. minimum 10-year followup. Clin Orthop Rel Res®. 26. MacDonald SJ, Rosenzweig S, Guerin JS, McCalden 2009;467(9):2290–6. RW, Bohm ER, Bourne RB, Rorabeck CH, Barrack

748 RL.  Proximally versus fully porous-coated femoral stems: a multicenter randomized trial. Clin Orthop Rel Res®. 2010;468(2):424–32. 27. Ahmet S, İsmet KÖ, Mehmet E, Eren Y, Remzi T, Önder Y.  Midterm results of the cylindrical fully porous-coated uncemented femoral stem in revision patients with Paprosky I–IIIA femoral defects. J Orthop Surg. 2018;26(2):2309499018783906. 28. Thomsen PB, Jensen NJF, Kampmann J, Hansen TB.  Revision hip arthroplasty with an extensively porous-coated stem—excellent long-term results also in severe femoral bone stock loss. USA. Hip Int. 2013;23(4):352–8. https://doi.org/10.5301/ hipint.5000032. Epub 2013 May 27 29. Waddell J, Baird R, Nikolaou V, Schemitsch E. Outcome of revision total hip arthroplasty using the echelon revision stem. In: Orthopaedic proceedings 2012 Jun (Vol. 94, No. Suppl. XXV, p. 6). The British Editorial Society of Bone & Joint Surgery. USA. 30. Chung LH, Wu PK, Chen CF, Chen WM, Chen TH, Liu CL.  Extensively porous-coated stems for femoral revision: reliable choice for stem revision in Paprosky femoral type III defects. Orthopedics. 2012;35(7):e1017–21. 31. Jayakumar P, Malik AK, Islam SU, Haddad FS.  Revision hip arthroplasty using an extensively porous coated stem: medium term results. Hip Int. 2011;21(2):129–35. 32. Engh CA Jr, Ellis TJ, Koralewicz LM, McAuley JP, Engh CA Sr. Extensively porous-coated femoral revision for severe femoral bone loss: minimum 10-year follow-up. J Arthroplast. 2002;17(8):955–60. 33. Hamilton WG, Cashen DV, Ho H, Hopper RH Jr, Engh CA.  Extensively porous-coated stems for femoral revision: a choice for all seasons. J Arthroplast. 2007;22(4 Suppl. 1):106–10. https://doi. org/10.1016/j.arth.2007.01.002. 34. Hamilton WG, McAuley JP, Tabaraee E, Engh CA. (Sr). The outcome of rerevision of an extensively porous-coated stem with another extensively porous-­ coated stem. J Arthroplast. 2008;23(2):170–4. https:// doi.org/10.1016/j.arth.2007.03.038. Epub 2007 Nov 26 35. Wallace CN, Chang JS, Kayani B, Moriarty PD, Tahmassebi JE, Haddad FS.  Long-term results of revision total hip arthroplasty using a modern extensively porous-coated femoral stem. J Arthroplast. 2020;35(12):3697–702. https://doi.org/10.1016/j. arth.2020.06.052. Epub 2020 Jun 25 36. Fu PL, Wu HS, Li XH, Qian QR, Wu YL, Zhu YL, Chen Y. The use of uncemented extensively porous-­ coated femoral components in the management of Vancouver type B2 periprosthetic femoral fractures. Zhonghua wai ke za zhi [Chinese J Surg]. 2009;47(3):181–4. 37. Egan KJ, Di Cesare PE.  Intraoperative complications of revision hip arthroplasty using a fully

M. Sharma et al. porous-coated straight cobalt-chrome femoral stem. J Arthroplast. 1995;(Suppl. 10):S45–51. 38. Callaghan JJ, Rosenberg AG, Rubash HE. The adult hip. 2nd ed. Lippincott Williams & Wilkins. USA. p. 1428–38. 39. Engh CA Jr, Young AM, Engh CA Sr, Hopper RH Jr. Clinical consequences of stress shielding after porous-coated total hip arthroplasty. Clin Orthop Relat Res. 2003;417:157–63. 40. Ding Z, Ling T, Mou P, Wang D, Zhou K, Zhou Z.  Bone restoration after revision hip arthroplasty with femoral bone defects using extensively porous-­ coated stems with cortical strut allografts. J Orthop Surg Res. 2020;15:1–9. 41. Huang Y, Shao H, Zhou Y, Gu J, Tang H, Yang D.  Femoral bone remodeling in revision total hip arthroplasty with use of modular compared with monoblock tapered fluted titanium stems: the role of stem length and stiffness. JBJS. 2019;101(6):531–8. 42. Paprosky WG, Greidanus NV, Antoniou J. Minimum 10-year-results of extensively porous-coated stems in revision hip arthroplasty. Clin Orthop Relat Res. 1999;369:230–42. 43. McAuley JP, Culpepper WJ, Engh CA.  Total hip arthroplasty: concerns with extensively porous coated femoral components. Clin Orthop Relat Res. 1998;355:182–8. 44. McAuley JP, Engh CA Jr. Femoral fixation in the face of considerable bone loss: cylindrical and extensively coated femoral components. Clin Orthop Relat Res. 2004;429:215–21. 45. Mokka J, Keemu H, Koivisto M, Stormi T, Vahlberg T, Virolainen P, Junnila M, Seppänen M, Mäkelä KT. Experience of structural onlay allografts for the treatment of bone deficiency in revision total hip arthroplasty. Scand J Surg. 2013;102(4):265–70. 46. Pak JH, Paprosky WG, Jablonsky WS, Lawrence JM.  Femoral strut allografts in cementless revision total hip arthroplasty. Clin Orthop Relat Res. 1993;295:172–8. 47. Barden B, Fitzek JG, Huttegger C, Löer F. Supportive strut grafts for diaphyseal bone defects in revision hip arthroplasty. Clin Orthop Relat Res. 2001;387:148–55. 48. Ding ZC, Ling TX, Yuan MC, Qin YZ, Mou P, Wang HY, Zhou ZK.  Minimum 8-year follow-up of revision THA with severe femoral bone defects using extensively porous-coated stems and cortical strut allografts. BMC Musculoskelet Disord. 2020;21:1–2. 49. Schwartz JT, Mayer JG, Engh CA. Femoral fracture during non-cemented hip arthroplasty. J Bone Joint Surg Am. 1989;71:1135–42. 50. Chappell JD, Lachiewicz PF. Fracture of the femur in revision hip arthroplasty with a fully porous-coated component. J Arthroplast. 2005;20(2):234–8.

Custom Prostheses for Acetabular Reconstruction in Revision Hip Arthroplasty

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David Hillier, Henry Wynn Jones, and Nikhil Shah

58.1 Introduction Major acetabular bone loss poses significant challenges to the revision hip surgeon, particularly those in which there is insufficiency of one (Paprosky 3A/3B, AAOS III) or both acetabular columns (pelvic discontinuity, AAOS IV). In this situation, obtaining adequate primary fixation and stability with standard hemispherical prostheses off the shelf are likely to be insufficient due to deficient or non-supportive acetabular columns, leading to ongoing micromotion and subsequent failure due to loosening. The primary stability of any press-fit, uncemented design of prosthesis relies on the integrity of the pubis and ischium to control micromotion and allow osseointegration, along with the ilium [1]. In cases where this bone is not available to support the hemispherical component, primary component stability cannot be achieved.

D. Hillier Liverpool University Hospitals, NHS Foundation Trust, Liverpool, UK e-mail: [email protected] H. W. Jones · N. Shah (*) Centre for Hip Surgery, Wrightington Hospital, Wigan, UK e-mail: [email protected]; [email protected]

58.2 Patho-Anatomy of the Acetabulum It is instructive to think of the acetabulum like a pelvic-acetabular trauma surgeon in addition to an arthroplasty surgeon. Our experience has been that familiarity with the management of pelvic and acetabular fractures provides the surgeon with transferable skills to address such extensive bone loss problems in revision arthroplasty. Letournel’s pioneering [2, 3] work was instrumental in developing the understanding of the anatomy and biomechanics of the acetabulum in relation to the bony anatomy of the pelvis. He conceptually described the acetabulum to be formed of two columns that are arranged like an inverted Y. The anterior column extends from the anterior iliac crest and incorporates the pecten pubis, going inferiorly and including the pubic bone. The part of this bone that forms the anterior aspect is referred to as the anterior wall. For an arthroplasty surgeon, this can be visualised from “inside” the acetabulum during reaming. The anterior inferior iliac spine and the root of the pubic ramus are bony structures that can be visualised and palpated by the arthroplasty surgeon exposing the acetabulum. Both these structures are important when one tries to get “anterior pinch” of the uncemented component. The posterior column is shorter and extends from the posterior ilium and the bone forming the greater sciatic notch inferiorly to the ischium.

© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_58

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This convex piece of bone contains the posterior superior part of the acetabulum and is again important in obtaining primary stability with an uncemented hemispherical component. Familiarity with acetabular trauma fixation techniques is an advantage in this type of acetabular reconstruction using custom components in our experience because it gives familiarity with the extensile surgical exposures as well as an understanding of the patho-anatomy [4–7].. It is also important to appreciate the location and proximity of the important soft tissue and neurovascular structures in relation to the acetabulum, especially the sciatic and femoral nerve, and the iliofemoral artery and vein. This knowledge and understanding are vital in preoperative planning and execution of safe surgery when one fixes the custom component with multiple screws to the remaining bone.

58.3 History and Evolution Management of acetabular bone loss has evolved over the years where surgeons have tried different strategies [1, 8–11]. A brief review helps in understanding the place of a custom component in this reconstructive ladder. In 1994, Paprosky [8] described the use of proximal femoral “arc” allograft screwed into the acetabular defect and supported by a pelvic reconstruction plate. In this series, all 6 of the 3B defects demonstrated ongoing loosening and migration, despite successful integration of the graft in 4 of the patients who underwent re-revision. In 1999, Dearborn and Harris reported their series of 46 hip replacements in which the placement of the uncemented acetabular component was deliberately high of the native hip centre, nestled within the acetabular defect and augmented with screws [9]. Mechanical failure at 10 years was 6%.

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The use of giant uncemented acetabular components was reported by Whaley et  al. [10]. In their series of 89 cases, they demonstrated a predicted re-revision rate at 8 years, for all causes, was 7%. Moreover, aseptic loosening was only noted in the combined cavitary and segmental defect group. None of these techniques are therefore suitable in cases with greater than 50% acetabular host bone loss and uncontained defects [12]. Where there is a defect in the supporting columns, restoration of bone stock is ideal for making future revisions easier [11]. However, the use of structural allograft needs to be supplemented with the use of an anti-protrusio cage or supportive ring that bridge from the ileum to the ischium [12–14]. Such cages were off-the-shelf products, produced in a range of sizes, selected for their best fit. They had three flanges that required bending appropriately intraoperatively before being screwed into the ileum and ischium. Into this construct is cemented a polyethylene cup. The problem with cages is a high risk of breakage, and failure due to loosening and instability. Also, the cage did not have any ingrowth potential to the host bone. A cage can be conceptualised to work as an “internal plate” in cases with pelvic discontinuity. Biomechanically this is inferior to fixation of the acetabulum with column plates [12–14]. Latterly, with the introduction of highly porous trabecular augments and cups, the “cup-­ cage” reconstruction technique has developed with less reliance on the structural allograft and its problems with reabsorption, leading to a reduction in the rates of aseptic loosening [15]. An ultraporous cup is applied to the acetabulum with screws and protected with a cage bridging from the ilium to the ischium. The role of the cage is to protect the construct till ingrowth has been achieved. In all these techniques, instability remains the most common method of failure and subsequent re-revision.

58  Custom Prostheses for Acetabular Reconstruction in Revision Hip Arthroplasty

58.4 The Need for a Custom Acetabular Component Once a deeper understanding of these concepts is gained, one can appreciate why the usual hemispherical uncemented components even with supplementary screws are unable to cope with extensive host bone loss with non-supportive acetabular columns and where there is acetabular discontinuity. A discontinuity can be thought of as an “acetabular fracture” where the superior fragment is “fractured” away from the inferior fragment. The columns become non-supportive. An uncemented component even with screws will not be able to reliably and predictably cope with “fixing” the discontinuity as an internal plate, and at the same time providing a stable arthroplasty [5–7]. This discontinuity can be either stiff or mobile in our experience. There can also be significant bone loss at the site of the discontinuity resulting in a “gap non-union.” With this pathology, an

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Fig. 58.1 (a–c) Showing acetabular reconstruction in 2 stages using column plate fixation and cementless reconstruction. (a) Aseptic failure with intra-pelvic migration of acetabular component. (b) Extraction of components,

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uncemented component is unable to reliably cope with “stabilising” the “nonunion” and providing a stable hip replacement. The available host bone is insufficient to provide reliable osseointegration. The reconstructive solution therefore needs to be able to “fix the nonunion” and provide a stable arthroplasty. In many of these cases with less extensive bone loss, we have been able to achieve this using the concept of “fix and replace” (borrowed from acetabular trauma surgery) where the acetabulum is first stabilised using column fixation and then an appropriate acetabular component with supplementary screws can be stably fixed to the reconstructed columns (Fig.  58.1). This philosophy can be used in one or two stages [4–7]. However, in more extensive bone loss, reliable fixation cannot be obtained even using plates. The appropriate solution therefore consists of a bridging implant that does the dual function of bypassing the defect by fixation from

c

bone grafting and fixation of discontinuity. (c) Acetabular reconstruction in second stage using ultraporous cup and augments

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sis, patient-specific instrumentation for intraoperative placement and guidance of screws as well as the custom fit, requiring little by way of intraoperative adjustment. Reported rates of aseptic loosening vary significantly, ranging from 0 to 11%, whilst dislocation remains the predominant reason for re-revision (0–30%) [16]. The cost of these custom implants is thought to be similar to those involved with the cup-cage technique using trabecular implants [17].

58.5 Components and Manufacturing Our experience of using custom components started when we noticed that conventional techniques and techniques such as the one described above using acetabular plate fixation was unable to cope with certain extensive bone defects and pelvic discontinuity. We have used two main Fig. 58.2  Image of a custom acetabulum component component designs and have published our with three flanges (Source—in-house planning image) results [18]. The first type of design was the Biomet the ilium onto the ischium and pubis (much like Patient-Matched Implants triflange acetabular a plate or reconstruction cage, but stronger), and components (Biomet Inc., Warsaw, IN, USA). which also functions as the acetabular compo- These components are milled from solid titanium nent of an arthroplasty. The surface coating has alloy and subsequently porous plasma spray and ongrowth potential and superior screw fixation hydroxyapatite-coated. The other design we have used was the versatility, which can ensure durable fixation for Materialise Patient-Specific Hip Implants longer. Moving forward, modern technology has pro- (Materialise NV, Leuven, Belgium) prosthesis. vided surgeons with the ability to combine the These implants are manufactured using additive above concepts of the cup-cage technique and 3D manufacturing (AM) technology with selective printing, to design and produce patient-specific laser melting that uses a focused laser beam to custom implants from high-resolution, computed melt titanium alloy (Ti6Al4V) powder layer-by-­ tomography (CT) scans. The resultant prosthesis layer. The implant is designed to have a highly has a cup with three integral flanges that screw to porous titanium inner surface in contact with the the ilium, ischium and pubis for instant, mechan- host bone to facilitate ongrowth. The inner ical stability whilst the ultra-porous or hydroxy- patient-specific instruments manufactured using apatite (HA) backing allows for reliable medical grade epoxy monomer were produced using the same AM technology. This offers biological osseointegration (Fig. 58.2). The benefits of such prostheses are the pre-­ 3D-printed drill guides that allow placing the operative planning software, allowing the design required cross-fixated screws as indicated by the of screw placement based on bone-stock analy- detailed preoperative plan.

58  Custom Prostheses for Acetabular Reconstruction in Revision Hip Arthroplasty

58.6 Preoperative Work Up and Planning Our preference is to perform a detailed and thorough clinical and radiological assessment. We routinely perform blood markers and synovial fluid aspirations to rule out periprosthetic joint infection. Detailed radiographic examinations include AP and Judet views of the pelvis, followed by computed tomography (CT) using spea

e

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cific protocols provided by the manufacturer. The defects were classified according to Paprosky and American Academy of Orthopaedic Surgeons (AAOS) classification systems and confirmed intraoperatively [16, 17]. We obtain a good quality thin cut (1 mm) CT scan of the pelvis, which is securely transferred to the manufacturers electronically. After this, a three-dimensional re-construction of the images is created (Fig.  58.3a–i). From this, a computer-­ c

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Fig. 58.3 (a, b) 3D reconstruction of the acetabulum, image showing bone loss. (c, d) Design of the prosthesis. (e) Heat map showing bone stock. (f, g) Planning of screw position. (h) Final plan with screw length. (i) Prosthesis implanted

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58.7 Surgical Technique

Fig. 58.4  3D Printed model

generated model of the bone stock was created and a prosthesis was designed. The electronic plan is available in a 3D format that allows manipulation of the images and a careful correlation of the screw position with the remnant bone stock in the pelvis. At this stage, the shape, size and orientation of the flanges can be modified and screw placement can be checked using subtraction techniques. As experience was gained, we have learned to incorporate screw positions using acetabular trauma experience such as the long anterior column screw inserted from inside the custom cup into the pubis and long posterior screws into the thick part of the sciatic buttress directed towards the sacroiliac joint (Fig. 58.3h). If required, a 3D printed model (Fig. 58.4) can be produced to check and fine-tune the design before the final prescription is created to manufacture the actual prosthesis.

