Orthopedic Care of Patients with Cerebral Palsy: A Clinical Guide to Evaluation and Management across the Lifespan [1st ed.] 9783030465735, 9783030465742

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Orthopedic Care of Patients with Cerebral Palsy A Clinical Guide to Evaluation and Management across the Lifespan Philip D. Nowicki Editor

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Orthopedic Care of Patients with Cerebral Palsy

Philip D. Nowicki Editor

Orthopedic Care of Patients with Cerebral Palsy A Clinical Guide to Evaluation and Management across the Lifespan

Editor Philip D. Nowicki Department of Orthopedics Helen DeVos Children’s Hospital Grand Rapids, MI USA

ISBN 978-3-030-46573-5    ISBN 978-3-030-46574-2 (eBook) https://doi.org/10.1007/978-3-030-46574-2 © Springer Nature Switzerland AG 2020 This work is subject to copyright. All rights are reserved 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 Switzerland AG The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

Preface

Starting practice straight out of fellowship, I began my career as a practitioner of pure pediatric orthopedics. Over time and with a change in positions, I gradually developed a focus in my practice as many pediatric orthopedists do. One of my interests was in the care for children and young adults with cerebral palsy. These patients were the happiest people I met in my practice and they were also some of the most resilient. They demonstrated to me true persistence and joy, and it touched my heart as well as inspired me to personally persevere. Though I maintain other interests in pediatric orthopedics, I particularly enjoy the challenge and complexity of patients with cerebral palsy as they are individually unique, and caring for them is unlike anything else. Starting out, there was not any textbook that I could easily reference for quick and practical guidelines to care for my patients with cerebral palsy. I felt that this created a gaping hole in my personal practice. I therefore envisioned a book that I would have loved to have had when training in my fellowship and early practice years that would have offered common principles and procedures covering the entire magnitude of care for patients with cerebral palsy. This would have simplified my practice, and it is for this reason that the idea for this book came about. This book was conceived to be a guidebook for all orthopedic surgeons or medical practitioners interested in caring for patients with cerebral palsy. It is not meant to be an exhaustive text, but instead is focused on practical knowledge to utilize in the setting of a private office, multi-specialty clinic, or operating room. Numerous authors have taken great time and effort to provide their experience in managing patients with cerebral palsy, and all of the authors have practices that are focused on neuromuscular care. The choice to involve multiple physicians from both non-operative and operative backgrounds offers a more global approach to the care in these challenging but incredible patients. Even though many multispecialty clinics seem to be disappearing, the use of the electronic medical record and digital imaging allows sharing of patient information, care, and planning across the digital divide, allowing the “clinic without walls” to prosper and enable a more efficient way to care for patients. It is hoped that this book will allow clinicians to better care for their patients across the spectrum. Although focused on orthopedic care, it is hoped that this book will not be used by orthopedists alone. There are multiple chapters that focus on non-­ operative management, and what separates this book from others that are currently available is that the text explains patient care across the lifespan, v

Preface

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and includes information on bracing, spasticity management, orthopedic procedures for adult patients with cerebral palsy, and a special chapter focused on transition care and end of life issues. There is also a chapter that focuses on physical and occupational rehabilitation for patients with cerebral palsy, coming from the perspective of therapists rather than physicians. This is hoped to allow the surgeon to obtain care from a completely different perspective as therapy is where our patients truly become “better.” Finally, at the end of the text is an appendix that offers some resources for patients and caregivers as well as medical providers to assist their patients reach their highest potential. On behalf of my co-authors and myself, I hope that you enjoy reading through this text and that you will find it useful to yourself and your trainees along the way. We applaud you for your time and dedication to the care of patients with cerebral palsy, and we know you will find personal accomplishment and joy in doing so. Grand Rapids, MI, USA

Philip D. Nowicki

Contents

1 Introduction to the Cerebral Palsies����������������������������������������������   1 Henry G. Chambers and Reid C. Chambers 2 Principles of Orthotics and Other Durable Medical Equipment����������������������������������������������������������������������������������������  13 Lisa M. Voss 3 Spasticity Management: Nonoperative and Operative����������������  29 Heakyung Kim, Eduardo Del Rosario, Richard Anderson, Nicole Bainton, Jared Levin, and Angeline Bowman 4 Gait Evaluation for Patients with Cerebral Palsy������������������������  51 Hank White and Samuel Augsburger 5 Multilevel Orthopedic Surgery for Patients with Cerebral Palsy����������������������������������������������������  77 Kristan Pierz and M. Wade Shrader 6 Orthopedic Hip Surgery for Patients with Cerebral Palsy����������  93 Emily Dodwell, Kunal Agarwal, Stacey Miller, Kishore Mulpuri, Ernest Sink, Philip D. Nowicki, Venkat Boddapati, and Roshan P. Shah 7 Orthopedic Leg and Knee Surgery for Patients with Cerebral Palsy�������������������������������������������������������������������������� 145 David Westberry, Lane Wimberly, Cory Bryan, Adam Theissen, Venkat Boddapati, Roshan P. Shah, and Philip D. Nowicki 8 Orthopedic Foot and Ankle Surgery for Patients with Cerebral Palsy�������������������������������������������������������������������������� 171 Christine Goodbody, Liana Tedesco, J. Turner Vosseller, and David M. Scher 9 Orthopedic Spine Surgery for Patients with Cerebral Palsy ������ 193 Nickolas Nahm, M. Wade Shrader, Hiroko Matsumoto, and David Roye 10 Upper Extremity Surgery for Patients with Cerebral Palsy�������� 213 Lisa Maskill

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11 Principles of Rehabilitation: Occupational and Physical Therapy���������������������������������������������� 221 Amber Newell, Suzanne Cherry, and Michaela Fraser 12 Adaptive Activities for Patients with Cerebral Palsy�������������������� 251 Arianna Trionfo and Corinna Franklin 13 Transition and Lifespan Care for Patients with Cerebral Palsy�������������������������������������������������������������������������� 257 Rita Ayyangar, David Roye, Sara Silbert, and Christian Treat Appendix �������������������������������������������������������������������������������������������������� 287 Index���������������������������������������������������������������������������������������������������������� 291

Contents

Contributors

Kunal  Agarwal, MS University of Virginia School of Medicine, Charlottesville, VA, USA Richard  Anderson, MD Division of Pediatric Neurosurgery, Columbia University Irving Medical Center, New York, NY, USA Samuel  Augsburger, MSME  Motion Analysis Center, Shriners Hospitals for Children Medical Center-Lexington, Lexington, KY, USA Rita Ayyangar, MD  Department of Physical Medicine and Rehabilitation, Pediatric Rehabilitation Medicine, Faculty, Pediatric Palliative Care Stepping Stones Program, Michigan Medicine, Ann Arbor, MI, USA Nicole Bainton, RN, CPNP-PC  Division of Pediatric Orthopedic Center for Children, NYU Langone Orthopedic Hospital, New York, NY, USA Venkat  Boddapati, MD  Orthopedic Surgery, Columbia University Irving Medical Center, New York, NY, USA Angeline  Bowman, MD  Department of Physical Medicine and Rehabilitation, Pediatric Rehabilitation Medicine, Michigan Medicine, Ann Arbor, MI, USA Cory  Bryan, MD Pediatric Orthopedic Surgery, Shriners Hospital for Children, Greenville, SC, USA Henry G. Chambers, MD  University of California San Diego, San Diego, CA, USA Southern Family Cerebral Palsy Center, Rady Children’s Hospital San Diego, San Diego, CA, USA Reid  C.  Chambers, DO Nationwide Children’s Hospital, Ohio State University, Columbus, OH, USA Suzanne  Cherry, DPT Shriners Hospital for Children, Greenville, Greenville, SC, USA Emily  Dodwell, MD  Pediatric Orthopaedic Surgeon, Hospital for Special Surgery, Weill Cornell Medical College, New York, NY, USA Corinna  Franklin, MD Shriners Hospital for Children-Philadelphia, Philadelphia, PA, USA

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Michaela  Fraser, MS MPH OTR/L Department of Rehabilitation and Regenerative Medicine, Columbia University Irving Medical Center, New York, NY, USA Christine Goodbody, MD  Department of Orthopaedic Surgery, Hospital for Special Surgery, New York, NY, USA Heakyung  Kim, MD Pediatric Physical Medicine and Rehabilitation, Columbia University Irving Medical Center/New York Presbyterian Hospital, New York, NY, USA Jared Levin, MD  Pediatric Physical Medicine and Rehabilitation, Columbia University Irving Medical Center/New York Presbyterian Hospital, New York, NY, USA Lisa  Maskill, MD Helen DeVos Children’s Hospital, Grand Rapids, MI, USA Michigan State University School of Medicine, Grand Rapids, MI, USA Hiroko  Matsumoto, PhD Department of Orthopedic Surgery, Columbia University Irving Medical Center, New York, NY, USA Stacey Miller, BSc(PT), MRSc  Child Health BC Hip Surveillance Program for Children with Cerebral Palsy, BC Children’s Hospital, Vancouver, BC, Canada Kishore  Mulpuri, MD  Division of Pediatric Orthopedics, Department of Orthopaedics, Faculty of Medicine University of British Columbia, Vancouver, BC, Canada Nickolas  Nahm, MD Nemours A.I.  DuPont Hospital for Children, Wilmington, DE, USA Amber Newell, MSN, OTR/L, CPNP  Physical Medicine and Rehabilitation, Columbia University Irving Medical Center, New York, NY, USA Philip D. Nowicki, MD  Department of Orthopedics, Helen DeVos Children’s Hospital, Grand Rapids, MI, USA Kristan Pierz, MD  Center for Motion Analysis, Department of Orthopedic Surgery, Connecticut Children’s Medical Center, University of Connecticut School of Medicine, Farmington, CT, USA Eduardo  Del Rosario, PhD (student), FNP-BC Division of Pediatric Orthopedic Center for Children, NYU Langone Orthopedic Hospital, New York, NY, USA David  Roye, MD St. Giles Professor of Pediatric Orthopedic Surgery, New York Presbyterian Morgan Stanley Children’s Hospital, New York, NY, USA Weinberg Family Cerebral Palsy Center, New York, NY, USA David M.  Scher, MD Pediatric Orthopaedic Surgery, Department of Orthopaedic Surgery, Hospital for Special Surgery, New York, NY, USA

Contributors

Contributors

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Roshan P. Shah, MD  Columbia University, New York, NY, USA M.  Wade  Shrader, MD Division of Cerebral Palsy Department of Orthopedic Surgery, Nemours A.I. DuPont Hospital for Children, Wilmington, DE, USA Sara Silbert, MD Fellow, Pediatric Palliative Care Stepping Stones Program, Michigan Medicine, Ann Arbor, MI, USA Ernest Sink, MD  Center for Hip Preservation, Hospital for Special Surgery, New York-Presbyterian Hospital, Weill Cornell Medical College, New York, NY, USA Liana  Tedesco, MD Department of Orthopedic Surgery, Columbia University Irving Medical Center, New York, NY, USA Adam  Theissen, MD Pediatric Orthopedic Surgery, Texas Scottish Rite Hospital, Dallas, TX, USA Christian  Treat, MSPH Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA Arianna Trionfo, MD  St. Christopher’s Hospital for Children, Philadelphia, PA, USA Lisa  M.  Voss, DO  Pediatric Physical Medicine and Rehabilitation, Mary Free Bed Hospital, Grand Rapids, MI, USA J.  Turner  Vosseller, MD Department of Orthopedic Surgery, Columbia University Irving Medical Center, New York, NY, USA David  Westberry, MD Pediatric Orthopedic Surgery, Motion Analysis Center, Shriners Hospital for Children-Greenville, Greenville, SC, USA Hank  White, PT PhD Motion Analysis Center, Shriners Hospitals for Children Medical Center-Lexington, Lexington, KY, USA Lane Wimberly, MD  Texas Scottish Rite Hospital for Children, Dallas, TX, USA Orthopedic Surgery, UT Southwestern Medical Center, Dallas, TX, USA

1

Introduction to the Cerebral Palsies Henry G. Chambers and Reid C. Chambers

What Is Cerebral Palsy? Cerebral Palsy (CP) is not a disease, but rather a collection of disorders that have a brain malformation or injury as the final common pathway. There are many, including Sir William Osler, who describe this umbrella term “cerebral palsy” as the “cerebral palsies” to demonstrate the spectrum of this disorder [1]. Therefore, a strict definition of cerebral palsy is difficult at best. Anyone caring for a patient with CP will appreciate that a child who has mild toe walking is a completely different patient from one who is in a wheelchair, on a respirator and requires total care, yet these children both have “cerebral palsy.” In 2005, Bax and the Executive Committee for the Definition of Cerebral Palsy attempted to provide a comprehensive “new” definition of cerebral palsy [2]. Cerebral palsy (CP) describes a group of permanent disorders of the development of movement and posture, causing activity limitation, that are attributed to non-progressive disturbances that occurred in the developing fetal or infant brain.

H. G. Chambers (*) University of California San Diego, San Diego, CA, USA Southern Family Cerebral Palsy Center, Rady Children’s Hospital San Diego, San Diego, CA, USA R. C. Chambers Nationwide Children’s Hospital, Ohio State University, Columbus, OH, USA

The motor disorders of cerebral palsy are often accompanied by disturbances of sensation, perception, cognition, communication, behavior, by epilepsy and by secondary musculoskeletal problems

Richards and Malouin [3] added some more to the definition with some more clinically relevant considerations in their paper on cerebral palsy: CP is a disorder of the development of movement and posture, causing activity limitations attributed to nonprogressive disturbances of the fetal or infant brain that may also affect sensation, perception, cognition, communication, and behavior. Motor control during reaching, grasping, and walking are disturbed by spasticity, dyskinesia, hyperreflexia, excessive coactivation of antagonist muscles, retained developmental reactions, and secondary musculoskeletal, malformations together with pareses and defective programing. Weakness and hypoextensibility of the muscles are due not only to inadequate recruitment of motor units, but also to changes in mechanical stresses and hormonal factors.

In none of the recent definitions is there an age requirement, although it is generally accepted that any injury to the developing brain occurring prior to age 3 should be classified as cerebral palsy.

History of Cerebral Palsy I that am curtailed of this fair proportion, Cheated of feature by dissembling Nature, Deform’d, unfinish’d, sent before my time Into this breathing world, scarce half made up,

© Springer Nature Switzerland AG 2020 P. D. Nowicki (ed.), Orthopedic Care of Patients with Cerebral Palsy, https://doi.org/10.1007/978-3-030-46574-2_1

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H. G. Chambers and R. C. Chambers

2 And that so lamely and unfashionable, That dogs bark at me as I halt by them (Richard III, Act 1, Scene 1 Shakespeare)

William John Little (1810–1984) was one of the first to describe cerebral palsy and ascribed it to a brain injury caused by lack of oxygen at birth. Mr. Little was a sickly child and had many diseases including polio which left him with a clubfoot. He sought out Dr. Georg Friedrich Stromeyer who was a German surgeon. Dr. Strohmeyer performed a tendoachilles lengthening which helped Little immensely. He brought this procedure back to England where he helped establish the field of orthopedic surgery there. He then began his study of children and their “deformities.” In 1861, he presented his findings to the Obstetrical Society of London where he defined cerebral palsy as an obstetric injury in which “abnormal forms of labor” in which the “child has been partial suffocated” injures the nervous system [4]. He essentially defined Spastic Cerebral Palsy (but did not call it by that name) and it was called “Little’s Disease” for a very long time. There were dozens of other researchers throughout Europe who were describing this disorder with series of case reviews at the same time (Fig. 1.1). Sir William Osler (1849–1928) graduated from McGill University in 1872 and trained later in London and in Berlin with Rudolph Ludwig Karl Virchow. He was one of the first to use the term “cerebral palsy,” in his treatise: “The Cerebral Palsies of Children” in 1889. He had over 150 patients in this paper and was one of the first to use spastic hemiplegia and diplegia as subgroups. As one of the founders of Johns Hopkins University School of Medicine as well as one the founders of modern medical education, Professor Osler contributed much to the field of cerebral palsy and dozens of other fields. He published over 1200 manuscripts and books in his storied career [5] (Fig. 1.2). Sigmund Freud (1856–1939) is, of course, known for his contributions to the field of psychiatry. However, many are unaware of his contributions to the field of cerebral palsy. After his graduation from the University of Vienna in 1881, he spent an additional 3 years working in

Fig. 1.1  William John Little (1810–1894)

Fig. 1.2  Sir William Osler (1849–1919)

1  Introduction to the Cerebral Palsies

the field of neuroanatomy. He made several important discoveries which lead to the theory of the neuron. From 1885–1886, he worked with Jean-Marie Charcot and began his interest in clinical neurology. He returned to Berlin where he was appointed to care for children and adults with neurological deficits. Between 1891 and 1897, he published three monographs and several papers about children with cerebral palsy. The first manuscript was over 220 pages and had 180 references and exhaustively studied 35 patients. In 1893, he published a paper that was 168 pages long and had 53 cases. It was in this paper that he described “generalized cerebral spasticity: Littles Disease” (spastic diplegia), paraplegic spasticity (probably spastic quadriplegia), bilateral spastic hemiplegia, and, for the first time, choreoathetosis. He described ataxic cerebral palsy in a later paper. In 1897, he published a book entitled “Die infantile Cerebrallahmung” (Infantile Cerebral Paralysis) with over 327 pages. This was one of the first books to completely review what was known about cerebral palsy. He was one of the first to describe that, unlike Little who felt that cerebral palsy was secondary to birth trauma, it was some sort of insult to the developing brain and that the cause was unknown in most cases (Fig. 1.3). He lost interest in the field of cerebral palsy and began to develop the field of psychoanalysis. In a letter to Wilhelm Fliess, he complained “I am fully occupied with the children’s paralysis, in which I am not the least interested.” “The completely uninteresting work on children’s paralysis has taken all my time.” In a subsequent letter he recorded that he felt like “Pegasus yoked to the plough!” [5]. There was little interest in care of children with cerebral palsy throughout the world in the early twentieth Century. There was a multi-­ disciplinary clinic at Children’s Hospital in Boston under the neurologist, Bronson Crothers. Winthrop Phelps, an orthopedic surgeon, organized a rehabilitation center in Maryland. The rehabilitation movement that emerged from casualty management after World War II as well as the polio epidemic spurred the National Society for Crippled Children and Adults (Easter Seal

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Fig. 1.3  Sigmund Freud (1856–1939) Halberstadt, Max (c. 1921). “Sigmund Freud, half-length portrait, facing left, holding cigar in right hand.” Library of Congress. Archive

Society) to set up a CP Advisory Medical Council which included Earl Carlson (internal medicine), Bronson Crothers (neurology), George Deaver (rehabilitation medicine), Temple Fay (neurosurgery), Meyer Perlstein (pediatrics), and Winthrop Phelps (orthopedic surgery). In 1947, they formed the American Academy for Cerebral Palsy, which was an interdisciplinary group dedicated to the study of children with cerebral palsy. Now the American Academy for Cerebral Palsy and Developmental Medicine is one of the leading voices in the care of children and adults with cerebral palsy and other neurologic disorders (Fig. 1.4). Outstanding research is being performed throughout the world in an attempt to discover the etiology of the cerebral palsies as well as the best treatments for those who have this disorder. Patient registries in Scandinavia and Australia will provide more insight into the lon-

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H. G. Chambers and R. C. Chambers

Fig. 1.4 American Academy for Cerebral Palsy Founders. Seated: Temple Fay, Winthrop Phelps, Bronson Crothers. Standing: Meyer Perlstein, Earl Carlson, George Dever

gitudinal aspects of this disorder. In the past 30 years, management of spasticity and dystonia with oral medications, botulinum toxins, and intrathecal baclofen have greatly altered the treatment and outcomes of patients with cerebral palsy. Motion analysis has helped spur further biomechanical research and new orthopedic surgery techniques have been validated using this technology.

Epidemiology of the Cerebral Palsies The incidence and prevalence of cerebral palsy has not changed much in the past 50  years. However, the types of cerebral palsy and etiologies have changed over the years. Several long-­ term registry-based studies have determined that the prevalence ranges from 1.6 per 1000 live births to 3.6 per 1000 live births [6–11]. In other terms, this is 1 in 277 to 1 in 625 live births. Males are at a higher risk for cerebral palsy, possibly secondary to gender-specific neuronal vulnerabilities [12]. There is a higher incidence of cerebral palsy in very low birthweight and very premature babies (Table  1.1). This has changed over the past 30 years as we have developed neonatal intensive care centers which are

Table 1.1  Etiologic Risk Factors in Cerebral Palsy, as found in Blair [1] Prematurity Multiple births Older parents Parental consanguinity Social disadvantage Maternal thrombophilia Prior reproductive loss Maternal thyroid problems Pregnancy conditions  Severe antepartum hemorrhage  Preeclampsia  Cytomegalovirus and other infections  Infections of the fetal membranes Infants born late Birth trauma/asphyxia Chromosomal and brain abnormalities Metabolic influences  Hormonal  Inflammation Epigenetic factors such as maternal depression Infarcts

very proficient in keeping these children alive. In fact, mechanical ventilation in these premature children may contribute to their cerebral palsy [13]. The risk of cerebral palsy increases four times in twins and 18 times in triplets [14, 15]. There are now more adults with cerebral palsy than there are children.

1  Introduction to the Cerebral Palsies

In most cases the cause of cerebral palsy is not known.

Pathophysiology The unifying pathology of cerebral palsy is injury to the developing brain. There are several different insults that can lead to cerebral palsy. Most of the injuries occur near the periventricular region (Fig. 1.5). It is in this area where the pyramidal tracts traverse the brain. It is also the area where the basal ganglia are located. Injury to the cortical spinal tracts affects motor signals to the body, and the basal ganglia are responsible for encoding motor patterns. Their main function is to initiate and permit smooth performance of motor movements. Injury to the basal ganglia can lead to dystonia and choreoathetosis. Balance and the integration of motion can be affected by injury to the cerebellum or the tracts which lead to and from the cerebellum. Damage to the cerebellum can lead to the loss of ­coordination between muscle groups on both the contralateral and ipsilateral sides of the body. The brainstem nuclei can also be involved in cerebral palsy. In patients with more severe cerebral palsy (particularly GMFCS V patients), there can be pseudobulbar palsy. The cardinal features of this disorder are loss of emotional control (with forced crying or laughing), increased drooling, slow eating, choking, and speech abnormalities [16]. Fig. 1.5  Injury to the brain at any level can lead to cerebral palsy (after Gage, Schwartz, Koop, and Novacheck. The Identification and Treatment of Gait Problems in Cerebral Palsy. Clinics in Developmental Medicine 180–181, 2009)

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As mentioned in the definition of cerebral palsy above, visual disturbances are present in over half of the patients with cerebral palsy. This is secondary to the brain injury itself, involvement of the peripheral visual structures or a combination of both [17]. This can have a huge impact on the treatment of children and adults with cerebral palsy. For example, if someone is unable to see the ground ahead of them, any orthopedic surgery will not improve the patient’s gait. A change in pattern of the floor or of the walls may affect their ability to perceive their position in space. If, for example, they are unable to see their left side secondary to a hemiplegic stroke to the visual cortex, then any upper extremity intervention may not succeed as the patient cannot see their left upper extremity. This brain insult leads to an upper motor neuron syndrome. In simplistic terms, the main neurotransmitter from the brain (gamma-aminobutyric acid (GABA)) acts as an inhibitor and modulator of the reflex arc whose primary neurotransmitter is acetylcholine (Fig.  1.6). When there is an interruption of the brain’s main neurotransmitter, there are several “Positive Signs.” These include spasticity, hyperreflexia, dyskinesia, persistent primitive reflexes, and secondary musculoskeletal malformations. “Negative Signs” reflect the loss of proper sensorimotor control mechanisms leading to poor balance, incoordination, weakness, and impaired walking ability. Other problems that are present in children with cerebral palsy are loss of selective

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H. G. Chambers and R. C. Chambers

Fig. 1.6  The reflex arc. The reflex arc is not damaged in cerebral palsy, but the inhibitory and modulating influences of the brain are. This leads to the development of spasticity

motor control, sensory deficits, delayed growth and development and seizure disorders.

Classification Systems Classification systems can be geographic (part of the body involved) and the listing of the primary motor deficit. For example, “Spastic

Quadriplegia.” As mentioned in the history section above, the classifications of diplegia, hemiplegia, double hemiplegia, and quadriplegia (tetraplegia) were made over a hundred years ago [18]. The intraobserver and interobserver error in the use of this classification scheme is very high. In 1997, Palisano et al. [19] published one of the key articles in the understanding of cerebral palsy. In this article they described the use of the

1  Introduction to the Cerebral Palsies

Gross Motor Function test to delineate the severity of cerebral palsy. When the data of 275 children who were followed longitudinally were plotted, it was noted that the graphs showed five fairly discrete levels of motor function. Wood and Rosenbaum [20] further studied these groups and developed the Gross Motor Functional Classification System (GMFCS). This system has been expanded and revised to include children and adults to age 23. The GMFCS has become the standard in classifying children and adults with cerebral palsy. It is being validated in other conditions such as spina bifida and muscle disease as well. There are two main points to be made about the GMFCS based on the GMFM.  One, is that all children from GMFCS I to V all improve until they are about 6 years old, so any intervention that is done during this time will appear to improve the function of that child. It is really just mimicking natural history. The other aspect is that the GMFCS is not an outcome measure. One is on their level based on the involvement of their brain injury. The goal of surgery is to maintain the child at the level that they were at age 7,8, or 9. So when a teenager loses function and surgery makes them appear to improve a level, it is most likely just returning them to their highest function.

 Practical Guide to the GMFCS A Levels • Level I: These are the children with the least amount of involvement. They may have some problems with uneven ground and balance issues but otherwise can walk and run with minimal problems. • Level II: Children who can walk and run but have more problems especially when ascending and descending stairs. In the First World, children who are using AFOs are usually at this level. In the Third World, children who need AFOs are in this group. • Level III: Children can walk on a level surface, they usually are using AFOs as well, but this group does not have the strength or balance to walk without support. These children are

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using crutches or walkers to walk but for long distances they often use manually powered wheelchairs. • Level IV: These children cannot walk except with maximum support using a walker. They have the upper extremity control to use a powered wheelchair. • Level V: These children have severe physical impairment. They require total care and are dependent on others for transportation (Fig. 1.7).

Functional Mobility Scale Graham et al. [21, 22] developed the Functional Mobility Scale as an outcome measure for intervention such as surgery. It is very similar to the GMFCS although Level 6 is the highest functioning level. It assesses the patient to determine what function they have at 5, 50, and 500 meters. We all know of patients who can walk in the clinic without crutches, need crutches to walk 50 meters, but use a wheelchair for long distances (Fig. 1.8): 1. Uses wheelchair, stroller, or buggy: May stand for transfers and may do some stepping supported by another person or using a walker/ frame 2. Uses Walker: without help from another person 3. Uses two crutches: without help from another person 4. Uses one crutch or two canes: without help from another person 5. Independent on level surfaces: does not use walking aids or need help from another person. If uses furniture, walls, fences, shop fronts for support use 4 above 6. Independent on all surfaces: does not use any walking aids or need any help from another person when walking, running, climbing slopes and stairs. The Surveillance of Cerebral Palsy in Europe (SCPE) is a group of medical professionals who have used registry-based data to ascertain their

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H. G. Chambers and R. C. Chambers

Fig. 1.7  The Gross Motor Classification Scale. (Used with the permission of H. Kerr Graham, MD)

1  Introduction to the Cerebral Palsies

Rating

9

Rating

6

3

Independent on all surfaces:

Uses crutches:

Does not use any walking aids or need any help from another person when walking over all surfaces including uneven ground, curbs etc. and in a crowded environment.

Without help from another person.

Rating

Rating

5

2

Independent on level surfaces:

Uses a walker or frame:

Does not use walking aids or need help from another person.* Requires a rail for stairs.

Without help from another person.

* If uses furniture, walls, fences, shop fronts for support, please use 4 as the appropriate description.

Rating

Rating

4

1

Uses sticks (one or two):

Uses wheelchair:

Without help from another person.

May stand for transfer, may do some stepping supported by another person or using a walker/frame.

Walking distance

Rating: select the number (from 1−6) which best describes current function

5 metres (yards) 50 metres (yards)

Rating

C Rating

N

Crawling: Child crawls for mobility at home (5m).

N = does not apply: For example child does not complete the distance (500 m).

500 metres (yards)

Fig. 1.8  The Functional Mobility Scale. (Used with the permission of H. Kerr Graham, MD)

population. Through various consensus groups they have determined that they have classified children with cerebral palsy based on the following criteria: Spastic CP is characterized by at least two of the following:

• Abnormal pattern of posture and/or movement • Increased tone (not necessarily constant) • Pathological reflexes (increased reflexes: hyperreflexia and/or pyramidal signs, e.g., Babinski sign

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H. G. Chambers and R. C. Chambers

• • • • • • • •

• Level 4: Handles a limited selection of easily managed objects in adapted situations • Level 5: Does not handle objects and has severely limited ability to perform even simple tasks There are other classification systems of which orthopedic surgeons should be aware: The Communication Function Classification System [25] and the Visual Function Classification System [17].

Spastic CP may be either bilateral or unilateral Spastic bilateral CP is diagnosed if: Limbs on both sides of the body are involved Spastic unilateral CP is diagnosed if: Limbs on one side of the body are involved Ataxic CP is characterized by both: Abnormal pattern of posture and/or movement Loss of orderly muscular control so that movements are performed with abnormal force, rhythm, and accuracy • Dyskinetic CP is dominated by both: • Abnormal pattern of posture and/or movement • Involuntary uncontrolled, recurring, occasionally stereotyped movements • Dyskinetic CP may be either dystonic or choreoathetotic • Dystonic CP is dominated by both • Hypokinesia (reduced activity, i.e., stiff movement) • Hypertonia • Choreoatheototic CP is dominated by both: • Hyperkinesia (increased activity, i.e., stormy movement) • Hypotonia This is a consensus statement from a group of researchers who have carefully reviewed their registry data [23]. Although this system has been widely adopted, it is clear to many clinicians that the unilateral vs. bilateral classification is too simple. Many children with “Unilateral CP” have involvement of their opposite sides. There are fewer but possibly more patients with triplegia than is commonly appreciated.