Surgery is performed through an extensile posterior approach (Kocher Langenbeck) in the lateral position. The sciatic nerve is meticulously protected. The acetabulum is exposed, and dissection extended superiority into the ilium; anteriorly to the pubic bone and posteriorly exposing the ischium. Failed components are carefully removed to avoid significant bone loss and bony surfaces are prepared as per preoperative planning for the custom component positioning and screw placement. Sclerotic bony surfaces are curetted and minimally reamed or burred minimising host bone loss. Bone grafting using allograft can be added to fill in any small voids between the implant and host bone particularly medially to reconstruct medial defects and to bridge pelvic discontinuity defects. A sterile “model” of the actual component is also available for intra-operative trialling and fine-tuning the fit of the prosthesis to the host bone as well as confirming screw positions, hip centre of rotation, acetabular version and inclination. Screw placement guides are also provided to ensure accurate placement of the screws as per the plan. Once the final preparation is done, the real component is implanted as per the preoperative plan and stably fixed using the predetermined screw options (Fig. 58.5). The acetabular liner can be designed as a modular polyethylene liner that can be impacted into the triflange or a cemented liner that offers greater control on the version and inclination. Our preference now is to use a cemented dual mobility type of liner to provide protection against instability. Postoperatively, patients are mobilised weight bearing as tolerated. All receive routine antibiotic and thromboembolic prophylaxis. We prefer to follow-up with our patients for the long term.

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their series of 59 revision hips. They reported six reoperations for recurrent dislocations, but no removal of the triflange component was required. Gladnick [20] reported a 20.5% rate of triflange components where revision was indicated at a minimum 5-year follow-up, the main reasons being infection and instability. A systematic review in 2019 summarised the data from 17 articles. They reported an overall complication rate of 29%. Dislocation and infection were the commonest complications observed with an incidence of 11% and 6.2%, respectively. They also reported a 3.8% incidence of nerve injuries. The incidence of aseptic loosening was 1.7%. The overall survivorship was 82.7% at a mean follow-up was 57.4  months (range 10–215 months) [22]. Fig. 58.5  Intra-operative photograph of the seated component before screw insertion

58.8 Complications Majority of the series in the literature have small numbers [19–23] and short- to medium-term follow-­up. Most of the data come from a few centres that perform this type of surgery. Most studies have reported overall similar outcomes but with high rates of complications and component failures. This is a complex and technically ­ demanding surgery. Majority of the patients have had multiple previous revisions. The main complications are failure of the custom component, hip instability and infection amongst others. Attention must be paid to the important neurovascular structures in close proximity. A significant complication rate is reported in the published series in the literature. Taunton has reported on 57 revision hips. This series had a 35% complication rate. There were three failures of triflange components. Christie et  al. reported

58.9 Clinical Results We have published our clinical results in 17 hips treated with custom acetabular components between 2013 and 2017 [18]. The average follow-­up was 3.6  years (2–7  years). All patients had multiple previous surgeries. Bony defects were classified as Paprosky 3B in 13/17 hips (76%) with pelvic discontinuity encountered in the majority of cases 15/17 hips (88%) and intra-­ pelvic failed components in 11/17 (64%). At final follow-up, no radiographic failures were observed although three patients developed complications (17.6%); one patient had post-operative haematoma requiring washout; one patient had intra-operative ilium fracture; however, the implant was stable and no implant migration or failure was noted but remains under close monitoring. One patient who had recurrent dislocation underwent revision with a change of modular liner to a constrained liner and higher offset stem. No custom component has been revised yet (Fig. 58.6).

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a

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Fig. 58.6 (a, b) Pelvic discontinuity, extensive bone loss and partial intrapelvic protrusion after metal-on-metal failure with extensive pseudotumour. Reconstruction using custom triflange

58.10 Summary Our preference is to use a custom-designed acetabular prosthesis in cases where there are extensive defects with unsupportive and deficient acetabular columns, which do not allow stable fixation of standard implants even when the discontinuity can be fixed using column fixation techniques. This strategy allows these big defects to be bridged by the flanges of the custom component, which gain screw fixation in the ilium, ischium and pubic bone. The triangular fixation to the remaining host bone provides stability to the component and allows a revision arthroplasty to be implanted. Another advantage is that the

implant surface flanges allow biological ongrowth on host bone for long-term stability. These custom triflange components have improved conformity with host bone due to a meticulous and detailed planning process. The manufacturing technology also allows greater construct rigidity and resistance to fatigue failure, unlike thinner and more flimsy cages. The surgery, however, is technically demanding and is better performed as part of a revision hip service with a team of surgeons, anaesthetists, radiologists, vascular surgeons and microbiologists. There is the requirement for advanced imaging, lag time for the planning and manufacturing, expense of the implant and the inability to modify the implant intraoperatively.

58  Custom Prostheses for Acetabular Reconstruction in Revision Hip Arthroplasty

The short- to medium-term results remain satisfactory, but like all new technology, a robust follow-up protocol and long-term analysis of these cases is important.

References 1. Perona PG, Lawrence J, Paprosky WG, Patwardhan AG, Sartori M. Acetabular micromotion as a measure of initial implant stability in primary hip arthroplasty. J Arthroplast. 1992;7(4):537–47. 2. Afshar A, Steensma DP, Kyle RA.  Emile letournel: Pioneer of acetabular surgery. Mayo Clin Proc. 2021;96(5):1379–80. https://doi.org/10.1016/j. mayocp.2021.03.031. 3. Letournel E, Judet R.  Fractures of the acetabulum. 2nd ed. Berlin: Springer Verlag; 1993. 4. Chitre A, Wynn Jones H, Shah N, Clayson A.  Complications of total hip arthroplasty: periprosthetic fractures of the acetabulum. Curr Rev Musculoskelet Med. 2013;6(4):357–63. https://doi. org/10.1007/s12178-­013-­9188-­5. 5. Shah N, Wynn-Jones H, Clayson A.  Early total hip replacement after fractures of the acetabulum. In: Chapter 31 Mastering orthopedic technique. Total hip arthroplasty. Jaypee Brothers Medical Publishers; 2012. New Delhi, India. ISBN 978-81-8448-898-2. 6. Shah N, Wynn-Jones H, Clayson A. Management of periprosthetic fracture of the acetabulum. In: Chapter 38 Mastering orthopedic techniques. Total hip arthroplasty. Jaypee Brothers Medical Publishers; 2012. New Delhi, India. ISBN 978-81-8448-898-2. 7. Shah N, Wynn Jones H, Clayson A, Chitre A.  Management of pelvic discontinuity- two stage technique. In: Chapter 36: Mastering orthopedic technique. Revision hip arthroplasty. Jaypee Brothers Medical Publishers; 2017. New Delhi, India. ISBN 978-93-5152-486-1. 8. Paprosky WG, Perona PG, Lawrence JM. Acetabular defect classification and surgical reconstruction in revision arthroplasty. J Arthroplast. 1994;9(1):33–44. 9. Dearborn J, Harris W. High placement of an acetabular component inserted without cement in a revision total hip arthroplasty. Results after a mean of ten years. J Bone Jt Surg. 1999;88(4):469–80. 10. Whaley AL, Berry DJ, Harmsen WS.  Extra-large uncemented hemispherical acetabular components for revision total hip arthroplasty. J Bone Jt Surg. 2001;83(9):1352–7. 11. Youssef B, Wynn-Jones H, Clayson A, Shah N. Management of acetabular bone defects in revision hip arthroplasty. In: Chapter 28 Mastering orthopedic