Manual Ability Classification System While the GMFCS is used almost universally, it is only part of the story as it explicitly evaluates walking ability. The Manual Ability Classification System (MACS) was developed to determine upper extremity function [24]. • Level 1: Handles objects easily and successfully • Level 2: Handles objects, but with somewhat reduced quality and/or speed of achievement • Level 3: Handles objects with difficulty; needs help to prepare and/or modify activities

Conclusion This brief introduction to cerebral palsy will, I hope, set the stage for the remainder of this book. As you read of the different interventions, treatments, and rehabilitation, recall the different classification systems and try to relate that to your patient. Every brain lesion is subtly different, every movement disorder is subtly different, and every deformity is subtly different. Each patient needs to be treated as an individual and cannot be lumped into a single broad category.

References 1. Blair E. Epidemiology of the cerebral palsies. Orthop Clin North Am. 2010;41(4):441–55. https://doi. org/10.1016/j.ocl.2010.06.004. 2. Bax M, Goldstein M, Rosenbaum P, Leviton A, Paneth N, Dan B, et al. Proposed definition and classification of cerebral palsy, April 2005. Dev Med Child Neurol. 2005;47(8):571–6. Retrieved from https://www.ncbi. nlm.nih.gov/pubmed/16108461. 3. Richards CL, Malouin F.  Cerebral palsy: definition, assessment and rehabilitation. Handb Clin Neurol. 2013;111:183–95. https://doi.org/10.1016/ B978-0-444-52891-9.00018-X. 4. Schleichkorn J.  The sometime physician: William John Little pioneer in treatment of cerebral palsy and orthopedic surgery 1810–1894. Tunbridge Wells: Aquarian Systems; 1999. 5. Longo LD, Ashwal S.  William Osler, Sigmund Freud and the evolution of ideas concerning cerebral palsy. J Hist Neurosci. 1993;2(4):255–82. https://doi. org/10.1080/09647049309525576. 6. Andersen GL, Irgens LM, Haagaas I, Skranes JS, Meberg AE, Vik T.  Cerebral palsy in Norway: prevalence, subtypes and severity. Eur J Paediatr Neurol. 2008;12(1):4–13. https://doi.org/10.1016/j. ejpn.2007.05.001.

1  Introduction to the Cerebral Palsies 7. Himmelmann K, Hagberg G, Beckung E, Hagberg B, Uvebrant P. The changing panorama of cerebral palsy in Sweden. IX. Prevalence and origin in the birth-year period 1995–1998. Acta Paediatr. 2005;94(3):287–94. https://doi.org/10.1111/j.1651-2227.2005.tb03071.x. 8. Smith L, Kelly KD, Prkachin G, Voaklander DC. The prevalence of cerebral palsy in British Columbia, 1991–1995. Can J Neurol Sci. 2008;35(3):342–7. Retrieved from https://www.ncbi.nlm.nih.gov/ pubmed/18714803. 9. Gainsborough M, Surman G, Maestri G, Colver A, Cans C.  Validity and reliability of the guidelines of the surveillance of cerebral palsy in Europe for the classification of cerebral palsy. Dev Med Child Neurol. 2008;50(11):828–31. Retrieved from https:// www.ncbi.nlm.nih.gov/pubmed/19058397. 10. Howard J, Soo B, Graham HK, Boyd RN, Reid S, Lanigan A, et  al. Cerebral palsy in Victoria: motor types, topography and gross motor function. J Paediatr Child Health. 2005;41(9–10):479–83. https://doi. org/10.1111/j.1440-1754.2005.00687.x. 11. Yeargin-Allsopp M, Van Naarden Braun K, Doernberg NS, Benedict RE, Kirby RS, Durkin MS. Prevalence of cerebral palsy in 8-year-old children in three areas of the United States in 2002: a multisite collaboration. Pediatrics. 2008;121(3):547–54. https://doi. org/10.1542/peds.2007-1270. 12. Johnston MV, Hagberg H. Sex and the pathogenesis of cerebral palsy. Dev Med Child Neurol. 2007;49(1):74– 8. https://doi.org/10.1111/j.1469-8749.2007.0199a.x. 13. Aly H.  Mechanical ventilation and cerebral palsy. Pediatrics. 2005;115(6):1765–7. https://doi. org/10.1542/peds.2005-0665. 14. Scher AI, Petterson B, Blair E, Ellenberg JH, Grether JK, Haan E, et  al. The risk of mortality or cerebral palsy in twins: a collaborative population-based study. Pediatr Res. 2002;52(5):671–81. https://doi. org/10.1203/00006450-200211000-00011. 15. Topp M, Huusom LD, Langhoff-Roos J, Delhumeau C, Hutton JL, Dolk H, SCPE Collaborative Group. Multiple birth and cerebral palsy in Europe: a multicenter study. Acta Obstet Gynecol Scand. 2004;83(6):548–53. https://doi. org/10.1111/j.0001-6349.2004.00545.x. 16. Langworthy OR, a. H. F. Syndrome of pseudobulbar palsy. Arch Intern Med (Chic). 1940;65:106–21.

11 17. Baranello G, Signorini S, Tinelli F, Guzzetta A, Pagliano E, Rossi A, et al.. Visual function classification system for children with cerebral palsy: development and validation. Dev Med Child Neurol. 2019. https://doi.org/10.1111/dmcn.14270. 18. Minear WL.  A classification of cerebral palsy. Pediatrics. 1956;18(5):841–52. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/13370256. 19. Palisano R, Rosenbaum P, Walter S, Russell D, Wood E, Galuppi B. Development and reliability of a system to classify gross motor function in children with cerebral palsy. Dev Med Child Neurol. 1997;39(4):214– 23. Retrieved from https://www.ncbi.nlm.nih.gov/ pubmed/9183258. 20. Wood E, Rosenbaum P.  The gross motor function classification system for cerebral palsy: a study of reliability and stability over time. Dev Med Child Neurol. 2000;42(5):292–6. Retrieved from https:// www.ncbi.nlm.nih.gov/pubmed/10855648. 21. Graham HK, Harvey A, Rodda J, Nattrass GR, Pirpiris M.  The functional mobility scale (FMS). J Pediatr Orthop. 2004;24(5):514–20. Retrieved from https:// www.ncbi.nlm.nih.gov/pubmed/15308901. 22. Surveillance of Cerebral Palsy in Europe. Surveillance of cerebral palsy in Europe: a collaboration of cerebral palsy surveys and registers. Dev Med Child Neurol. 2000;42:816–24. 23. Eliasson AC, Krumlinde-Sundholm L, Rosblad B, Beckung E, Arner M, Ohrvall AM, Rosenbaum P. The Manual Ability Classification System (MACS) for children with cerebral palsy: scale development and evidence of validity and reliability. Dev Med Child Neurol. 2006;48(7):549–54. https://doi.org/10.1017/ S0012162206001162. 24. Barty E, Caynes K, Johnston LM. Development and reliability of the functional communication classification system for children with cerebral palsy. Dev Med Child Neurol. 2016;58(10):1036–41. https://doi. org/10.1111/dmcn.13124. 25. Harvey A, Graham HK, Morris ME, Baker R, Wolfe R.  The functional mobility scale: ability to detect change following single event multilevel surgery. Dev Med Child Neurol. 2007;49(8):603–7. https://doi. org/10.1111/j.1469-8749.2007.00603.x.

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Principles of Orthotics and Other Durable Medical Equipment Lisa M. Voss

Orthotic Principles Writing an Orthotic Prescription Several different things must be taken into account when writing an orthotic prescription. For example, we must first have a goal. Examples include a goal of improved range of motion, minimizing contractures, proper positioning while seated, or improving active ambulation. Goals may change depending on the age of the patient and his/her individual needs at the time, and it is critical to include the patient and their family in the identification of the goal or goals. Time, age, and function will change patient’s goals. For the youngest patient, an improved range of motion with contracture prevention is in the forefront. As the patient ages, their goals often change to become more peer focused as they want to engage in the same activities and sports as their peers, and having adaptations to enable this becomes important. The physician must take into account the patient’s goals and educate the patient and family in regard to appropriate medical goals for their overall health and find the appropriate balance. Once a goal is identified, the next step is deciding how to best achieve that goal. Different equipment and orthoses may be required to help L. M. Voss (*) Pediatric Physical Medicine and Rehabilitation, Mary Free Bed Hospital, Grand Rapids, MI, USA e-mail: [email protected]

achieve a goal, and for that, different shapes, sizes, styles, material, and even colors/decorations should be considered. Above all else, it should improve their quality of life.

Orthotic Design The goal of the proper orthotic design is one that will enhance proper movement while minimizing abnormal postures, movements, and tone. This is particularly important in cerebral palsy as patients are at high risk for joint contractures and deformities from spasticity, abnormal posturing/ dystonia, and skin breakdown. It is important to have this be our focus while also considering options to make the orthosis lightweight, easily manageable, durable, and personally stylized. The orthotic itself will not be beneficial if the patient is not willing to wear it, and therefore, taking style into account is also an important feature, especially in children and adolescents. When writing the prescription, it is important to include details such as the general description of the orthosis, the joints involved, and whether there should be motion in the joints. If an a­ rticulated joint is requested, the prescriber should note the range of motion desired and if any restrictions or stops should be placed. It is also important to include the amount of stability required for each individual patient. For example, some patients have sig-

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nificantly high tone or strength and may break a brace that is too flimsy. Conversely, a patient who is very weak would not be able to move in a brace that is too heavy and would not require the added force. A prescription for the orthotic itself should include the design type (custom vs off the shelf), laterality (left, right, bilateral), material, joints involved, and any specifications to tailor to the patient’s needs. Prescription example: Sig: Custom bilateral articulated thermoplastic AFOs with plantar flexion stop at neutral and free dorsiflexion and flexible forefoot with extra wide and extra depth shoes to accommodate bracing.

Material The material used should be chosen carefully allowing the brace to be both stable and provide appropriate support but remain lightweight enough to allow the patient to function easily. Currently, braces are made of thermoplastic molding which may be off the shelf or custom. Metal may be used as additional support and for the joints of a brace if articulated or if a patient is >250 lbs. Occasionally a brace may be made of carbon fiber. The goal of the brace must also be considered when determining the material. For example, if the brace is to be worn at night, it will require different material than a brace that must fit into shoes for day use. Similar adjustments will be made for different locations on the body. For example, a patient is less likely to tolerate an exclusively plastic brace on their hand or arm and will require some additional padding or have it made out of neoprene.

Upper Extremity Orthotics Goal It is imperative to note the goal of the orthotic when prescribing. For hands and arms, orthotics may be used to increase functionality or may be used for stretching and prevention of contracture.

Fig. 2.1  Standard WHO with thumb abduction (palmar view)

Sometimes, the same brace may provide both functions, but other times they are mutually exclusive. For this reason, it is important to have the discussion on timing and frequency of brace use and specific instruction on use to both the patient and the orthotist.

Brace Types Thumb Abduction Splint (Fig.  2.1)  Thumb abduction splints are typically used to abduct the thumb for stretching, maintenance of proper posture, and placing the thumb in a functional position. It is typically neoprene and will not overcome a severe cortical thumb. For infants, it may just be a thumb sleeve portion with a wrap-­ around strap, whereas for older children, the wrist may also be included. Wrist Hand Orthosis (WHO) (Fig.  2.2a, b)  A wrist hand orthosis crosses over the wrist joint and includes the hand. This may or may not have ability to bend at various angles for wrist and fingers. Some WHOs may be custom, while others are off the shelf. Fingers may be included if the prescriber desires. Resting Hand Splint  A resting hand splint is a balance between intrinsic and extrinsic musculature to prevent deformity. These are often used when patients are sleeping or resting as they are not typically functional.

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Fig. 2.2 (a, b) Custom wrist hand orthosis

Elbow Extension Splints/Bamboo Braces  These elbow braces are used to increase the extension on the elbow, predominantly used for stretching, and occasionally used in babies to assist with crawling and weight-bearing through arms. Larger extension splints may come with a dynamic hinge which allows for a graduated stretch at specific settings.

Lower Extremity Orthotics Goal The identification of the goals of the prescriber and the patient is the first thing that needs to occur. Lower extremity orthotics have multiple purposes such as improved positioning, pain relief, stretching, stability, standing, and/or ambulation. Some orthotics can serve multiple purposes simultaneously, while others are more specific. For example, an ankle foot orthosis (AFO) may provide improved stability and allow independent ambulation, while others may be designed specifically for stretching purposes but not intended to be used for ambulation.

Length Different lengths provide different forces and therefore provide different degrees of control of the body. It is important to choose an appropriate length that allows adequate but not excessive control as we want the patient to be as function-

Fig. 2.3  Bilateral UCBL foot orthotics

ally mobile as possible while minimizing limitations. The length is twofold in that it is the length up the calf/shin proximally as well as the length distally along the plantar aspect of the foot itself.

Types Foot Orthosis (FO)  There are multiple different options of foot orthoses used for proper positioning of the foot inside of the shoe, and they may be off the shelf or custom. The focus is on controlling the hindfoot, midfoot, and/or forefoot. A University of California Berkeley Labs (UCBL) orthotic (Fig.  2.3) has the most control that can be provided without extending above the shoe as it provides more firm calcaneal control and arch support. Other options include heel cups for shock absorption, midfoot orthoses for arch support, and metatarsal bars for metatarsalgia.

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Fig. 2.4 (a) Custom supramalleolar orthoses with full length foot plate. (b) Posterior view of SureStep™ SMOs with free toe to allow for flexion at phalangeal joints. (c) Anterior view of SureStep™ SMOs with free toe

Supramalleolar Orthosis (SMO) (Fig. 2.4a–c)  Supramalleolar orthoses are ankle orthoses that come just above the malleoli. These provide stability in the foot and ankle but not to the same degree as a full AFO.  These are typically used in children with very mild and intermittent toewalking gait or medial-lateral instability at subtalar joint, midfoot, or forefoot. It allows free dorsiflexion and plantar flexion which can be beneficial for a child who is learning to walk and spends a great deal of time crawling on the floor. Ankle Foot Orthosis (AFO)  The main goal of this orthosis is to provide stability through the ankle and subtalar joints. This can be accomplished by a variety of methods as noted in more detail below. Posterior Leaf Spring (PLS)  A PLS style of AFO provides the least amount of support but is the lightest weight and most appropriate for patients who have foot drop as it allows some flexibility in plantar flexion and is typically set in a few degrees of dorsiflexion to assist with

toe clearance. These are typically off the shelf and therefore can be obtained quickly. These can be fabricated from different materials such as thermoplastic or carbon fiber. The thermoplastic will flex more easily, while the carbon fiber will retain some of the energy and transfer a portion of the energy when pushing off from the ground. Solid Ankle (Fig.  2.5a, b)  The amount of support that is applied in a solid ankle AFO varies greatly and must be communicated to your orthotist to achieve the desired goal. The plastic may be semi-flexible or very rigid depending on the needs of the patient. In the case of significant spasticity, the AFO should be made firm. The ankle may be set in different positions to affect the gait and impact the knee. For example, dorsiflexion at the ankle creates knee flexion at heel strike, and plantar flexion at the ankle creates knee extension at heel strike. This must be ­considered when creating the orthotic and may be used to treat knee instability such as genu recurvatum. These AFOs may also be created

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Fig. 2.5 (a) Anterolateral view of custom solid ankle AFO. (b) Posterior view of custom solid ankle AFO

with a soft foam or silicone inner liner to provide extra skin protection or support depending on the needs of the patient.

a plantar flexion stop to prevent plantar flexion beyond a specific degree specified by the provider.

Articulated (Fig.  2.6a, b)  Articulated AFOs allow for motion at the ankle. It is the decision of the provider as to how much motion and in which direction to allow at the ankle, and this must be specified in the prescription. In a patient with strictly medial/lateral instability, the ankle may be allowed free dorsiflexion and plantar flexion range. A patient who fatigues over the day and whose gait becomes crouched may benefit from a check strap which allows adjustment in the amount of dorsiflexion allowed with continued free plantar flexion. For patients with significant plantar flexion spasticity, it is possible to allow for free dorsiflexion while placing

Ground Reaction (GRAFO) (Fig. 2.7)  Ground reaction AFOs work well for patients who ambulate with a crouched gait pattern as the ground reaction pushes up through the anterior cuff and shin of the patient providing an extension torque on the knee. This provides extra stability and supports promoting an upright posture. This does not work well if there is significant hamstring tightness and/or spasticity. Nighttime Stretching (Fig.  2.8)  Night splints may be with Ultraflex™ hinges or Velcro™ with anterior placement depending on the needs of the patient. The Ultraflex™ hinge allows for a pro-

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Fig. 2.6 (a) Custom articulated AFO lateral view. (b) Custom articulated AFO anterolateral view

Fig. 2.7  Ground reaction AFO

Fig. 2.8  Night brace with hinge

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gressive stretch (most typically in dorsiflexion) of the ankle where the Velcro™ is less dynamic. Both require the use of a knee immobilizer in order to stretch the gastrocnemius which is most commonly tightened. These are typically worn at night when sleeping to allow a prolonged stretch during times of peak growth. There is typically grip placed on the sole to allow for brief ambulation such as nighttime trips to the bathroom. Knee Ankle Foot Orthosis (KAFO) (Fig. 2.9)  KAFOs are often used for ambulation and/or exercise and can assist in the prevention of joint contractures. The knees may be jointed or locked depending on the needs of the patient and the strength of the quadriceps and hamstrings. They require a significant amount of energy expenditure and therefore are not typically used for routine ambulation and very rarely for lengthy distances. Because of the added weight and therefore strength required in an already compromised limb, these can be very tricky to learn to use and typically require the assistance of a physical therapist to train the patient and family on how to use appropriately. The use of a KAFO is excellent for exercise purposes along with improved bone health and growth due to active weight-bearing through the long bone(s). Hip-Knee-Ankle-Foot Orthosis (HKAFO)  An HKAFO has both a hip belt and joint which may be locked or mobile along with the knee. As a patient progresses, more of the joints may become unlocked. Again, this is often cumbersome and used mostly for exercise and bone health purposes but typically not for routine mobility although there are some rare exceptions. Reciprocating Gait Orthosis (RGO) (Fig. 2.10a, b)  Once a child has obtained good trunk control and coordination while using a standing frame and advanced to ambulation, a reciprocating gait orthosis may be beneficial to them as this provides contralateral hip extension with ipsilateral hip flexion. This is typically used by children aged 3–6 years who have the ability to activate hip flexion but have weak or poor hip extension. Once again, it is not often used for functional ambula-

Fig. 2.9  Knee ankle foot orthosis

tion as it is very energy demanding and the patient will fatigue quickly.

Durable Medical Equipment (DME) Goal For DME, like orthoses, the goal must be identified prior to prescription for any durable medical equipment. The key feature of DME is centered first around safety and second around independence. Both of these must be taken into account when writing a prescription. It is not uncommon for the patient to have one type of DME that provides a higher level

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Fig. 2.10 (a) Lateral view of reciprocating gait orthosis (RGO). (b) Anterior view of reciprocating gait orthosis (RGO)

of safety and stability while working in therapy to progress to the next level with less intervention.

Writing a Prescription Once the goal is identified, a prescription can be written to either a physical therapist for further evaluation and fitting or to a DME provider if you are knowledgeable of specifics. For items that are not customized, you may write the prescription to the DME provider itself specifying the item that you desire for the patient, the frequency of use you desire, and any specifics about the item that you desire. One way to ensure a good fit, function, and use of a piece of DME is to have the assistance of

a physical therapist. They are specially trained to fit the equipment to the patient with full measuring and often have some equipment the patient may try prior to purchase. In addition, the therapist assists after attaining the item for further education and training. Each piece of DME may have specific add-ons, attachments, or other items that can be specially adapted to help your patient function.

Types of DME Wheelchair Resembling the diverse needs of the cerebral palsy patients themselves, wheelchairs come in a

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deformity such as scoliosis or kyphosis including the special three-point pressure technique for scoliosis management providing appropriate support pads. These custom-molded systems (Fig.  2.12a, b) provide maximum support for patients with fixed deformities but are expensive and limit the types of seating systems available. It is also critical that if patients lack sensation, these specialty seating systems accommodate for this with specialty cushions alleviating pressure that would cause skin breakdown. It is also important in this case to have a tilt in space wheelchair to allow for adequate pressure relief. For patients who do not require a completely motorized wheelchair, there are additional options such as the power assist chair (Fig. 2.13) which can provide some assistance but not complete motor control. This can be set individually from one side or both at differing amounts depending on the patient’s ability to move. This can be particularly helpful if the patient has hemiparesis. When writing a prescription for a wheelchair, it is important to note the following basics: Fig. 2.11  Manual wheelchair

variety of different types to meet all the various needs of the patient. Wheelchairs can be a standard manual wheelchair (Fig. 2.11) without any electronic components or may be completely motorized power wheelchairs that can even be driven with the slight movement of a head or “sip and puff” system. Again, it is a delicate balance to meet, but not exceed, the needs of the patient. We want to be sure to give him/her adequate support without providing excessive support while meeting their medical needs. As always, we want our patients to be functional and therefore will need to be in a functional position in their seating systems. For people who require more specialized mobility systems, a wheelchair can be fabricated with a specialty seating system that allows accommodations for their altered positioning such as scoliosis and contractures. Special support must be provided for patients with a spinal

• Seat: custom (for deformities or sensory impaired) vs standard • Positioning: tilt in space (required for pressure relief for patients with impaired sensation) vs standard • Mobility: power (motorized driven by various options) vs power assist (patient able to provide some assistance in propelling) vs manual (propelled by patient) The assistance of a physical therapist may be extremely beneficial to help identify additional specialty features. Adaptive Stroller (Fig.  2.14)  An adaptive stroller is similar to a wheelchair but is significantly lighter and more portable and frequently will fold up for easy transportation in and out of cars; however, a patient cannot propel it independently. Canes  Canes are available in many different types and sizes with a variety of end structures

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Fig. 2.12 (a, b) Custom power wheelchair

Fig. 2.13  Power assist wheelchair

Fig. 2.14  Adaptive stroller

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Fig. 2.15 (a) Quad cane. (b) Bilateral tripod canes

from single point to multiple points (i.e., tripod (Fig. 2.15a) or quad cane (Fig. 2.15b)). These differ in the amount of support that they can provide the patient. Although the single-point cane can most closely resemble the normal gait cycle, it does not provide as much support as a cane with more than a single point would such as the quad cane. When prescribing a cane, please note the type of end desired. Crutches  Crutches are typically one of two types. One type is axillary crutches (Fig. 2.16a), and they are often used with broken legs and require significant wrist and hand use. The other type is Lofstrand (forearm) crutches (Fig. 2.16b). These forearm crutches may have different styles

and allow the patient to be able to reach with his/ her hands without losing the crutch. Similar to canes, crutches have a variety of different ends available. Walkers  Walkers may come in either forward or reverse. Forward walkers are what people consider as traditional and maybe with or without wheels. Unfortunately, these do tend to promote hip and trunk flexion which is not ideal in the cerebral palsy population as they tend to have very tight hip flexors. Reverse walkers (Fig. 2.17a, b), on the other hand, promote a more upright posture which typically is preferred in this population if tolerated. Walkers are typically very modifiable and may have various accessories or

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Fig. 2.16 (a) Axillary crutches. (b) Lofstrand/forearm crutches

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Fig. 2.17 (a, b) Pediatric reverse walker

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attachments to meet the needs of the patient. Some of these modifications include the ability to have forearm attachments, baskets, seats, and brakes, and they may come in a variety of colors. Although walkers allow the ability to ambulate a

b

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Fig. 2.18 (a–c) Gait trainers of varying sizes and supports

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with support, they do not control the trunk or pelvis. Gait Trainers (Fig. 2.18a–c)  Gait trainers are similar to walkers in that they may allow an

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Fig. 2.19 (a, b) Free standing ladders

individual support to ambulate; however, gait trainers provide significantly more support to an individual. A gait trainer can provide significant trunk and pelvic support along with seats, slings, and other attachments that can further support the body. The idea is not to support the entire weight of the body but to provide stabilization and support while teaching a reciprocal gait pattern in the standing position. In addition to providing mobility, these also assist with general health including gastrointestinal and bone health. Lifts/Hoyer Lifts  There are different types of lifts that can help move a patient from one location to another such as from bed to wheelchair or to a commode. Some lifts may be hydraulic (requiring significant caregiver effort), while others are electric (more expensive but less burden on a caregiver). There are some transfer lift sys-

tems that are motorized and include a permanent track in a ceiling mount, while others are self-­ contained and are on wheels to be pushed by a caregiver. Lifts have different slings that can provide different support and assistance depending on the patient’s need. Transfer Boards/Trapeze Bars/Free Standing Ladders  Not all people will require the use of a lift as some still may bear weight and assist with a transfer. If this is the case, a transfer board can be of significant benefit to allow patient independence. In addition, trapeze bars may be attached to a bed frame and allow improved bed mobility and positioning changes. Free-standing ladders (Fig.  2.19a, b) are often used for the patient to come to a standing position and assist with transfers or hygiene by remaining in a standing position with the assistance of the ladder.

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Stander  Standers (Fig. 2.20a–d) are particularly important for people with cerebral palsy who are not able to stand without support and are used for overall body health including bone strength, sus-

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tained muscular stretching, and gastrointestinal motility. The goal is to use it a few times a day for a total of 1  h typically split into 20–30-minute sessions. This time should not replace active

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Fig. 2.20 (a, b) Stander with tray . (c, d) Stander without tray

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mobility exploring the environment. There are numerous different options for standards with all different types of support depending on the individuals’ needs.

L. M. Voss Acknowledgment The photographs were obtained by Shauna Thomas, CPO; Micah Huegel, DPT; Andrea Dennis, DPT; and Lisa M. Voss, DO.

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Spasticity Management: Nonoperative and Operative Heakyung Kim, Eduardo Del Rosario, Richard Anderson, Nicole Bainton, Jared Levin, and Angeline Bowman

Introduction Spasticity is one of the most common motor control disorders found in patients with cerebral palsy (CP), present in up to 90% of cases. Children with CP may have concomitant extrapyramidal tract involvement causing additional movement disorders such as dystonia, ataxia, flaccidity, chorea, and athetosis [1]. Spasticity is a velocity-dependent increased muscle tone, secondary to decreased inhibition of the musculotendinous stretch reflex from upper motor neuron disease or injuries [2].

H. Kim (*) ∙ J. Levin Pediatric Physical Medicine and Rehabilitation, Columbia University Irving Medical Center/New York Presbyterian Hospital, New York, NY, USA e-mail: [email protected] E. Del Rosario · N. Bainton Division of Pediatric Orthopedic Center for Children, NYU Langone Orthopedic Hospital, New York, NY, USA R. Anderson Division of Pediatric Neurosurgery, Columbia University Irving Medical Center, New York, NY, USA A. Bowman Department of Physical Medicine and Rehabilitation, Pediatric Rehabilitation Medicine, Michigan Medicine, Ann Arbor, MI, USA

Spasticity can impair motor function, cause pain, and deteriorate quality of life. There are many different types of spasticity management although none of them are perfect. Nonpharmacological intervention includes physical and occupational therapy, splinting, casting, orthotics, and electrical stimulation. Pharmacological interventions are oral medications and intrathecal baclofen. Procedures such as botulinum toxin injection or chemical neurolysis can be performed to help control focal spasticity. Moreover, neurosurgical interventions such as Selective Dorsal Rhizotomy for spasticity in lower limbs and intrathecal baclofen pump placement for severe diffuse spasticity or dystonia can be considered. This chapter discusses various forms of spasticity management and will serve to educate on how to select the best treatment for each individual patient. Spasticity management is challenging, and no standard approach exists. There are special considerations for pediatric spasticity management, required for successful control of tone. Clinicians need to consider the following in each patient to decide on the appropriate management for pediatric spasticity: severity of spasticity, age, size, or weight of the patient, timing and goals of spasticity management, functional status, family support and resources, compliance of caretakers, and geographic limitations. A major difference between adults and children in terms of spasticity management is that children grow. In normal growing children,

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their muscles and bones grow at the same ratio. However, the muscles of children with spasticity are generally shorter, smaller, and cannot catch up with their bone growth. Such discrepancy between bones and spastic muscles gets worse during growth spurts, leading to increased stimulation of the stretch reflex and worsening spasticity. Close follow-up throughout a child’s growth is critical to prevent secondary complications. In general, unmanaged spasticity will worsen in severity over time, leading to joint contracture, and it is recommended that patients receive early and appropriately aggressive management to maximize long-term outcomes. When attempting to accurately manage spasticity, it is important to differentiate spasticity from other forms of increased tone, and from musculotendinous contracture.

Contracture Contractures are a near-permanent shortening of the musculotendinous apparatus due to atrophy and lack of regular stretching. Contracture will not be velocity dependent and should not be managed in the same way as spasticity. One can differentiate contractures from severe spasticity by using sedation/anesthesia or local anesthetic nerve block. A contracted joint will not show improved passive range of motion under sedation/anesthesia or after local anesthetic nerve block. The best treatment option could be orthopedic surgical intervention and serial castings to treat a contracted joint. There are multiple exams and scales that can be used to evaluate spasticity, which are largely examiner dependent, and will be discussed below.

Dystonia Dystonia is made up of sustained, involuntary, directional muscle contractions resulting in abnormal movements or postures. Compared to spasticity, dystonia often waxes and wanes. Dystonia is often initiated or worsened by voluntary action and associated with overflow muscle activation.

Clonus Clonus is involuntary repeated focal muscle contractions and relaxation caused by the same dysregulated stretch response that triggers spasticity. Clonus is often present in patients with spasticity, and can last for only a few beats, or can be sustained based on severity. Clonus of the ankle can limit a patient’s ability to be braced, stand, or ambulate, and clonus of the wrist can limit manual tasks. Clonus can be managed via the same modalities as spasticity.

Evaluating Spasticity with the Physical Exam The physical exam is paramount in the diagnosis and management of spasticity. It is important to differentiate between spasticity, other forms of abnormal tone, and contracture, as management will change depending on the pathology. The exam can also be used to monitor changes in tone, necessary for adjusting management over time. The practitioner who will be treating patients with spasticity should be comfortable with the various forms of examination listed below.