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technique. Revision hip arthroplasty. Jaypee Brothers Medical Publishers; 2017. ISBN 978-93-5152-486-1. 12. Gross AE, Goodman S. The current role of structural grafts and cages in revision arthroplasty of the hip. Clin Orthop. 2004;429:193–200. 13. Garbuz D, Morsi E, Gross AE.  Revision of the acetabular component of a total hip arthroplasty with a massive structural allograft. Study with a minimum five-year follow-up. J Bone Joint Surg Am. 1996;78(5):693–7. 14. Saleh KJ, Jaroszynski G, Woodgate I, Saleh L, Gross AE.  Revision total hip arthroplasty with the use of structural acetabular allograft and reconstruction ring. J Arthroplast. 2000;15(8):951–8. 15. Hipfl C, Janz V, Löchel J, Perka C, Wassilew GI. Cup-­ cage reconstruction for severe acetabular bone loss and pelvic discontinuity: mid-term results of a consecutive series of 35 cases. Bone Jt J. 2018;100-B(11):1442–8. 16. Goodman GP, Engh CA Jr. The custom triflange cup: build it and they will come. Bone Jt J. 2016;98-B(1_Suppl._A):68–72. 17. Taunton MJ, Fehring TK, Edwards P, Bernasek T, Holt GE, Christie MJ.  Pelvic discontinuity treated with custom triflange component: a reliable option. Clin Orthop. 2012;470(2):428–34. 18. Matar HE, Selvaratnam V, Shah N, Wynn JH. Custom triflange revision acetabular components for significant bone defects and pelvic discontinuity: Early UK experience. J Orthop. 2020;21:25–30. https://doi. org/10.1016/j.jor.2020.01.053. 19. Taunton MJ, Fehring TK, Edwards P, Bernasek T, Holt GE, Christie MJ.  Pelvic discontinuity treated with custom triflange component: a reliable option. Clin Orthop Relat Res. 2012;470(2):428–34. 20. Gladnick BP, Fehring KA, Odum SM, Christie MJ, DeBoer DK, Fehring TK.  Midterm survivorship after revision total hip arthroplasty with a custom triflange acetabular component. J Arthroplast. 2018;33(2):500–4. 21. Wind MA Jr, Swank ML, Sorger JI.  Short-term results of a custom triflange acetabular component for massive acetabular bone loss in revision THA. Orthopedics. 2013;36(3):e260–5. 22. De Martino I, Strigelli V, Cacciola G, Gu A, Bostrom MP, Sculco PK.  Survivorship and clinical outcomes of custom triflange acetabular components in revision total hip arthroplasty: a systematic review. J Arthroplast. 2019;34(10):2511–8. https://doi. org/10.1016/j.arth.2019.05.032. Epub 2019 May 29 23. David Moore K, McClenny MD, Wills BW. Custom triflange acetabular components for large acetabular defects: minimum 10-year follow-up. Orthopedics. 2018;41(3):e316–20. https://doi. org/10.3928/01477447-­20180213-­11. Epub 2018 Feb 19

Megaprosthesis Reconstruction as a Salvage Option for Revision THR

59

Wolfgang Klauser and Jörg Löwe

59.1 Introduction It has been shown that the rate of revision hip surgery has significantly increased in the past years, especially in patients between 45 and 64 years of age, where the rate has gone up by more than 30% between 2007 and 2013. Reasons for implant revision are multiple including infection, aseptic loosening, recurrent dislocation or subluxation, persistent pain, implant and periprosthetic fractures as well as head/socket mismatch. With the increase of first revisions, the amount of revisions is also on the rise. The New Zealand Joint Registry [1] demonstrates that not only reasons for re-revision change, putting infection and dislocation on number one and two for reasons for re-revision, but also intervals in between revisions and re-revisions tend to get shorter. The National Joint Registry also observes that the risk for revision and re-revision tends to be highest if the primary hip replacement is revised within the first year of its implantation [2]. With revisions and re-revisions increasing, the surgeon becomes the dominant factor for the outcome of the revision surgery and for the future of the revision implant. The amount of bone loss at the time of revision certainly plays a significant W. Klauser (*) VAMED Ostseeklinik Damp, Damp, Germany J. Löwe Lubinus Clinicum, Kiel, Germany e-mail: [email protected]

role at this stage, often setting limits to the successful fixation of the revision implant. Bone loss might also arise when implants and adjacent structures such as bone and soft tissues are penetrated by the infection and need to be sacrificed to treat infection successfully. Several options exist to treat bone loss at the time of hip revision surgery. Rebuilding the bone stock using either bone graft and impaction grafting or bone substitute, composite allograft in combination with a revision implant have shown to provide good and durable outcomes if used correctly. An alternative to bone graft is the use of megaprosthesis to treat deficient bone stock and thus replace it with metallic components. This chapter describes the use of megaprosthesis in revision hip surgery and gives an overview of the literature. Megaprosthesis in hip surgery traditionally has been used in oncologic patients, e.g., in metastatic disease of the femur or primary bone tumors. Indications for these constructs have been expanded by surgeons to non-oncologic conditions such as septic and aseptic conditions. Although the technology of these implants has significantly advanced over the past decades, rates of complications still remain a major challenge and have been reported to go up to 50% with soft tissue failure, aseptic loosening, structural failure, and infection being the predominant causes for revision [3]. These complication rates, however, should be related to the outcome of alternative procedures and their original indica-

© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_59

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tion frequently being considered as limb-saving procedures. Surgeons who intend to use these constructs nonetheless should counsel the patient about the type and rate of complications that might arise.

59.2 Indications Indications for the use of megaprosthesis in hip revision surgery at our institution include major bone loss of the femur, e.g., in implant loosening or periprosthetic fracture, cases of periprosthetic infections where the bony structures need to be resected to prevent infection recurrence. It might also include various surgical indications, e.g., when femoral restoration using bone graft might be time-consuming and more challenging to an already impaired patient`s health than he or she

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can afford and a shorter surgical procedure is required. An alternative indication for using a megaprosthesis might be a situation where a cementless revision implant is well integrated yet difficult to remove and would cause major destruction to the bony integrity of the proximal femur upon removal. Frequently, resecting diseased necrotic bone is less time-consuming than reconstructing it in the elderly and multiple diseased patients and therefore is the preferred choice of treatment in these settings. The amount of bone loss to be considered sufficient for the use of a megaprosthesis, however, remains unclear and is not sufficiently discussed in the literature. In our experience, type V femoral bone loss as well as selected cases of type VI bone loss are routinely present when megaprosthesis is suggested for treatment at our hospital [4] (Fig. 59.1).

Fig. 59.1  Case of aseptic loosening of a total hip replacement 26 years after implantation with gross osteolysis around the femoral component in a 76-year-old patient

59  Megaprosthesis Reconstruction as a Salvage Option for Revision THR

59.3 Preoperative Planning Preoperative planning should include adequate counseling of the patient, evaluation of the patient’s history and a thorough clinical examination. Patients in need of a megaprosthesis will often have had multiple surgeries in the past and every effort should be undertaken to retrieve previous information about the patient’s history. Additional diagnostics should include aspiration of the hip joint to rule out infection. Preoperative radiographs must allow complete visualization of the implant as well as adjacent bone. CT scans before surgery will help to establish the amount of osseous destruction on either the acetabulum or the femur. In selected cases, angiography might prove helpful to visualize vascular compromises that require specific considerations. Fixation of a stemmed megaprosthesis requires sufficient fixation in the medullary canal of the femur to provide adequate stability and longevity. This should also include clinical examination of the knee located on the same side. Some patients present with osteoarthritic changes in their knee and preoperative planning should include optional operative therapy of the knee by either total knee replacement or osteotomy at a later stage. In some cases, conversion to a total femoral replacement at the same stage might be an option for the patient and should be discussed. Surgeons should take a rough estimate of the radiographs and decide on the distance for fixation into the medullary canal of the femur. In cases of remaining poor bone stock distally, a prophylactic cerclage wiring is recommended to prevent cracks upon insertion of the stemmed implant. The greater trochanter often can be detached with the gluteus medius left attached to it. It later can be fixed to the proximal femoral replacement to improve pelvic stability during gait, although successful and enduring reattachment is not always guaranteed. However, scar tissue will frequently develop around this construct and allow for stabilization of the pelvis. Surgeons should realize preoperatively if additional help might be required at the time of

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exposure and removal of the proximal femur. In cases of infections with severe periarticular ossifications around the acetabulum, a vascular surgeon might be recommended to help when exposing and debriding the femoral vascular structures. A neurosurgeon might provide additional help when exposing the sciatic nerve entrapped in ossifications or infected tissue. Preoperative planning should also include discussions with the anesthetist. The extent of the surgical procedure time should be highlighted and possible complications should be mentioned. In infected cases, the amount of blood loss frequently will be severe when debriding the infected soft tissues and therefore requires s­ pecial attention by the anesthesia staff. Once the soft tissues are cleaned, blood loss often tends to drop significantly.