Range of Motion Range of motion (ROM) defines the degrees of movement available in a joint in a single dimensional plane (e.g. sagittal, coronal, or transverse). Measuring ROM and knowing the normal values of ROM in a joint are essential when assessing a patient’s spasticity. There are two different types of range of motion that are measured; active and passive. Active range of motion (AROM) is the ROM that the patient is able to physically obtain themselves, and is thus strength- and cognition dependent. Passive range of motion (PROM) is the ROM that the examiner is able to physically move the patient into without the patient’s assistance. A loss of ROM can affect a patient’s comfort, functional capacity, and ease of care. As uncontrolled spasticity will gradually worsen the

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ROM in a joint, tracking ROM becomes very important in spasticity evaluation and management. For the most reliable results, one should use a goniometer to measure ROM angles. A detailed description of how to evaluate ROM is provided in the appendix.

Hypertonia Evaluation Tools The spasticity evaluation tools that are commonly used are the Modified Ashworth Scale (MAS) and the Modified Tardieu Scale (MTS). A more quantifiable measurement for spasticity was developed by Tardieu and may benefit more than MAS by better differentiation of contractures from spasticity [3]. To differentiate hypertonicity between spasticity versus dystonia versus rigidity, the Hypertonia Assessment Tool (HAT) is frequently used [4].

 odified Ashworth Scale M The MAS is a physical exam tool used to assess the severity of spasticity in a muscle or joint. The MAS was designed exclusively for the evaluation of spasticity. It has been found to have satisfactory inter- and intra-rater agreement. It has been shown to be more useful in assessing spasticity in the upper extremities, compared to the lowers [5]. For a detailed description of how to perform the MAS test, please see the appendix. Modified Tardieu Scale The MTS involves stretching the relevant muscle through its entire ROM at a slow velocity (V1) and then a fast velocity (V3). The end angle during the V1 movement, or full passive ROM, is referred to as R2 and the angle of muscle reaction during the V3 movement is referred to as R1. The spasticity angle refers to the difference between R2 and R1, with a larger spasticity angle indicating a larger degree of velocity-dependent spasticity [6]. The larger this is the better the chances that the muscle will respond to botulinum toxin injections. If the difference between the two catch points is close to zero, that joint is likely contracted rather than spastic.

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The MTS has been found to have an overall acceptable inter-rater reliability, with about a 5-degree error window for PROM [7]. However, greater intra- and inter-rater variability was found when testing the R1 of the lower extremities, so caution should be used [8].

Hypertonia Assessment Tool The HAT is a 7-item instrument that discriminates spasticity, dystonia, and rigidity on 3 levels: item scores, subtype, and hypertonia diagnosis for each extremity. The HAT offers a rather well-­ described assessment tool to distinguish between hypertonia types in children with neuromotor disorders. For a detailed description of how to perform the HAT, please see the appendix.

 ral Medications for Spasticity O Management The first choice in a pharmacological approach in the treatment of spasticity is oral medications. Despite the general lack of information regarding the efficacy of these medications, they are the best conservative option. We will discuss the multiple options and the potential side effects in an attempt to aide in the prescribing of these medications for children and adults with spastic CP. You will need a good understanding of your patient and their goals in order to make the best decisions about optimizing medications (Table 3.1).

Baclofen The most widely used oral medication for the treatment of spasticity is baclofen. Baclofen is a GABAB agonist. Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter of the central nervous system and baclofen binds at the GABAB receptors, which results in hyperpolarization of the neurons [9]. It crosses the blood-­ brain barrier and binds to the GABAB receptors of laminae I–IV of the spinal cord which then inhibits the release of excitatory neurotransmitters and causes presynaptic inhibition of

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32 Table 3.1 Considerations for optimizing medication options Considerations for optimizing medication options Determine treatment goal for medication Reconcile patient medications and review potential drug interactions Ensure an appropriate drug formulation is available, i.e. tablet vs. liquid Start low and go slow with titrating medication dosing Regularly check labs for hepatotoxicity Wean appropriately to avoid rapid withdrawal symptoms and side effects Provide clear and concise written and verbal education to the caregiver and patient about the side effects and potential adverse symptoms as well as what to watch for

­ onosynaptic and polysynaptic spinal reflexes m [10]. Baclofen is available in oral and intrathecal formulations. In the oral formulation it is absorbed quickly with a half-life of about 3.5  hours and is partially metabolized by the liver but largely excreted by the kidneys, unchanged [11]. The short half-life leads to the necessity of repeated daily dosing to maintain a therapeutic effect. The principal side effect of oral baclofen is sedation. It is generally believed to be dose related and can be mitigated by starting treatment at a low dose and titrating upwards [9]. Other side effects include impairments of cognitive function such as confusion, memory and attention in addition to dizziness, weakness and ataxia [12]. Acute discontinuation of baclofen can cause signs and symptoms of withdrawal which can be quite severe and can potentially lead to death. It often includes a rebound increase in spasticity and can be coupled with spasms, hallucinations, and confusion [13]. It is important to understand that the patient should never suddenly stop the use of baclofen. Oral baclofen is not approved by the Food and Drug Administration (FDA) for the use in CP (it is approved only for spasticity in the setting of multiple sclerosis or other spinal cord lesions) but the off-label use is widely seen in the management of patients with CP.  Oral baclofen is not commercially available in a suspension formulation and must therefore be prescribed in tablet form. It can be crushed and put

into a liquid for use in a G-tube. There is no consensus on dosing but the typical starting dose is 2.5  mg/day with gradual titration. The maximum daily dose is based on weight (extrapolated from adult data) is 2  mg/kg/day for children over the age of 2 years [14]. Patient and caregiver education should include the necessity of weaning of the medication if they feel it is not effective. Abrupt withdrawal will result in the above-mentioned issues including rebound spasticity.

Tizanidine Tizanidine is another oral medication used in the management of CP spasticity. It can be used as an alternative medication or in conjunction with baclofen. It is an alpha-2 adrenergic agonist that prevents the release of excitatory amino acids resulting in decreased motor neuron excitability [11, 15]. Alpha-2 adrenergic agonists also have an anti-nociceptive effect, which may contribute to their tone-reducing abilities. Clonidine is an older version of an alpha-2 agonist but is better known for its effects on lowering blood pressure and heart rate and has been found to be more sedating than tizanidine [16]. Tizanidine has a half-life of about 2.5 hours and it is metabolized through the liver [17]. Similar to baclofen, the short half-life leads to the necessity of repeated daily dosing to maintain a therapeutic effect. The main side effect of tizanidine is sedation. Dry mouth and hepatotoxicity have also been reported [11, 17]. Safety and efficacy have not been established in children by the FDA, but similar to baclofen it is widely utilized for this off-­ label use. Tizanidine is available in an oral tablet (2- and 4-mg) formulation. To begin treating with tizanidine it is recommended that the dosing starts with half or quarter tablets as a single nighttime dose and gradually titrating upward and adding daytime doses as clinically indicated based on tolerance and effectiveness [11]. It is recommended that the medication be weaned when discontinuing to avoid rebound hypertension and hypertonia [18].

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Dantrolene Dantrolene sodium is a medication that works peripherally rather than through the central nervous system. It blocks the calcium release from the sarcoplasmic reticulum of skeletal muscle which leads to decreased contractility and subsequent spasticity [19]. It does not have an effect on cardiac or smooth muscle [20]. It is metabolized through the liver and eliminated in bile and urine. It has a half-life of 15 hours with peak blood levels 3–6 hours after ingestion [9]. Hepatotoxicity, lethargy, and fatigue are the main side effects. Liver function studies should be checked before starting dantrolene treatment and periodically throughout treatment. Since it effectively weakens the muscles, it can lead to a decrease in function for ambulators [16]. Dantrolene is approved by the FDA for children and adults with spasticity ages 5 and older. It is available in oral capsules, which can be opened and mixed with juice or water. The same principle of starting low with slow increased titration applies to this medication. The initial dose for children and adolescents is 0.5 mg/kg/dose twice daily with a maximum daily dose of 12/mg/day. The dose level should be maintained for 5–7 days before increasing it [11, 21].

Benzodiazepines Benzodiazepines work through GABAA receptors and are not direct agonists but rather cause a presynaptic inhibition through membrane hyperpolarization [22]. Benzodiazepines are metabolized by the liver and have a half-life ranging from 20–80  hours depending on the specific medication. Diazepam is the most commonly used benzodiazepine in the treatment of spasticity. It is rapidly absorbed by the body and reaches peak drug levels an hour after oral administration [9]. It is metabolized through the liver. Sedation is the most common side effect and it can affect the ability to increase the dose [23]. Prolonged use of diazepam can cause physical dependence and should never be discontinued suddenly or tapered too quickly [16, 23, 24]. Pediatric dosing of diaz-

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epam range from 0.12 to 0.8 mg/kg/day divided into three to four doses. This differs from the dosing used for acute seizures which ranges from 0.2 to 0.5  mg/kg rectally every 4  hours as needed. Diazepam is used commonly as an adjunct to other pain medications (opioids, acetaminophen and NSAIDs) following orthopedic surgery. It has been shown to be effective in reducing spasms associated with post-operative pain. Clonazepam is another benzodiazepine that is often used for nighttime spasms. It is quickly absorbed by the body and has a half-life of 18–28 hours [9, 11]. The usual starting dose for clonazepam is 0.5 mg but can be started lower to determine an effective dose.

Chemoneurolysis for Spasticity Management  verview of the Basic Concept O of Injections for Spasticity Chemical neurolysis has been a longstanding form of spasticity management, and is considered effective, safe, and minimally invasive [25, 26]. Direct injection with chemoneurolytic agents can be performed with either a botulinum toxin, or a chemical alcohol, such as phenol or ethanol [25, 27]. Both types of injection have their benefits and drawbacks, and consideration should be taken when performing injections for spasticity management. However, when used appropriately, injections can minimize the risk of systemic side effects associated with oral medications and intrathecal baclofen pumps, can allow for treatment of focal spasticity without causing diffuse weakness, and can decrease the need for multiple orthopedic surgeries. Because of these reasons, injections are one of the most common tools used for managing spasticity, and even other motor control disorders.

Botulinum Toxin Botulinum toxin is a neurotoxin produced by the bacteria Clostridium botulinum. The toxin blocks exocytosis of acetylcholine from the lower motor

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neuron at the presynaptic junction. This action is accomplished by cleaving one or more of the SNAP-25 (synaptosome-associated protein-25)/ SNARE (soluble N-ethylmaleimide–sensitive factor attachment protein receptor) proteins needed to accomplish the binding of acetylcholine vesicles to the intracellular membrane, thus blocking exocytosis. By effectively decreasing the quanta of acetylcholine released into the neuromuscular junction during an action potential, botulinum toxin limits the capacity for sarcomere depolarization to threshold, and the production of muscle fiber action potentials within a motor unit [26]. While ingestion of a food poisoned with botulinum toxin can produce a generalized flaccid paralysis, local injection of a limited dose of botulinum toxin can be used to weaken and decrease the tone of targeted muscles without overt systemic effects [25, 26]. For medical purposes, botulinum toxin is chemically produced by a number of pharmaceutical companies. While there are eight known variants of the toxin, types A through H, botulinum toxins A and B are most effective at producing weakness, and are the two types used for medical purposes. Botulinum toxin A is known to target the SNAP-25 protein, while botulinum toxin B targets synaptobrevin, a SNARE protein [26, 28]. Botulinum toxin A is marketed under brand names such as Botox, Dysport, and Xeomin. Botulinum toxin B is marketed as Myobloc [28]. Each formulation has its own relative strength and indications. In 2009 the FDA suggested standardization of the names of the available toxins to better identify and differentiate between the different formulations. Botox made by Allergan is now referred to as onabotulinumtoxinA, Dysport by Ipsen is abobotulinumtoxinA, and Xeomin by Merz is incobotulinumtoxinA. Myobloc manufactured by Solstice is now referred to as rimabotulinumtoxinB [29]. Injection of botulinum toxin has a limited period of efficacy. The denervating effects of botulinum toxin stimulate neuron terminal sprouting over time, creating new neuromuscular junctions. This reinnervation results in toxin effect lasting about 2–4 months. Frequent repeat

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injection with the same toxin is believed to result in decreased efficacy, secondary to antibody formation. Because of this, it is recommended that injections are repeated no more frequently than every three months [30, 31]. Most formulations of botulinum toxin require reconstitution of the powdered medication with a solvent, such as sterile normal saline. After injection, the medication is known to spread, and this spread is not limited by fascial planes, allowing the medication to spread from one muscle to the next [32, 33]. Because of this, it is worth considering the amount of dilution used for reconstitution, when preparing to inject botulinum toxin. In 2009, the FDA announced black-box warnings on labeling for botulinum toxin products, because of the risk of systemic spread of the toxin resulting in botulism poisoning-like symptoms. Symptoms of systemic spread include weakness, hoarseness of voice, dysarthria, bladder incontinence, respiratory distress, dysphagia, vision changes, and ptosis. Most of these events occurred in children with CP who received high doses of botulinum toxin to treat muscle spasticity. Severe cases resulted in hospitalizations and a few deaths [34]. In order to decrease the chances of adverse reactions, careful dosing strategies should be used. Dosing guides are available from the products’ manufacturers. Extreme caution should be taken when converting between different formulations of botulinum toxin. Units of one formulation are not equivalent to units of another formulation. For example, a typical dose of onabotulinumtoxinA is 100–300  units, whereas a typical dose for rimabotulimtoxinB is 5000– 15,000 units. No universally accepted conversion system has been developed [35, 36]. The most common toxin-associated adverse event is temporary weakness in the targeted or nearby muscles. However, when injected into the face or neck, this can increase risk of dysphagia or ptosis, depending on the site of injection. More systemic side effects can include generalized weakness, anaphylaxis, GI irritation, or flu-like symptoms, though these are much less common when an appropriate weight-based dosing of toxin is used [34]. It is also worth noting that

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needle introduction carries risks such as pain, bleeding/bruising, and soft tissue irritation or infection.

Alcohol Injections Chemical alcohols, such as phenol or ethanol, can be used as an alternative to, or in conjunction with, local botulinum toxins injections. Unlike botulinum toxin, chemical alcohols can be used to perform both focal intramuscular blocks with injections into the muscle, and total motor nerve blocks by injecting adjacent to a proximal motor nerve [27]. When used to target a proximal motor nerve, spasticity management can be provided to a larger group of muscles (all muscles distally innervated by the targeted nerve) with a small amount of medication. Most commonly, nerve blocks are provided to the obturator nerve for hip adductor spasticity, or the musculocutaneous nerve for elbow flexor spasticity, though other nerves can be targeted. In contrast, direct intramuscular blocks only affect the muscle into which the medication is injected. Denervation is accomplished via direct chemical denaturing and destruction of neuronal proteins via axonotmesis, rather than via chemical receptor blockade [27, 37, 38]. When delivered directly into the muscle, the medication works best when injected at “motor points,” points of the muscle belly where the largest number of synapses occur. Though maps of motor points of many muscles have been outlined, they are often best identified with the assistance of electrical stimulation, which is discussed later in this chapter [27, 37]. Either phenol or ethanol can be used for chemical alcohol denervation. Though choice of medication is generally determined by availability, phenol is believed to last slightly longer and diffuse less than ethanol. Alcohol injections generally last around 6 months and are cheaper than botulinum toxin injections [27]. Chemical alcohols also respect fascial planes, and are therefore less likely to spread between muscles. There is a significant (around 15%) risk of painful dysesthesias with chemical alcohol use. In the pediat-

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ric population, increased pain during injections may make phenol or ethanol injections less tolerated [39, 40]. Phenol can be packaged either as a crystalline solid, or in solution. When used for spasticity, phenol is usually diluted to around 3–12%. Ethanol is generally packaged as a solution and is diluted to 45–90% concentration [27, 39]. In general, a maximum dose of 30 mg/kg or 1 gram of phenol in a single treatment session) is recommended, though maximum volume will vary depending on dilution [39, 41]. Phenol is highly irritating to the skin, eyes, and mucous membranes in humans after acute (short-term) inhalation or dermal exposures. Phenol is considered to be quite toxic to humans via oral exposure. The Environmental Protection Agency has classified phenol as a Group D substance, not classifiable as to human carcinogenicity. Chemical alcohols share similar risks to botulinum toxin in regards to needle introduction. Excessive weakness can also occur if too much medication is injected. As discussed above, chemical alcohols also have increased risk of painful dysesthesias. If medication is injected into or adjacent to nerves with sensory fibers, there is a risk for numbness along with dysesthesias. Systemic side effects, which are associated with large volume injections, include generalized weakness, muscle tremors, changes in arousal, and cardio-respiratory suppression [39].

Technical Considerations Injections for spasticity can be performed blind using anatomic landmarks for guidance, or with the assistance of electrical stimulation, and/or ultrasound. There is strong, Level 1 evidence to support the superiority of instrumented guidance for botulinum toxin injections with both assistive modalities [42, 43]. Electrical stimulator guidance uses a pulsed electrical charge delivered into the muscle belly via an electro-conductive needle attached to the syringe with medication. At an appropriate voltage, the electrical stimulator produces a rhythmic twitch response of the muscle that can be both vis-

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ibly appreciated, and identified via palpation of the muscle or tendon [27, 39]. An understanding of anatomy and muscle function allows the injector to therefore identify when the needle is located within the desired muscle belly. Twitch response is maximized when the needle tip is located near the motor point, making electrical stimulation a very useful tool in optimizing response to chemical alcohol injections [27, 39]. However, this electrical stimulus may be perceived by a patient as uncomfortable or even painful, especially at higher voltages. Furthermore, repeat needle redirection for localizing the motor point may prolong the time the needle is within the target. It should also be noted that excessive voltage can result in spread of the stimulus, innervating multiple muscles simultaneously. If the needle is located adjacent to a motor nerve, all muscles innervated by the nerve may be stimulated. Ultrasound uses sonar wave refraction to develop an image of tissues directly below the skin. Though there is a steep learning curve for effectively using ultrasound guidance, the modality allows for adjustable real-time evaluation of skeletal muscles, and can be used to guide the placement of a needle tip into its desired target. Though ultrasound does not allow for identification of motor points in the same way electrical stimulation does, it does allow for visual confirmation of needle tip location, and can be less uncomfortable for a patient [42, 43]. Ultimately, the decision to use guidance should be informed by equipment availability, patient’s ability to sit still and tolerate discomfort, the muscles targeted, and injector’s training level with each modality. It should also be noted that both electrical stimulation and ultrasound can be used in conjunction when desired, though use of guidance may prolong the length of procedure.

I mproving Patient Tolerance During Procedure It is well recognized that many developmentally normal children have a phobia of needles, and oftentimes children will have to sit through multiple injections to their muscles during a single

procedure for spasticity. Furthermore, discomfort may be exacerbated by the use of electrical stimulation, or the injection of chemical alcohols. The patient’s capacity to sit still may further be complicated by any cognitive or emotional developmental delays associated with the cause of their spasticity. Depending on the resources available to the physician, there are multiple modalities by which a patient’s tolerance of the procedure can be improved. Multiple topical analgesics may be available to the patient prior to injections. Use of cold spray with ethyl chloride before injection is a common tool for improving injection tolerance, though some patients find the actual cold produced by the spray to be difficult to tolerate. Alternatively, a lidocaine cream, or similar topical solution, can be applied directly over the sites of injection [44, 45]. A limited number of studies have looked into various forms of distraction for patients to improve tolerance to procedures, which can range from playing music to the use of virtual reality headsets [46, 47]. However, an alternative, if available and if a patient is unable to tolerate the procedure despite the use of the above pain-relieving modalities, would be to perform injections under general anesthesia or conscious sedation. The use of anesthesia or sedation requires the appropriate procedural setting and associated physicians and staff. If available, general anesthesia allows a patient to receive appropriate injection based spasticity management when they otherwise would not be able to.

Patient Selection In the spectrum of treatments for spasticity, injection based therapies are most ideal for patients with focal spasticity, and can be used ­independently from, or in conjunction to other modalities such as oral medications or baclofen pumps. As discussed above, both botulinum toxin and chemical alcohol treatments have a maximum weight-­based dose which limits the number of muscles that can be effectively targeted. As the medication is applied locally in injections, this

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procedure provides less global spasticity coverage compared to oral medications, but also minimizes the systemic side effects. Therefore, an ideal candidate for injection based spasticity management has a limited number of muscles or joints that can be targeted to significantly improve pain, functional independence, ambulation, or caregiver burden [25–27]. As discussed above, the effect of botulinum toxin generally lasts around 3–4  months, while chemical alcohol-based injections generally last around 6 months or more. Current recommendations to minimize the potential for development of neutralizing antibodies include using an injection schedule that separates injections at a minimum of 3  months, using the lowest effective dosage, and avoiding booster injections, which are injections given in the interval between the every-3-months injection schedule [36]. Consideration should also be given as to whether the patient will be able to come for appointments every 3–4 months for injection and follow-up. Patient age and development should also be taken into consideration when planning injections. There is limited data showing that injections at an age younger than 5 improves injection efficacy for managing plantar flexion tone in patients with CP [48]. During growth spurts, spastic muscles become tighter as muscle growth follows bone growth [49]. Therefore, it may be advantageous to be more aggressive when a patient is undergoing growth spurts, or is expected to in the near future based upon age.

Single-Event Multilevel Chemoneurolysis The single-event multilevel chemoneurolysis (SEMLC) approach has been developed to manage multilevel spasticity rather than focal spasticity by using botulinum toxin and chemical agents such as phenol or alcohol. Use of SEMLC allows for more muscles to be targeted during a single procedure, without using greater than the maximum dose of either medication, while still avoiding the more systemic side effects associated with treatments such as oral medications or intra-

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thecal baclofen. Studies have shown no significant increased risk of side effects associated with SEMLC, compared to injections with just one medication. SEMLC can therefore be used to provide injection based spasticity management in patients with more generalized increased tone, as it has been shown to be relatively non-inferior and without increased risk [50–52].

Intrathecal Baclofen Therapy Intrathecal baclofen (ITB) therapy is used to treat pediatric and adult patients with severe spasticity and to a more limited extent, patients with dystonia. Debilitating spasticity and secondary dystonia are associated conditions not uncommon in childhood-onset neuromuscular conditions such as CP.  Spasticity is the most common form of hypertonia of cerebral origin seen in children with CP [53–58] and can also be a significant problem in spinal cord and traumatic brain injury [59]. Spasticity is a velocity-dependent resistance to muscle stretch that occurs when “resistance (to external movement) increases with increasing speed of stretch and/or resistance (to externally imposed movement) rises rapidly above a threshold speed or joint angle” [60]. A signal imbalance between the nervous system and the muscles thus produce increased muscle activity. Dystonia, on the other hand, is characterized by involuntary muscle contractions that cause repetitive movements and twisted postures [61]. Penn and Kroin [62] were the first to use the ITB pump to treat spasticity of spinal origin, and in 1985 Dralle and colleagues described a case report of a 4-year-old child with history of near-­ drowning whose spasticity improved after continuous ITB infusion. In 1991, Albright and colleagues [63] first described the ITB pump use in children with spasticity associated with CP.  The Food and Drug Administration (FDA) approved the ITB pump for spasticity of spinal origin in 1992 and cerebral origin in 1996. At the time of approval, there were fewer than 200 children with implanted pumps [64]. In the last three decades, ITB therapy has been documented as an effective and reliable treatment

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of severe spasticity [65–72]. A multicenter US clinical trial confirmed the efficacy and relative safety of ITB therapy in both children and adults [73]. A consensus of clinician experts in Europe recommended ITB therapy in children with CP, Gross Motor Function Classification System (GMFCS) levels IV and V where spasticity interferes with patient’s activities and/or quality of life [74]. However, a Cochrane Review by Hasnat and Rice [75] reported that the small sample sizes and methodological issues of the appraised studies limited the validity of evidence for ITB effectiveness in children with CP.  The American Academy for Cerebral Palsy and Developmental Medicine’s systematic review of the literature on ITB as spasticity treatment in CP concluded limited evidence in spasticity reduction in the lower extremities, unclear effect on spasticity in the upper extremities, improvement in function and ease of care, and manageable complications [76]. ITB therapy decreases, but does not eradicate, spasticity or dystonia. It often helps patients to achieve higher function, reduce the risk of joint contractures, decrease spasticity-associated pain, and facilitate ease of patient care.

Pharmacology and Mechanism of Action In 1962, Swiss chemist Heinrich Keberle first synthesized oral baclofen which was marketed as an antiepileptic in 1972, but it did not prove to be effective [77]. Oral baclofen was observed to help improve spasticity and subsequently was used for this purpose. Briefly, baclofen is a synthetic structural analog of gamma-aminobutyric acid (GABA) agonist acting on GABA-B receptors in the spinal cord to reduce abnormal muscle tone. The precise mechanism of its action as a muscle relaxant and an anti-spasticity medication is still not fully understood. Baclofen inhibits both monosynaptic and polysynaptic reflexes at the spinal level, possibly by decreasing excitatory neurotransmitter release from primary afferent terminals. Spasticity is then controlled by the reduction of the hyperactivity in

this monosynaptic reflex arc at the level of the spinal cord. Actions at supraspinal sites may also occur and contribute to its clinical effect [54]. Through a similar mechanism, baclofen inhibits excessively stimulated supplementary tracts and the motor cortex to improve dystonia [78]. In one study, in seven patients who received a 50–100 mcg intrathecal Lioresal (baclofen) bolus, the average cerebrospinal fluid (CSF) elimination half-life was 1.51 hours over the first 4 hours and the average CSF clearance was approximately 30 mL/hour [79].

 hat Is the Difference Between Oral W and Intrathecal Baclofen? Oral baclofen has limited lipid solubility and therefore crosses the blood-brain barrier poorly. Its effects are spread widely in the central nervous system but cannot achieve adequate therapeutic concentration in the CSF. This often leads to adverse effects including sedation, nausea, dizziness, confusion, weakness, and hypotension [23, 80]. Conversely, ITB pump delivers the baclofen near its site of action around the spinal cord in the subarachnoid CSF space. This allows for an intrathecal dose less than 1% of the oral baclofen dose, thus almost eliminating the incidence of adverse systemic effects [23, 81]. ITB therapy is recommended when high dose of oral baclofen does not adequately control spasticity or low dose of oral baclofen produces ill side effects i.e., lethargy, fatigue, hypotonia.

Patient Selection Intrathecal baclofen is FDA-approved for the management of severe spasticity of cerebral ­origin in pediatric patients at least 4 years of age and large enough to accommodate the implanted pump. Ideally, patient selection is facilitated in a multidisciplinary clinic staffed by but not limited to pediatric orthopedist, neurologist, neurosurgeon, physiatrist, nurse practitioner or physician assistant, physical and occupational therapists, social worker, and nursing. The multidisciplinary

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clinic should also provide access to a full range of tone management options including oral medications, chemodenervation or neurolysis, selective dorsal rhizotomy (SDR), deep brain stimulation (DBS), and orthopedic procedures. Intrathecal baclofen therapy can be used as a monotherapy or in combination with other spasticity-­ reduction methods and not limited only to patients who have failed conservative or invasive approaches [82–84]. Intrathecal baclofen therapy combined with rehabilitation can be effective in certain ambulatory patients with CP when gait and lower extremity movements are inhibited by spasticity [63, 64]. Prior to initiating ITB therapy for a patient, contraindications and other medical comorbidities should be considered. Intratehecal baclofen is contraindicated in patients with hypersensitivity to baclofen, which is rare, or active infection [84]. Some patients with an adverse reaction to baclofen may be mistakenly classified as having an allergic reaction. Clinicians need to accurately identify those with a true baclofen allergy so as to avoid eliminating a potential ITB-benefiting candidate. Increased risk of seizures has been associated with ITB therapy in patients with multiple sclerosis and traumatic brain injury [85–87]. In contrast, Albright and colleagues [65], Buonaguro and colleagues [88] and Kofler and company [89] all reported ITB does not seem to exacerbate or induce seizure activity in children with spasticity of cerebral origin. The effect of the ITB on the progression of scoliosis remains controversial [90, 91], while Senaran and colleagues’ study in 2007 demonstrated that ITB has no significant effect on curve progression, pelvic obliquity, or the incidence of scoliosis when compared with an age, gender, and GMFCS score-matched control group of patients with spastic CP without ITB [92]. Similarly, Rushton’s group in 2017 reported ITB pump does not appear to alter the natural history of curve progression in this population. Patients with a gastronomy tube, suprapubic cystostomy, and spinal fusion are not considered a contraindication for a pump, but require a pre-­ ITB surgical planning [84]. Similarly, vascular

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shunting for hydrocephalus is not a contraindication, but concurrent use may affect cerebrospinal fluid flow [93, 94]. Relative contraindications include unrealistic goals and expectations, mental health issues, psychosocial factors affecting compliance, obesity, cachexia, and financial burden [84].

ITB Trial Intrathecal baclofen trial is a screening test performed before implanting the ITB pump. This is a recommended best practice to evaluate patient’s response to a typical one-time dose of ITB delivered via a lumbar puncture [84]. During the trial, the patient is evaluated before and then after the ITB injection over a 4- to 6-hour period. If a patient has a satisfactory reduction in tone, ITB pump therapy is recommended. As an alternative to this single ITB bolus trial, Pucks-Faes and colleagues [95] recently described a 6-day (median duration) in-patient continuous ITB trial which has the major advantages of offering comprehensive evaluation of function and systemic effects over time. In a recent survey, nearly 70% of the clinicians managing ITB pumps always or often used a screening test [84]. At some institutions, ITB screening trials are strongly recommended only for ambulatory patients and often performed with gait laboratory analysis concurrently to assist in the decision-making process [64]. Conversely, others endorse the omission of ITB trialing to reduce the complications associated with it [74]. In addition, the trial has been reported to provide no reliable indication to predict long-term therapeutic outcomes [84].

 urgical Implantation of Intrathecal S Baclofen Pump To date, the SynchroMed II intrathecal pump for pediatric patients is the only commercially available implantable pump whose rate of infusion is adjustable, allowing for modulation to meet an individual’s tone management. The round pump

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has two sizes and volume capacities: 20-mL (0.78 inch thick, 165 grams when empty) and 40-mL (1 inch thick, 175 grams when empty) with 4–7 years of battery life and weigh 185 grams and 215 grams, respectively, when full. This pump is designed to be safe under certain conditions for patients who may require an MRI scan and compatible with many other diagnostic tests [96]. Under general anesthesia, the battery-powered intrathecal pump is implanted either subcutaneously or sub-fascially in the lateral abdominal wall. One end of the intrathecal catheter is inserted into the intrathecal space, the catheter is tunneled along the lateral side of the trunk subcutaneously and the other end is attached to the pump. The reported advantages to the sub-fascial placement are reduced incisional tension, less pump bulging, and a potential decrease in complications [63, 74, 97, 98]. The spinal level of the intrathecal catheter placement varies depending on the therapeutic goals. As suggested by Aljuboori and team [99], Albright and colleagues [100], and Dan and associates 9740, optimal intrathecal catheter placement are as follows: approximately at the level of T10–T12 for spastic diplegia, C5–T2 for spastic quadriplegia; and C1–C4 for general dystonia. On the other hand, placing the ITB pump catheter tip in the upper spine could potentially lead to an increased incidence of central side effects by increasing the supraspinal concentration of baclofen in the cerebrospinal fluid [101].