59.4 Surgical Technique of Megaprosthesis Removal of remaining poor bone stock and bony debris allows for excellent access to the surgical field, facilitating acetabular reconstruction if needed. We routinely use the posterior approach in these cases and therefore place the patient in the lateral decubitus position (Fig.  59.2). The acetabulum should be stabilized using anterior and posterior padded support. This approach offers a lot of advantages: great exposure and easy extension options if needed. Important anatomical structures can be visualized and bony landmarks established. The downsides of this approach include difficulties when establishing the correct leg length and also a higher postoperative dislocation risk. Frequently, the soft tissue sleeve around the proximal femur needs to be detached from the bone for better visualization. The vastus lateralis muscle can be elevated out of its bed and mobilized anteriorly using Hohmann retractors to expose the femur shaft. Greater perforator veins should be identified and cauterized. The level of bone resection should be identified according to preoperative radiographs and the preoperative planning (Figs.  59.3, 59.4, and 59.5).

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Fig. 59.4  The detachment of the soft tissues from the femur with extended skin incision distally in a case with an infected total hip replacement (THR), post periprosthetic fracture, and failed osteosynthesis (see Fig. 59.7)

Fig. 59.2  Positioning of the patient in the lateral decubitus position should allow for sufficient room to extend skin incisions proximally and distally Fig. 59.5  Excellent exposure of the acetabulum and the tibia after the removal of infected THR and hinged knee implant. Multiple ligatures are visible in places where bleeding occurred. In cases like this, special care should be taken to conserve the extensor mechanism. The knee arthroplasty was exposed using a lateral approach, patella bone still visible near the clamps

Fig. 59.3  Exposure of a total hip replacement through posterior approach: significant preoperative bone loss with exposure of the femoral component, granuloma formation, and destruction of the gluteus medius muscle as frequently encountered in these cases. The posterior approach allows for easy expandability of the skin incision and the soft tissue mobilization

Upon closure, the soft tissues should completely cover the megaprosthesis and be partly re-attached to the implant, if possible. It was mentioned before that conserving the greater trochanter for reattachment might help to establish the correct leg length.

Full-length incision is mostly required for complete femoral replacement. However, since most of the modern systems are modular, two skin incisions might be an optional approach (Fig.  59.6). Two different incisions, one for the proximal femur as well as the hip socket and another for the knee joint are used. In non-­ infected or infected cases of total femoral replacement, the trial, as well as the original implant, are inserted from proximal to distal via a push through window through either the soft tissue sleeve or the remnant bone. It is our experience that this technique is not always easy yet facilitates the early mobilization of the patient.

59  Megaprosthesis Reconstruction as a Salvage Option for Revision THR

Fig. 59.6  Two incision techniques exposing proximal femur and acetabulum as well as knee joint via separate skin incisions can facilitate wound healing and faster mobilization of the patient

Modern implant systems will allow for cemented and cementless stem fixation depending on the thickness of the cortex and the age of the patient. Both options should be available at the time of surgery. Cementless fixation will require an intact isthmus of the shaft and a sufficient length of bone-implant engagement to allow for durable osteointegration of the stem. Ribbed, splined or fluted stems will provide sufficient rotational stability until osteointegration has occurred. In case of cemented stems, proper cementing techniques should be utilized using pre-cooled cement and a cement plug to pressurize the bone cement upon insertion. Technical problems might occur when sealing the medullary canal with a cement plug since the normal anatomy of the femur does not always allow for stable engagement of the seal. Bone cement might push the plug distally or pass the plug thus not allowing for optimum pressurization of the cement and good interdigitation of the cement into the cancellous bone. Great care should be taken to achieve stable engagement of the cement plug to allow for optimal cementing technique. Assessment of the size of the proximal femoral or even total femur replacement can be assessed by placing the amounts of resected bone and implant next to each other. This will give the surgeon a rough idea about the overall length of the distance to be replaced and confirm the measured distance on the preoperative radiographs. Trial components can be assembled on the back table and inserted manually. Leg length can be estimated using anatomical landmarks such as a

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greater trochanter fragment if present as well as soft tissue tension. The hip should be taken through the whole range of motion to trial for stability of the hip. Failure to achieve sufficient stability might require increased antetorsion of the proximal segment of the femoral component or increased anteversion of the acetabular component. In cases where instability continues to be a problem, additional mechanical constructs such as dual mobility cup or constrained liners have been suggested [5–7]. In cases of deficient soft tissue guidance of the hip, we prefer to use synthetic meshes that are attached to the implant but also to the soft tissues. These constructs tend to produce significant postoperative scarring which facilitates mobilization of the patient and safety against dislocation [8]. Total femoral replacement requires clinical evaluation of the knee flexion and extension. Knees should flex to at least 90° to allow for a comfortable sitting position. Surgeons should be aware that most of the soft tissues tend to stretch once the patient is mobile and getting more comfortable with their implant. Hip offset should be restored near to normal but not over- or undercorrected to avoid overloading the hip abducting muscles which need to be reattached to the implant or prevent muscle weakness which will lead to an impaired gait. Patients should be counseled to allow for sufficient time postoperatively to rehabilitate using walking aids and partial weight bearing (Figs. 59.7, 59.8 and 59.9).

Fig. 59.7  Failed osteosynthesis after periprosthetic fracture and THR, post multiple revisions and infection. The distal femur was initially preserved and then later removed to facilitate the implantation of a total femoral replacement. Placing the removed bone and implant next to each other on the table will give a rough estimate on the length of bone to be replaced

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764 Fig. 59.8 (a, b) The provisional assembly of the trial to total femur after periprosthetic fracture of a distal femoral replacement (a) as well the trial implant and original implant besides each other (b)

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Fig 59.9 (a) Trialing for the stability of the hip joint might require modification of the rotational alignment of the proximal femoral neck segment or an increase of the soft tissue tension of the hip. (b) With a trial implant in situ (total femoral replacement) the knee should flex to at least 90°. Patellar tracking should be observed when trialing and tracked centrally to establish the correct rotational alignment of the femoral component distally. (c) Rotational alignment of a proximal femoral replacement: Modularity of the implant will allow for correction of

b

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rotation once the original implant is inserted and fixed, intercalated segments allow for adjustment of leg length. (d) Total femur replacement inserted with intercalated segments, rotating hinge knee distally. Rotational alignment can be assessed using the trial neck segment. (e) Same implant as in Fig.  59.9d, original implant in situ with greater trochanter and gluteus medius reattached and fixed with cable cerclages. Care should be taken not to overcorrect the offset of the hip to avoid avulsion of the bone

59  Megaprosthesis Reconstruction as a Salvage Option for Revision THR

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Fig 59.9 (continued)

59.5 Complications After Megaprosthesis Reconstruction Complications after extensile mechanical reconstruction are manyfold. It should be mentioned, however, that most of the complications reported date from studies conducted in tumor centers from different locations that traditionally implant the majority of these systems. Infection rates here date from 5 to 35% in a single series. Korim [9] reviewed 14 studies with 356 proximal femoral arthroplasties in non-oncologic situations and noted a re-operation rate in this series of 23.8% with dislocation (15.7%) and infection (7.6%) being the most frequent ones. Mortality rates in these studies ranged from 0 to 40% (!). Viste et al. in their series of 44 patients with proximal femoral replacement noted a complication rate of 27% including infection and dislocation [10]. De Martino reported a re-revision rate of 22% with a five-year survival rate of 95.1% in their series of 41 proximal femoral replacements infection, dislocation, periprosthetic fracture, and aseptic loosening [11]. Alvand et al 2018 reviewed the results of 69 massive endoprostheses of the hip and knee joint for treatment of periprosthetic infections and reported a greater success rate in hips with a 83% eradication rate [12]. These numbers represent the complexity of complications of megaprosthesis in hip revision surgery.

Several strategies to reduce the infection rate have surfaced over the past years. Fiore et al systematically reviewed publications on silver-­coated megaprosthesis to prevent and treat periprosthetic infections. They reported a decrease of the overall infection rate when silver-­coated implants were used [13]. Different types of silver coatings showed different rates of infection reduction with a low rate of side effects and the conclusions of this publication suggested that silver-coated megaprostheses were safe and effective to use in this subset of patients and indications. Some of those coatings were more reliable than others. Hardes et al. [14] reported a significant reduction of periprosthetic infections with silver-coated megaprosthesis (5.9%) in patients with bone sarcoma in a prospective 5-year study compared to standard titanium implants (17.6%) with a high rate of amputations in the titanium group (38.5%) [15]. Alternatives include coating of the prosthesis with bone cement that contains manually added antibiotics as we have routinely done in the past as well as antimicrobial coating with iodine. Some promising results were published using this technique in 2012 [16–18]. Modern implant systems nowadays offer a variety of fixation techniques as well as a broad selection of modularity that will allow the surgeon to react to difficult surgical conditions using various intercalating and modular neck segments. In case of a proximal femoral replacement, mod-

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ern implant systems will allow for stem extensions distally that allow connecting a knee arthroplasty to the system, thus containing the viable femoral bone in the middle. Cementless fixation in these systems is recommended in patients with good and viable bone stock and is available with or without hydroxyapatite coating or press-fit type with porous-­ coated collars and ribbed stems with a microporous sandblasted surface [19–22]. Alternative techniques include compressive osteointegration in combination with trabecular metal for proximal and distal femoral replacement [23, 24].Whereas the amount of femoral bone resection distally does seem to have a significant impact on the survival of a distal femoral replacement, there is to our knowledge no evidence that the amount of bone resection will severely reduce the survival of a proximal femoral replacement [11]. Care should be taken, however, to restrict the amount of bone resection to the least level possible.

59.6 Case Study Case 1  A 75-year-old female patient presented at our hospital with severe and increasing pain in her left hip. She had had hip replacement surgery in 1989 at a different hospital and the hip had been functioning well over the past decades. However for the last 2 years, the pain had increased and then the patient had developed a Fig. 59.10  X-ray hip overview and lateral view of a 75-year-old patient with bone resorption on the left proximal femur 30 years after primary implantation

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limping and antalgic gait. She complained not only of pain but also of muscle weakness and a limited walking distance of about 1 km. She had to use walking aids by now and her visual analogue scale (VAS) score had increased to 8/10. Major comorbidities included cardiac arrhythmia, diabetes mellitus type II, hypertension, and 2nd stage renal insufficiency. Clinical examination showed muscle insufficiency of the hip abductors with no capacity to elevate the left leg in a lateral position of the patient. Good range of motion for the left hip was found and no clinical signs of infection could be seen. The previous scar had healed uneventfully and showed good mobility. There was a severe amount of tenderness around the hip joint. Radiographs showed resorption of the proximal femur 30 years after primary implantation of the THR. A small bony fragment of the greater trochanter was still visible with a stretch of complete bone loss of the lateral cortex of the proximal femur of about 8 cm (Fig. 59.10). On preoperative radiographs, a small bone defect in the medial wall of the acetabulum was noticed as well. Revision hip surgery was suggested. Preoperative planning included aspiration of the hip joint with negative results. Lab parameters showed no elevation of leucocyte count and C-reactive protein (CRP). Preoperative planning included calculation of the bone defect on the proximal femur and replace-

59  Megaprosthesis Reconstruction as a Salvage Option for Revision THR

ment with a segmental component as well as a modular neck segment. It was also anticipated before surgery that the sharp edge of the primary femoral component to be removed might have eroded the soft tissues and the gluteus medius muscle. The surgical plan also anticipated a soft tissue deficiency at the time of surgery mainly due to the sharp edge of the femoral primary component to be removed (Figs. 59.11, 59.12, 59.13, 59.14, 59.15, 59.16, 59.17, 59.18, 59.19 and 59.20).

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femur magaprosthesis. Unfortunately, the patient had a fall and sustained a fracture of the prosthesis stem within months after the first revision (Fig. 59.22a–c). This patient was revised to a total femoral replacement prosthesis (Fig. 59.23a, b).

Case 2  A 50-year-old patient who had undergone a distal femur replacement 4 years ago presents with aseptic loosening of the prosthesis (Fig.  59.21a–c). It was revised to another distal Fig. 59.12  Patient in lateral position. A marking pen was used to outline the intended skin incision with incorporating the distal part of the old scar

Fig. 59.13  Exposure of the femoral component: confirmation of severe soft tissue erosion due to the femoral components’ sharp edge with complete loss of greater trochanter, fatty degeneration of the gluteus medius muscle

Fig. 59.11  Long AP radiographs of the left hip showing the preoperative situation and the preoperative planning. A press-fit cup was intended to be used on the acetabular side along with bone graft to stabilize the medial wall in case of a contained defect. A proximal femoral replacement on the femoral side was planned with cemented stem extension due to poor bone quality of the femur which was expected during surgery

Fig. 59.14  Stepwise exposure of the proximal femur, showing amount of proximal bone loss and poor quality of the bone. The femoral component proved to be loosened yet still fixed to the poor bone

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Fig. 59.15  After removal of component, fatigue fracture of the proximal femur occurred, confirming very thin walls of the bone

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Fig. 59.16  The acetabular component was revised as well with signs of loosening. Only fibrous tissue adhering to the socket as shown in this picture with significant damage to the anterior and medial wall of the acetabulum due to osteolysis and resorption of the bone

b

Fig. 59.17 (a, b) Remaining femoral bone has been stripped from the soft tissues and a cable protects the bone from further fracturing distally. A flexible reamer is used

to cleanse the femoral canal from remaining debris and membranes

59  Megaprosthesis Reconstruction as a Salvage Option for Revision THR

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Fig. 59.18 (a, b) Remaining bone resected to create even surface for the segment of the proximal femoral component. A milling device can be used to create a flush surface of the bone. The resected bone is used to calculate the

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approximate distance for adequate restoration of the bone with the megaprosthesis. Once, the bone has been resected reconstruction of the acetabulum is performed using the great exposure which is now available

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Fig. 59.19 (a–c) After reconstruction of the acetabulum and implantation of the acetabular component, trialing with the megaprosthesis using different segment lengths is performed, to establish correct offset and soft tissue tension of the hip. Stability of the hip can be assessed by

modifying antetorsion of the neck segment. (b) The original implant which is then cemented in place (c) with the fixed neck segment antetorsion, establishing the correct trial head length

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770 Fig. 59.20  The radiograph result after revision: Impaction graft technique had been used as well as a reconstruction cage to stabilize the acetabular situation. A bone block had been placed to block the medial wall, which later migrated centrally due to the impaction of the bone. The femoral canal had been sealed using resorbable sponges to prevent the cement from penetrating deeper into the canal. A mesh was used to improve the stability of the soft tissues and the hip joint which was fixed distally using a second cerclage around the remaining femoral shaft

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Fig. 59.21 (a, b) Full-length radiographs of lower limb showing the loosened distal femur megaprosthesis. (c, d) Radiographs of the knee AP & lateral views showing the radiolucency at the cement bone interface

59  Megaprosthesis Reconstruction as a Salvage Option for Revision THR Fig. 59.22 (a, b) Revision of the distal femur to a longer prosthesis. (c) Stem failure at the junction of prosthesis

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Fig. 59.23 (a, b) Revision is done using a total femur replacement prosthesis. The abductors along with the trochanter and proximal femur are attached to the prosthesis using cerclage cables. The tibial component has not been revised

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59.7 Discussion Results of megaprosthesis that have been reported vary and certainly contain a large number of different patient inclusion criteria, surgical techniques and various indications for its use. This has a significant effect on the outcome of these implants and this should be kept in mind when going through the literature and looking at the results. Case series are small and follow-up of these patients in general is short. We therefore only report on a limited number of publications. Viste et al. in 2017 reported a survival rate free of any revision or removal of an implant of 86% at 5 years and 66% at 10 years [10]. De Martino reported a 5-year survival rate of 95.1% in 40 patients for aseptic loosening [11]. Toepfer et al. in 2016 reported on the outcome of 18 total femoral replacements that had been inserted for treatment of periprosthetic fractures and cases of aseptic loosening and massive bone loss where other alternative treatment options did not seem suitable. They reported a revision rate of 72% in their series with exchange of total femur replacement in 22% of their cases. Soft tissue problems and infection as well as mechanical failure were the most predominant reasons for revision surgery [25]. Twenty-two total femoral replacements were also evaluated by Graulich et  al. Indications for implantation in their series included tumors, infections, and fractures with a mean follow-up of 18 months. At the time of final follow up, 15 of their patients had survived with preserved limbs. In their series, five patients underwent secondary hip exarticulation and 11 patients suffered from infection, of which five patients died [26].

59.8 Summary Megaprosthesis around the proximal femur including total femoral replacements frequently are reported as salvage procedures with limited functional outcome. Indeed, the rate of intra- and perioperative complications ranges from 20 to 72% and patients should be informed about the extent of the procedure. They should also be

informed that this procedure is considered as a salvage procedure trying to keep the patient mobile. Gait impairment might be one of the consequences of this surgery. It is our belief that these cases should be treated in orthopedic specialty centers that perform these surgeries on a regular basis and have enough experience to treat the possible complications. Patients should be treated by an expert team including members from the departments of anesthesia and internal medicine for preoperative evaluation of the patient, a surgeon with adequate experience in treating these cases, and a vascular or neurosurgeon if need may be and preoperative diagnostics hint in this direction. Physiotherapists and nursing staff should be involved early to monitor the postoperative treatment of the patient and the rehabilitation.