ITB Pump Management The pump is initially programmed in the operating room by a computer. Typically, all subsequent ITB pump managements, including programming changes, are performed in an out-patient setting. Two types of ITB infusions are available: (a) constant daily rate (simple continuous mode) and (b) variable rate (flexible dose mode), which permits individualized dosing fluctuations, including boluses, to address the times during day/night when the patient is most spastic.

The ITB pump is programmed using a computer and the handheld radiowave-mediated controller, which is placed over the pump site. Under sterile techniques, the pump reservoir is filled by direct injection through the overlying skin. Frequency of ITB pump refills range from approximately every 4  weeks to 6 months depending on the daily dose and concentration. Three intrathecal baclofen concentrations, 500 mcg/mL, 1000 mcg/mL, and 2000 mcg/mL are available. Typically, the baclofen 500 mcg/mL concentration is initially used when the pump is implanted in the operating room. As the baclofen daily dose increases, changing to the higher concentration reduces the frequency of pump refills. The patient’s weight and level of spasticity are unrelated to ITB pump dosing. Individualized dose optimization is achieved through multiple clinic visits until therapeutic goals are met. At each visit, the clinician must perform a focused history and physical exam to evaluate current spasticity status to determine if ITB dose should be increased, decreased, or maintained. Equally important, the clinician must be cognizant of potential side effects from previous ITB dose adjustments, drug-to-drug interactions, examination of ITB pump and catheter incision sites, and any change in medical status. Paramount to improving clinical outcomes of patients with ITB pump is the involvement in a comprehensive tone management program dedicated to providing ITB therapy, attended by expert clinicians who are experienced in this spasticity treatment.

Complications Complications, although rare, can be related to the pump delivery system or the medication dosing. When suspecting a problem, trouble-­shooting involves multiple procedures (such as x-ray, catheter access port procedure , dye study, and/or nuclear scan) to evaluate the integrity of the pump and the delivery system. All possible causes must be entertained during evaluation of suspected ITB complication. For example,

3  Spasticity Management: Nonoperative and Operative

ITB withdrawal syndrome can be nonspecific on presentation and can mimic other illnesses, especially in the medically complex patients. This includes, but is not limited to, constipation, urinary tract infection (UTI), gastroesophageal reflux (GERD), UTI, pneumonia, or any source of pain that can cause increased tone even if the patient is at a previously optimized ITB pump dose.

Overdose Intrathecal baclofen overdose has been related to pump malfunction and most commonly caused by human error such as when a computer programming step is missed during drug concentration change, or unintentional excessive dose infusion during dose adjustment or catheter test occurs. Overdose is characterized by lethargy symptoms progressing to unresponsiveness and hypotonia and possibly coma. Overdose is typically managed in an intensive care or monitored unit to monitor for the potential need for ventilator assistance. Unfortunately, no direct pharmacologic antagonist or antidote for treating baclofen overdose is currently available. Withdrawal Intrathecal baclofen withdrawal syndrome occurs when the intrathecal delivery of baclofen is abruptly interrupted or stopped. Severity of this syndrome is unrelated to dose and can present within a few to 48  hours varying in degree of intensity [84, 102–104]. Reported withdrawal signs and symptoms include recurrence or worsening of baseline spasticity associated with itching without rashes, diaphoresis, fever, hallucinations, and/or autonomic dysreflexia. If patient is nonverbal, typically caregivers report recurrence of baseline spasticity without relief and the patient’s appearance of “something is wrong.” Oral baclofen and benzodiazepines must be administered immediately and the patient must be taken to the emergency room for evaluation and treatment. Typically, these patients are managed in intensive care unit due to potential for rhabdomyolysis and multiorgan failure.

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Motta and Antonello [98] reviewed 430 patients with ITB pump at a single center and found at least one complication occurred in 25% of these patients requiring surgical intervention: infection in 9.3%, CSF leak in 4.9%, catheter problem in 15.1%, and pump problem in 1%. Further, Stewart and colleagues [105] reported that these results were “consistent with others reported in the literature with 25% of patients with ITB experiencing major complications.”

Infection The reported incidence in the literature is anywhere from 0% to 25% [54, 82, 106, 107] which usually requires removal. Risk of late infection over 5  years post-implant was 0.95% per year reported by Bayham and colleagues [106]. Catheter Issues In 2011, Medtronic introduced a new catheter with a multilayer design. Motta and colleagues [108] observed a reduction in catheter complications with this new catheter design. Spine surgeons must be cognizant of the potential unintentional catheter disruption during spinal fusion. In this case, ITB withdrawal symptoms can be mistakenly attributed to post-op recovery, pain, or medications [109–111]. Moreover, Caird’s retrospective study in 2007 reported that patients with CP and implanted ITB pumps who underwent spinal fusion have more complications compared with similar patients with CP but without ITB pumps [112]. Pump-Related Issues Gooch and colleagues [113] reported the minimum number of days following post-ITB pump implant until detection of the first device-related complication was 7  days, but maximum was 807 days and the average was 262 days.

Patient/Family/Caregiver Education The best outcomes are dependent on clinicians’ expertise and a thorough education of patient and caregivers before and during ITB therapy. Education enables patients and caregivers to

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become active participants in the treatment process especially when preventing serious complications of ITB therapy [109]. A full understanding of the plan of care, treatment goals, and patient and family responsibilities leads to improved communication [109, 114]. It is essential for patients and caregivers to recognize ITB therapy as a part of comprehensive spasticity management. Consistent participation in rehabilitation therapy, home exercise program, brace wear, and clinical surveillance by other subspecialists including pediatric orthopedist, neurologist, and physiatrist are needed to optimize the effectiveness of ITB therapy. The following are education highlights that need to be addressed when a patient is indicated for ITB therapy and throughout the duration of treatment: • Significance of adherence to therapy • Emphasis on the unique roles of multidisciplinary ITB therapy members • Potential side effects and complications • Multiple clinic appointments with dose adjustments (early phase of treatment) and refills • Missed appointments for pump refill which can lead to withdrawal syndrome • Accessible emergency oral baclofen tablets at all times • Potential life-threatening withdrawal and overdose including “what to do” plus emergency card with contact names, phone numbers • Travel and leisure emergency procedure planning • Review of baseline spasticity pre-ITB pump, and functional gains post-ITB therapy • Prior to any diagnostic tests, notify physician or healthcare providers of the implanted ITB pump • Following an MRI test, the pump must be checked to confirm if working properly • Timing of pump battery replacement • ITB dose weaning and pump explanation option • Troubleshooting techniques • Transition of care (from pediatric- to adult-­ based healthcare services)

 elective Dorsal Rhizotomy S for the Treatment of Spasticity Introduction Selective dorsal rhizotomy (SDR) is a neurosurgical procedure performed on the lower spine that has been demonstrated to reduce spasticity, increase range of motion, improve gross motor function and gait, and decrease the rate of subsequent orthopedic surgery in children with CP. Of all the neurosurgical procedures and orthopedic procedures currently used for the management of CP, SDR has undergone the most rigorous scientific study. In recent years, there have been significant advances in both medical and surgical treatment of CP spasticity, but permanent reduction of spasticity can only be achieved with SDR.

History and Pathophysiology Originally derived from late nineteenth century procedures for spasticity during which a complete nerve root transection was performed, modern-­ day SDR uses electric stimulation of dorsal sensory rootlets to activate the hyperactive reflex arc at the spinal cord and guide selective lesioning of the most spastic nerve fibers [115]. The ability of SDR to reduce spasticity can be explained by the pathophysiology of spasticity. Motor control and tone of the muscle is ultimately controlled by the alpha motor neuron in the spinal cord. Interneurons within the spinal cord gray matter have a regulatory influence on the activity of the alpha motor neuron. These interneurons generally have an inhibitory effect on the alpha motor neuron and are activated by descending input from cortical upper motor neurons. On the other hand, interneurons are inhibited by the local spinal reflex arc, which are mediated by IA sensory fibers. With damage to the brain or spinal cord, the balance of input is disrupted, and the reflex arc becomes hyperactive, leading to increased limb tone and spasticity. By selectively lesioning sensory nerve rootlets, SDR reduces the amount of IA sensory input and helps restore a more normal balance to the alpha motor neuron.

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Indications and Contraindications Although indications for SDR vary among medical centers, there is general agreement that the best candidates for SDR are children with normal intelligence between 2 and 8 years of age with a history of premature birth and a pure spastic diplegia (e.g. good underlying strength, minimal contractures, and postural stability). Importantly, however, many other patients have been shown to benefit from SDR including children with spastic quadriparesis [116] and hemiplegia [117], and higher functioning adults [118]. Importantly, SDR will not resolve already established orthopedic issues such as contractures, joint subluxation, dislocation, or bony deformity. Early reduction in tone has been shown to reduce the development of orthopedic issues and, thus, operations to reduce tone should be considered prior to the onset or surgical treatment of orthopedic problems when possible [119, 120]. Contraindications for SDR typically include patients with a history of severe central nervous system infection, hypoxic encephalopathy, progressive neurological disorder, severe basal ganglia damage, and mixed hypertonic CP with predominant dystonia, ataxia, or rigidity.

Fig. 3.1  Intraoperative photograph during SDR surgery. The dorsal roots from L1–S1 are wrapped in the blue silastic sheet to separate them from the ventral roots and sphincter roots. Rhizotomy probes are seen stimulating an exiting ventral root prior to exiting the neural foramen in order to establish the neurophysiologic stimulation threshold for motor vs. sensory roots

using electrical stimulation and neurophysiological monitoring (Fig. 3.1). Ventral roots are separated from dorsal roots and each dorsal root is separated into 4–8 rootlets. Individual dorsal rootlets are then stimulated to determine which should be transected based on the relative severity of the spasticity elicited. Stimulated sensory rootlets that demonstrate sphincter innervation or normal responses are preserved, while rootlets Surgical Technique demonstrating spastic responses when stimulated are transected. Intraoperative palpation of muscle General anesthesia is administered but long-­ groups during rootlet stimulation by a physical acting muscle relaxants and propofol are avoided and occupational therapy team or physiatrist is to prevent any effects on neurophysiological helpful in providing physiological feedback monitoring. Patients are positioned prone on a when determining which rootlets to transect suitable frame or bolsters. Electromyography based on the degree of spasticity elicited. With (EMG) needles are then placed in the major the single-level laminectomy surgical approach, lower extremity muscle groups (hip adductors, ventral roots are easily identified via electrophysquadriceps, tibialis anterior, hamstring, and gas- iological stimulation [122]. Many centers pertrocnemius) and sphincter muscles. Although this form transection of 40% or less of rootlets due to procedure is often performed with a five-level concerns such as iatrogenic neurological deficits laminectomy or laminoplasty to expose the roots [123–127]. However, other centers including as they exit the spinal canal, we prefer the SDR ours support aggressively transecting up to 70% through a single laminectomy [121]. A single-­ of rootlets based on data suggesting that relief of level laminectomy at the L1 level is performed, spasticity is proportional to the percent of dorsal and access to the conus-cauda equina junction is nerve tissue transected [115, 125, 128]. confirmed via ultrasound prior to opening the Recovery from surgery typically takes dura [121]. Nerve roots are isolated and tested 2–3  days, followed by discharge to home with

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intensive outpatient rehabilitation or to acute inpatient rehabilitation. Long-term physical and occupational therapy is critical to insure optimal outcomes.

Outcomes There have been many excellent long-term outcome studies for SDR. The outcome measures examined include muscle tone, flexibility, gait pattern, functional positioning, and the ability of the child to deal with his or her environment. Nearly all studies investigating SDR have demonstrated a significant and persistent decrease in spasticity without a return of hypertonicity over time. Improved function and ambulation are commonly seen regardless of the preoperative abilities [116, 129, 130]. After SDR, 50–78% of patients with impaired ambulation have been found to improve to a higher level of independence (e.g. walk with assistance to walk with walker alone) [131]. More recently, long-­term outcome data for children with spastic diplegia who underwent SDR in Cape Town have been published [130]. In this prospective cohort study, the data demonstrate that significant improvements in both range of motion and quality of gait (cadence and step length) persisted over a 20-year period. Importantly, SDR did not abolish the need for subsequent orthopedic surgery, as approximately half of these children still required lengthening of the rectus femoris, hamstrings, and/or Achilles tendon. McLaughlin et al. reported a comparative analysis and meta-analysis of three randomized clinical trials in 2002 [125, 126]. Eighty-two children with spastic diplegia received either SDR and physiotherapy or physiotherapy alone. Outcome measures were used for spasticity (Ashworth scale) and function (Gross Motor Function Measure) and applied at a 1-year follow-­up visit. Overall, selective dorsal rhizotomy with physical therapy was more effective than physical therapy alone in reducing spasticity and improving overall function in children with spastic diplegia. SDR has typically been more commonly recommended for children with spastic diplegia due

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to the unpredictable effects of SDR on the upper extremities. However, numerous examples of spasticity reduction and functional improvement in the upper extremities have now been reported in patients with spastic quadriplegia undergoing SDR [128, 132–135]. For instance, Gigante et al. [128] demonstrated that over 90% of patients with upper extremity spasticity had a reduction in tone and over 70% had an increase in motor control or spontaneous movement of the upper extremities after SDR. The specific mechanisms responsible for these suprasegmental effects are not known. Historically, SDR was only performed to manage spasticity in children. However, increasing evidence suggests that older adolescents and adults can benefit from SDR as well. In the largest series of adult patients undergoing SDR to date, patients after surgery had a reduction in spasticity, improved joint ROM, and improved function [119]. The best results were seen in adults who were already independent ambulators. Although many studies have documented the efficacy of both SDR and intrathecal baclofen therapy on the treatment of spasticity, very few papers compare these treatments directly [116]. In a landmark paper, Kan and colleagues [116] reported a consecutive series of 71 children who underwent SDR for spasticity and compared them with another group of 71 children who underwent ITB therapy matched by age and preoperative score on the gross motor function classification system (GMFCS). At 1 year postoperatively, both SDR and ITB therapy decreased tone, increased passive range of motion (PROM), and improved function. Compared with ITB therapy, however, SDR provided a dramatically larger magnitude of improvement in tone, PROM, and gross motor function. In addition, fewer patients in the SDR group required subsequent orthopedic procedures (19.1% vs. 40.8%). Spasticity reduction after SDR is seen immediately. Functional gains, however, require intensive strengthening and rehabilitation and typically continue to improve over the first year postoperatively. Any subsequent orthopedic procedures are generally deferred until at least 6–12 months

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after SDR in order to give adequate time for patients to get to a new functional baseline and more accurately determine if orthopedic intervention is required.