References 1. McKie J, Brendan C, Devane P, Frampton C, Muir D, Young S, Graydon A., Griffin H, Kearney P, Pettett A. NZOA Joint Registry | New Zealand Orthopaedic Association. NZOA Joint Registry. 2020. https://nzoa. org.nz/nzoa-­joint-­registry. 2. Ben-Shlomo Y, Blom A, Boulton C, Brittain R, Clark E, Craig R, Dawson-Bowling S, Deere K, Esler C, Espinoza O, Goldberg A, Gregson C, Howard P, Hunt L, Jameson S, Jennison T, Judge A.  The National Joint Registry 17th Annual Report 2020 [Internet]— PubMed. The National Joint Registry. 2020. https:// pubmed.ncbi.nlm.nih.gov/33439585/. 3. Henderson ER, Groundland JS, Pala E, Dennis JA, Wooten R, Cheong D, Windhager R, Kotz RI, Mercuri M, Funovics PT, Hornicek FJ, Temple HT, Ruggieri P, Letson GD.  Failure mode classification for tumor endoprostheses: retrospective review of five institutions and a literature review. In J Bone J Surg Ser A. 2011;93(5):418–29. https://doi.org/10.2106/ JBJS.J.00834. 4. Paprosky WG, Aribindi R.  Hip replacement: treatment of femoral bone loss using distal bypass fixation. Instr Course Lect. 2000;49:119–30. https://pubmed. ncbi.nlm.nih.gov/10829168/ 5. Ozden VE, Dikmen G, Beksac B, Tozun R.  Dual-­ mobility bearings for patients with abductor-­trochanteric complex insufficiency. HIP Int. 2018;28(5):491–7. https://doi.org/10.1177/1120700018757788. 6. Smith EL, Shah A, Son SJ, Niu R, Talmo CT, Abdeen A, Ali M, Pinski J, Gordon M, Lozano-Calderon S, Bedair HS.  Survivorship of megaprostheses in revision hip and knee arthroplasty for septic and asep-

59  Megaprosthesis Reconstruction as a Salvage Option for Revision THR tic indications: a retrospective, multicenter study with minimum 2-year follow-up. Arthroplasty Today. 2020;6(3):475–9. https://doi.org/10.1016/j. artd.2020.05.004. 7. Vaishya R, Vijay V, Vaish A.  Successful salvage of an unstable Girdlestone’s excision arthroplasty with a megaprosthesis of the hip. J Clin Orthop Trauma. 2015;6(4):269–72. https://doi.org/10.1016/j. jcot.2015.03.005. 8. Elbuluk AM, Coxe FR, Schimizzi GV, Ranawat AS, Bostrom MP, Sierra RJ, Sculco PK.  Abductor deficiency-­induced recurrent instability after total hip arthroplasty. JBJS Rev. 2020;8(1):e0164. https://doi. org/10.2106/JBJS.RVW.18.00164. 9. Korim MT, Esler CNA, Ashford RU. Systematic review of proximal femoral arthroplasty for non-­neoplastic conditions. J Arthroplasty. 2014;29(11):2117–21. https://doi.org/10.1016/j.arth.2014.06.012. 10. Viste A, Perry KI, Taunton MJ, Hanssen AD, Abdel MP.  Proximal femoral replacement in contemporary revision total hip arthroplasty for severe femoral bone loss. Bone Jt J. 2017;99B(3):325–9. https://doi. org/10.1302/0301-­620X.99B3.BJJ-­2016-­0822.R1. 11. De Martino I, D’Apolito R, Nocon AA, Sculco TP, Sculco PK, Bostrom MP.  Proximal femoral replacement in non-oncologic patients undergoing revision total hip arthroplasty. Int Orthop. 2019;43(10):2227– 33. https://doi.org/10.1007/s00264-­018-­4220-­4. 12. Alvand A, Grammatopoulos G, de Vos F, Scarborough M, Kendrick B, Price A, Gundle R, Whitwell D, Jackson W, Taylor A, Gibbons CLMH.  Clinical outcome of massive endoprostheses used for managing periprosthetic joint infections of the hip and knee. J Arthroplasty. 2018;33(3):829–34. https://doi. org/10.1016/j.arth.2017.09.046. 13. Fiore M, Sambri A, Zucchini R, Giannini C, Donati DM, De Paolis M.  Silver-coated megaprosthesis in prevention and treatment of peri-prosthetic infections: a systematic review and meta-analysis about efficacy and toxicity in primary and revision surgery. Eur J Orthop Surgery Traumatol: Orthop Traumatol. 2021;31(2):201–20. https://doi.org/10.1007/ s00590-­020-­02779-­z. 14. Hardes J, Von Eiff C, Streitbuerger A, Balke M, Budny T, Henrichs MP, Hauschild G, Ahrens H. Reduction of periprosthetic infection with silver-coated megaprostheses in patients with bone sarcoma. J Surg Oncol. 2010;101(5):389–95. https://doi.org/10.1002/jso.21498. 15. Schmidt-Braekling T, Streitbuerger A, Gosheger G, Boettner F, Nottrott M, Ahrens H, Dieckmann R, Guder W, Andreou D, Hauschild G, Moellenbeck B, Waldstein W, Hardes J. Silver-coated megaprostheses: review of the literature. Eur J Orthop Surg Traumatol. 2017;27(4):483–9. https://doi.org/10.1007/s00590-­ 017-­1933-­9. Springer-Verlag France 16. Tsuchiya H, Shirai T, Nishida H, Murakami H, Kabata T, Yamamoto N, Watanabe K, Nakase J.  Innovative antimicrobial coating of titanium implants with

773

iodine. J Orthop Sci. 2012;17(5):595–604. https://doi. org/10.1007/s00776-­012-­0247-­3. 17. Lam YL, Yau R, Ho KWY, Ho PL. Antibiotic-laden cement wrap: A simple but effective way of treating patients with megaprosthesis infection. J Orthop Surg. 2019;27(1):2309499019825587. https://doi. org/10.1177/2309499019825587. 18. Shirai T, Tsuchiya H, Nishida H, Yamamoto N, Watanabe K, Nakase J, Terauchi R, Arai Y, Fujiwara H, Kubo T.  Antimicrobial megaprostheses supported with iodine. J Biomater Appl. 2014;29(4):617–23. https://doi. org/10.1177/0885328214539365. 19. Oliva MS, Vitiello R, Cauteruccio M, Pesare E, Rovere G, Meschini C, Liuzza F, Maccauro G, Ziranu A.  Cemented versus cementless megaprosthesis in proximal femur metastatic disease: a systematic review. Orthop Rev. 2020;12(1S):129–32. https://doi. org/10.4081/or.2020.8689. 20. Bruns J, Delling G, Gruber H, Lohmann CH, Habermann CR. Cementless fixation of megaprostheses using a conical fluted stem in the treatment of bone tumours. J Bone Jt Surg Ser B. 2007;89(8):1084–7. https://doi.org/10.1302/0301-­620X.89B8.19236. 21. Conrad EU, Lindberg AW, White JK, Ching RP. Uncemented megaprosthesis stem fixation using “Scratch Fit” to achieve improved implant ­fixation. Ann Joint. 2019;4:36. https://doi.org/10.21037/ aoj.2019.08.05. 22. Li Y, Sun Y, Shan HC, Niu XH. Comparative analysis of early follow-up of biologic fixation and cemented stem fixation for femoral tumor prosthesis. Orthop Surg. 2019;11(3):451–9. https://doi.org/10.1111/ os.12483. 23. Kramer MJ, Tanner BJ, Horvai AE, O’Donnell RJ.  Compressive osseointegration promotes viable bone at the endoprosthetic interface: retrieval study of Compress® implants. Int Orthop. 2008;32(5):567– 71. https://doi.org/10.1007/s00264-­007-­0392-­z. 24. Farfalli GL, Boland PJ, Morris CD, Athanasian EA, Healey JH.  Early equivalence of uncemented press-­ fit and compress® femoral fixation. Clin Orthop Rel Res. 2009;467(11):2792–9. https://doi.org/10.1007/ s11999-­009-­0912-­9. 25. Toepfer A, Harrasser N, Petzschner I, Pohlig F, Lenze U, Gerdesmeyer L, Pförringer D, Toepfer M, Beirer M, Crönlein M, Von Eisenhart-Rothe R, Mühlhofer H. Short- to long-term follow-up of total femoral replacement in non-oncologic patients. BMC Musculoskeletal Dis. 2016;17(1):1–9. https://doi. org/10.1186/s12891-­016-­1355-­6. 26. Graulich T, Steimer D, Zhang D, Omar M, Weber-­ Spickschen S, Krettek C, Panzica M. High complication and revision rates after total femoral replacement: a retrospective single center analysis of indication, function, and complication. Arch Orthop Trauma Surg. 2019;139(7):913–20. https://doi.org/10.1007/ s00402-­019-­03130-­w.