Complications Selective dorsal rhizotomy is a well-tolerated procedure with a very low risk of permanent morbidity. The most common complications seen following SDR include pain or transient neurologic dysfunction such as weakness, sensory loss, or bladder dysfunction. The majority of these are temporary, with permanent dysfunction occurring in less than 5% of patients [136]. An even smaller percentage of patients have any type of functional decline after SDR SDR does not eliminate the need for future orthopedic surgery. Approximately 34% of patients who are operated on between the ages of 2–5 years may ultimately still require surgery for orthopedic complications within 7.5  years after SDR [137, 138]. However, this is in contrast to the approximately 60% of patients with spasticity at birth, who without SDR will require an orthopedic procedure by the age of 8 [137, 139]. Studies following children 20–30  years after SDR have documented that between 50% and 60% will eventually undergo orthopedic surgery [140]. The relationship between SDR and spinal deformity is difficult to determine because the risk of scoliosis is increased among children with CP independent of SDR.  Although reports of progressive spinal deformity and spinal stenosis after SDR have been published [141], these are primarily among patients undergoing multilevel laminectomy or laminoplasty (L1–S1) for SDR. In the new era of SDR through limited laminectomy (L1 only), the risks of progressive spinal deformity after SDR are reduced. A recent large study demonstrated that nearly 10% of children after SDR will require spinal deformity surgery, but there was no evidence that SDR contributed to the progression of spinal deformity [142]. Long-term radiographic follow-up is generally not needed unless clinical signs of scoliosis develop.

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Combined Dorsal-Ventral Rhizotomy Perhaps the most difficult patients to manage clinically are those with severe mixed spasticity and dystonia. SDR alone is not typically recommended for these patients because it results in a reduction of the spasticity without addressing the dystonia. Although these patients are typically managed with a combination of nonoperative therapies or intrathecal baclofen therapy, in some cases the overall treatment will be unsatisfactory. Recently, clinical outcomes have been reported for children with CP who underwent combined selective dorsal and ventral rhizotomy (SDR/VR) for treatment of severe mixed dystonia and spasticity [143]. In this prospective study, 50 children with moderate to severe mixed hypertonia underwent SDR/VR through a L1–S1 laminoplasty with intraoperative neuromonitoring and intensive postoperative rehabilitation therapy. Muscle tone (modified Ashworth scores), dystonia (Barry-Albright dystonia scale), and joint range of motion were evaluated preoperatively and at 2, 6, and 12 months postoperatively. At 12 months postoperatively, patients had reduced tone (mean 3.54 vs. 2.0; p 4) [74, 77], although this may not be possible in young patients with small epiphyses. Internal/external/flexion and extension view of the hip are used to confirm appropriate screw placement. The wound is irrigated, hemostasis achieved and closed in the routine layered fashion. Sterile dressing of surgeon’s choice is applied to cover the incision.

Surgical Technique

Aftercare/Rehab

Ensure appropriate AP and lateral views can be obtained prior to draping. The guidewire is placed along the skin of the anterior hip in the intended path, checked with fluoroscopy, and a 1-2 cm skin incision is made on the lateral thigh, directly lateral. The fascia is incised sharply, and blunt dissection down to bone is performed. The wire start point is identified on AP and lateral views, and then advanced to the inferior quadrant of the head under fluoroscopic guidance. An arthrogram can be used to visualize unossified portions of the femoral head and guide placement of the screw into the epiphysis without breaching

Rehabilitation is guided by additional concurrent procedures, but if performed in isolation, the patient may weight-bear immediately as tolerated, with assistive devices for comfort. Range of motion, strengthening, and functional exercises can begin immediately as tolerated.

Outcomes In a series of 28 patients with CP who were GMFCS levels 3–5 and underwent guided growth of the inferior proximal femoral physis in

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56 hips, the majority demonstrated improvement in migration potential [74]. The most common complication involved the epiphysis growing off the screw tip which occurred in 9 patients. The screw was successfully exchanged in 5 patients, the screw head broke during one attempted screw exchange, 4 hips were treated with a second parallel screw insertion, and 3 hips went on to require reconstructions/osteotomies.

Proximal Femoral Osteotomy Indications and Planning Patients with CP typically have coxa valga and increased femoral anteversion. Therefore, optimal correction is obtained through a varus derotational osteotomy (VDRO). Other deformities such as caput valga, coxa vara, and femoral retroversion are possible, and proximal femoral osteotomy correction can be tailored to a patient’s specific deformity. Coxa valga and femoral anteversion lead to an intoed gait with lateral hip subluxation. Physical exam should be used to determine internal and external rotation at the hip. A reasonable guide to correcting version involves measuring the difference between internal and external rotation, divide by 2 and derotate by that amount (e.g., a patient has 80 degrees of internal rotation and 30 degrees of external rotation, with a difference of 50°, thus derotate by 25°). Craig’s test can also be used to approximate femoral anteversion; 10–15° of femoral anteversion is considered normal, so if Craig’s test estimates 45° anteversion, derotate by 30–35°. Alternatively, the amount of deviation from normal on the gait analysis can be used to guide the appropriate amount of derotation required (if there is 20° of excess hip internal rotation on gait analysis, derotate by 20°). If there is a large mismatch between physical exam findings and gait analysis, CT version study may be an additional useful data point. Femoral derotation for lever arm dysfunction is discussed more in depth later in this chapter and tibia derotation in Chap. 7. VDRO can be performed prone, yet the author’s preferred position is supine due to famil-

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iarity with this anatomic position, ease for the anesthetist, and ability to perform concurrent procedures such as adductor lengthening, pelvic osteotomy and patellar procedures. Proponents of prone position cite ease of using the leg as a goniometer to dial in the correct degree of derotation (Fig. 6.13). The favored implant for fixing a proximal femoral osteotomy in children with CP is a blade plate. A plate is a fixed angle device making it less likely to fail in osteopenic bone. Further, it may allow earlier weight-bearing than a nonfixed implant which is beneficial to minimizing bed rest in children with CP.  Fixation with a blade plate can be a technically difficult procedure particularly in soft bone with severe deformity. It is not uncommon for the blade to back out during implantation, to follow a path other than the one made by the chisel, or for it to “windshield wipe” out of the chiseled path while reducing the shaft to the plate. Multiple vendors now supply a cannulated pediatric plate system, which has greatly improved the ease of this procedure as it helps to maintain the path of the chisel while it is being exchanged for the plate, as the blade following the wrong path is common in soft bone. Most blade plates come in infant, child, adolescent, and adult sizes, and proximal femoral locking plates come in small and large fragment sizes. Both blade plates and proximal femoral locking plates come in variable neck shaft angles depend-

Fig. 6.13  Proponents of the prone position in surgery cite ease of using the leg as a goniometer to dial in the correct degree of derotation

6  Orthopedic Hip Surgery for Patients with Cerebral Palsy

ing on the vendor, with 90, 100, and 130 being the most common options. Templating should be performed to measure the width of the neck, taking into account also age of the child. As a guideline, the width of the blade should be 50–80% the width of the neck. In children with GMFCS levels 3–5 and bilateral lower extremity involvement, bilateral VDRO is typical even if only one hip is currently displacing, as the natural history of both hips is likely progress to bilateral displacement. Children are felt to benefit from single-event multilevel surgery, addressing both hips at the same time, instead of one hip this year and the other in a subsequent year when it has become more displaced. Shared decision-making with parents and caregivers regarding bilateral surgery is encouraged. There is not yet a guideline for exactly when to operate on a hip that is displacing. Most surgeons would consider a hip with a MP of 30–40% as a “hip at risk”, and surgical interventions are typically considered when there is progression over 30% or when the MP is >40%. For nonambulatory children the goal should be to bring the neck shaft angle down to 90–100° (Fig.  6.14). Rotation can be built into the correction as necessary to improve positioning (decreased scissoring) and hip stability. For nonambulatory patients, the calculation is relatively a

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simple, as placing a fixed angle device directly along the axis of the neck will result in a neck shaft angle of the device (e.g. place a 90° blade up the neck, the neck shaft angle with be 90). In nonambulatory patients 2 cuts are typically made, one parallel to the blade and one perpendicular to the shaft, cutting out a 1-2 cm wedge of bone effectively reducing the tension on the muscles about the hip and improving the osteotomy surface contact area. For ambulatory children the goal should be to bring the neck shaft angle down to 115–125° (Fig.  6.15). For older children with lower risk of recurrence aim for the higher end, while for younger children with increased risk of recur-

Fig. 6.14  Intra-operative fluoroscopic x-ray demonstrating postoperative neck-shaft angle of 90–100° in a nonambulatory patient following varus osteotomies

b

Fig. 6.15  Intra-operative fluoroscopic x-rays of the right (a) and left (b) hips demonstrating a postoperative neck-shaft angle of 115 to 120 degrees in an ambulatory patient

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rence aim for the lower end. Excessive varus (less than 115–120°) will result in weakened abductor forces and should be avoided. Calculate where the blade should be placed by determining how many degrees of correction are required. Select the blade, 100° is most typical. Identify the axis of the neck. If the neck shaft angle is 150°, and 30° of correction are desired, with a plan to use a 100° plate, then the blade must be directed 20° inferior to the axis of the neck (Fig.  6.16). Placing the blade centrally or inferiorly is preferred, avoiding placement of the blade high in the neck. Ambulatory patients are typically not significantly shortened (large wedge is not resected) as this is felt to result in de-tensioning of the muscles and lead to increased weakness. For ambulatory patients a single cut is made, parallel to the blade, and when the shaft is brought to the plate. There may be a relatively small surface area of contact at the osteotomy site. The distal spike could be

Fig. 6.16  Schematic demonstrating calculation of the planned path for the blade plate chisel: Red lines demonstrate neck shaft angles of 160 degrees. The blue lines are 20 degrees inferior to the axis of the neck. Inserting a 100-degree blade will result in a neck shaft angle of 120 (100 + 20 = 120), while inserting a 90-degree blade will result in a neck shaft angle of 110 (90 + 20 = 110)

osteotomized by a few millimeters to improve contact at the surgeon’s discretion, but excessive bone excision should be avoided to limit shortening. Another option is to cut the bone perpendicular to the femoral shaft and with plate fixation the proximal “spike” can be placed in the intramedullary canal adding further stability. In children undergoing only rotation, the blade plate can still be used, or a proximal femoral locking plate can be used. For children >9 years of age requiring only rotation, IM nail correction could also be considered.

Technique The patient is placed supine with a bump under the operative sacrum. A longitudinal incision is made at the lateral hip starting at the greater trochanter prominence and extending distally. This may be extended further proximally or distally once down to bone and it is clear where the plate will need to sit. The tensor fascia lata is split longitudinally. The bursa is feathered off with cautery. The vastus lateralis is elevated anteriorly in an L fashion, with the transverse portion of the L performed distal to the trochanteric apophysis and in the most tendinous portion of the vastus lateralis to afford later robust repair. A small cuff of vastus lateralis muscle is left posteriorly, and care is taken to identify and cauterize perforating blood vessels (Fig.  6.17). Sub-periosteal exposure of the proximal femur is obtained. By hand,

Fig. 6.17  The vastus lateralis is elevated anteriorly with the underlying periosteum. Homan-type retractors retract the vastus lateralis anteriorly to allow full exposure of the proximal femur

6  Orthopedic Hip Surgery for Patients with Cerebral Palsy

place a guide wire up on the anterior surface of the femoral neck staying on bone, to serve as a guide to the patient’s anteversion (Fig.  6.18). Place a guidewire centered anterior to posterior in the neck parallel, matching the anteversion of this wire, and direct it proximally as templated to provide the desired degree of valgus correction. On the AP view, the wire should enter just above the calcar. With the hip and knee flexed, the leg is brought into abduction using a large retractor to retract the posterior soft tissues so they do not impinge and bend the guidewire. On the frog lateral view, the wire should be central in the neck (Fig. 6.19). As the bone is often soft, predrilling the site of the chisel entry is typically not required. Advance the blade parallel to the axis of the femur. Building in a few degrees of extension is reasonable if there is a hip flexion bias. A guide exists to assist in directing the blade in the intended path (Fig. 6.20), and the tuning fork can be used to rotate the chisel to help redirect it as necessary. The blade should be placed as deeply as possible, without breaching the physis or the inferior cortex. Place a K wire proximal to the guidewire, and a second wire distally, just proximal to the patella. Place the distal wire bicorti-

a

Fig. 6.18 (a) The more anterior wire sits temporarily on the anterior neck, serving as a guide to the patient’s anteversion. (b) Fluoroscopy view showing the manually

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cally to limit displacement. Aim for the wires to be placed parallel in the axial plane, though this is not mandatory provided you measure and record the starting relative position of the wires. Stand at the foot of the bed and use a goniometer to measure the relationship between the wires and record this. Scoring the bone with an osteotome, saw, or marking with cautery can serve as a secondary measure of rotation in the event the K wires displace. Back the blade out slightly to help remove the rest of the way once the osteotomy is complete. A “hockeystick” device is used to mark the distance below the blade at which point the osteotomy should be made. Score the path of the intended osteotomy, parallel to the blade. Use an oscillating saw to cut the osteotomy, with retractors placed in a subperiosteal position anterior and posterior. Complete the osteotomy with the saw or with a straight osteotome. Place a sharp reduction forceps about the greater trochanter for proximal control, and gently remove the chisel. Replace the chisel with the blade plate on the inserter. The plates are built with a medializing offset to avoid lateralization of the shaft which can create problematic genu valgum, especially in ambulatory patients. Remove the distal lat-

b

placed k-wire along the femoral neck (the proximal wire) which can be used as a reference to place the guidewire for the blade plate

E. Dodwell et al.

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Fig. 6.19  On the frog lateral view, the wire and chisel should be central in the neck

Fig. 6.21  The angle between the wires guides derotation at the osteotomy site

Fig. 6.22  Intra-operative fluoroscopic pelvis view demonstrating final osteotomy position and fixation in a nonambulatory child Fig. 6.20 The flexion-extension guide demonstrates where the plate will sit in the proximal segment, allowing for flexion or extension in the osteotomy if desired

eral few millimeters from the proximal fragment so the plate can be seated more deeply. Use a Verbruge-type clamp to reduce the femoral shaft to the plate. Derotate as templated, using the relative rotation between the k-wires and a goniometer to guide the degree of rotational correction (Fig. 6.21). Place the first 2 screws in compression and then fill the remaining holes with locking screws if poor bone quality is present. Many plates now have a screw just distal to the blade that can be placed ideally locking or directed free

as necessary. If the blade backs out during manipulation/reduction of the shaft, this screw below the blade should be placed prior to reducing the shaft. Save final fluoroscopic AP and a lateral view (Fig. 6.22). Irrigate and close the wound in the routine layered fashion. Sterile dressing of surgeon’s choice is applied to cover the incision.

Aftercare/Rehab Whether using a blade plate or a proximal femoral locking plate, patients should be no more than toe touch weight-bearing for the first 3  weeks.

6  Orthopedic Hip Surgery for Patients with Cerebral Palsy

Patients