Conversion of Failed Hemiarthroplasty to Total Hip Arthroplasty Harish S. Bhende

60

and Prakash K. George

Abbreviations

60.1 Introduction

AMP AMR ASA

Intracapsular femoral neck fracture is one of the most common geriatric orthopedic emergencies. Hemiarthroplasty (Hemi) has been the standard of treatment for these patients right from the 1950s when Austin Moore published his results of self-locking metal hip prosthesis by posterior approach [1]. He was cautious about the post-­ operative rehabilitation in these elderly patients. He recommended gradually increasing weight bearing for over 6  months and the use of cane thereafter. The suggested slow rehabilitation was to allow time for bone in-growth into the fenestrations of the prosthetic stem. In his classic article, he stressed that the patient selection was very important for success of this prosthesis. According to Austin Moore, bone in-growth in the holes of prosthetic stem and strengthening of medullary bone due to progressive loading forces were essential factors for a successful outcome. He also mentioned that, when this did not happen, the prosthetic stem started sinking into the medullary cavity and the implant failed. He did not report a single dislocation or intraoperative fracture in his 153 cases operated by posterior approach. The observations he made almost 60 years ago were so accurate, that even today we realize their validity when we study the literature on the analysis of failed Hemiarthroplasties. Today, the use of Hemi as a primary mode of treatment for intracapsular neck femur fractures

Austin Moore Prosthesis Austin Moore Replacement American Society of Anaesthesiology ESR Erythrocyte Sedimentation Rate Hemi Hemiarthroplasty HRQOL Health-related quality of life MARS CT scan Metal Artefact Reduction Software Computed Tomography MRI Magnetic Resonance Imaging NICE National Institute for Health and Care Excellence Tc99 Technetium99 THA Total Hip Arthroplasty UK United Kingdom USD United States dollar USG Ultrasonography

H. S. Bhende (*) · P. K. George Center for Joint Replacement Surgery—Laud Clinic, Mumbai, Maharashtra, India

© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023 M. Sharma (ed.), Hip Arthroplasty, https://doi.org/10.1007/978-981-99-5517-6_60

775

776

is decreasing while total hip arthroplasty (THA) surgery has gained momentum. Khan et al. presented data from the UK Registry showing an increasing trend for primary THA following National Institute for Health and Care Excellence (NICE) guidelines, which showed better mobility, improved health-related outcome measures, and lower revision rates following THA compared to primary Hemi [2]. In two other review articles, Zhao et  al. and Alzijani et  al. summarized that THA is the preferred option due to its safety, efficacy, higher success rate, better functional and pain scores, improved rate of recovery, and lower complications [3, 4]. Although the rate of dislocation was shown to be higher than the hemiarthroplasty, THA was still preferred in more active patients. Bheeshma Ravi et  al. in their propensity score matched population-based study have shown that in the long run, the THA was 2700 USD cheaper to healthcare system compared to hemiarthroplasty due to reduced risk of reoperation [5]. Scandinavian countries, however, have different stories to tell. Hansson et al. reported that 81 percent of cases of intracapsular fracture neck femur in Sweden were treated with hemiarthroplasties, as per Swedish registry data between 2005 and 2011 [6]. When they compared outcomes between Hemi and THA for intracapsular fractures, they found higher hip-related complications in THA group. However, medical complications and one-year mortality were lesser with THA. Based on their study, they advised against doing primary THA for all intracapsular neck fractures. According to them, it should be reserved for younger and more active cohorts only. Moerman et al. from the Dutch arthroplasty registry have shown that 40% of neck femur fractures were treated with Hemi or THA (others are treated with internal fixation) [7]. They found a higher rate of revisions in THA patients compared to Hemi. Male gender, age less than 80  years, non-cemented fixation and posterior approach were the risk factors for failure.

H. S. Bhende and P. K. George

60.2 How Often Hemi Fails? One of the main reasons several surgeons are turning away from primary hemiarthroplasties for neck femur fractures is the plethora of complications seen following the surgery. Chaplin et  al. reviewed cases operated in a single large district general hospital in the UK over a five-­ year period [8]. They found that periprosthetic fracture, infection, stem loosening, unexplained pain, and dislocation were the main causes of failure. They quoted a 12% prevalence of complications, 8% prevalence of failure at 3-year follow-­ up, and 29% mortality at one-year post-surgery in their study. They mentioned that the actual complications may be higher as not all patients were followed up regularly in the UK due to their existing health policy. The data presented by Ekman et  al. from Finland shows a cummulative 12% rate of complications (5% dislocations, 2.8% infections, 2.8% periprosthetic fractures, 0.8% protrusio acetabuli), in cemented hemiarthroplasties done on patients with average age of 80 years [9]. They had reported a 79% rate of mortality at 9-year follow-up. Their patient group was quite elderly with multiple comorbidities. With such a low post-arthroplasty life expectancy, in this frail aging group with multiple comorbidities, they question the role of THA instead of hemiarthroplasty. Sarpong et  al. has reported prosthetic loosening as the main cause for revision (45%), whereas other less commonly reported causes included protrusio acetabuli (33%), periprosthetic fracture (11%), dislocation (8%), and limb length discrepancy in 2% [10]. The use of bipolar prosthesis in place of mono-­ block components was suggested by Hedbeck et al. in their randomized controlled trial [11]. In 120 patients with average age of 86  years who underwent either mono-block Hemi or bipolar Hemi for neck femur fracture, there was a four-­ fold increase in the rate of acetabular erosion with mono-block prosthesis. There was also an increased tendency for poorer functional scores

60  Conversion of Failed Hemiarthroplasty to Total Hip Arthroplasty

and worse health-related quality of life (HRQOL) score in the mono-block group. In a pooled analysis of 30,250 patients, Imam et  al. concluded that bipolar prosthesis gives a better range of movement, lesser acetabular erosions, and lesser reoperations, but has slightly longer operation time [12]. In their study, the pain relief and other complication rates were the same in both groups. From the analysis of the above studies, a pattern emerges that the Hemi works reasonably well in very elderly patients, who have limited physical activity and relatively short life expectancy. The complications are more common in younger age groups with higher activity levels and life expectancy longer than 10  years. This group should therefore be offered THA for improved functional outcomes and longer survival.

60.3 Mechanisms of Failure of Hemiarthroplasties The main symptom of Hemi failure is groin pain or thigh pain. Groin pain is attributed to acetabular erosion following Hemi (Fig.  60.1). Many

a

b

Fig. 60.1  Chondrolysis with Protrusio  – (a) Typical appearance of chondrolysis seen at revision surgery for painful Hemi. (b) Well-fixed hemi with bone growth seen in stem fenestration and reactive bone formation at the tip

777

reasons are postulated for cartilage wear and acetabular erosion following Hemi. Initial damage to the acetabular cartilage during trauma, metal articulating with biological human cartilage, foreign body in acetabulum, and osteoporosis are some of the possible mechanisms whereby patients develop acetabular erosion. However, not all patients with a radiological appearance of acetabular protrusion experience pain. When a patient has pain in the thigh, it is usually due to stem loosening. Non-cemented stems have a higher risk of loosening in osteoporotic bones of elderly patients. During primary hemiarthroplasty, the use of non-cemented stem occasionally causes a femoral fracture when the surgeon attempts to get a good primary implant fit in an osteoporotic bone. The stem size required in a wide canal osteoporotic femur is usually big. This large well-fitting femoral stem, in a thin-­ walled osteoporotic femur, leads to severe discrepancy in elastic indices of the bone bearing the stem and the bone distal to it. This leads to an increased risk of periprosthetic fractures in these patients. Thus, the revision rate was reported to be 1.77 times higher for noncemented hemiarthroplasties compared to

c

of the stem. (c) Protrusio acetabuli with loss of joint space and subchondral sclerosis seen in hemiarthroplasty after a few years in situ. Note the bone growth in stem fenestration. This mild protrusion is not always painful

H. S. Bhende and P. K. George

778

a

b

c

d

Fig. 60.2  Stem perforation—(a) 8  months following Hemi for neck femur fracture. Patient had thigh pain from the time of surgery. (b) Lateral view showing posterior

perforation, not an uncommon intraoperative complication. (c, d) Revision with hybrid THA and long cemented stem

cemented by Okike et  al. [13]. They studied 12,400 patients above the age of 60 who underwent hemiarthroplasty for neck femur fracture. At 1-year follow-up, 3% revisions were required for uncemented hemi compared to cemented Hemi 1.3% (p