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2010 Course AANEM 57th Annual Meeting Québec City, Québec, Canada

2010 Courses AANEM 57th Annual Meeting Québec City, Québec, Canada 10AD Advancing neuromuscular, musculoskeletal, & electrodiagnostic medicine American Association of Neuromuscular & Electrodiagnostic Medicine Spasticity

Debabrata Ghosh, MD, DM Stephen Kishner, MD John R. McGuire, MD Geoffrey Sheean, MD, FRACP

AANEM 57th Annual Meeting Québec City, Québec, Canada

Printed by Johnson Printing Company, Inc. AANEM Course Spasticity iii Spasticity

Contents

CME Information iv

Faculty v The Pathophysiology of Spasticity 1 Geoffrey L. Sheean, MBBS, FRACP Comprehensive Adult Spasticity Management 5 John R. McGuire, MD Management of Spasticity in Children 9 Debabrata Ghosh, MD, DM Phenol for Spasticity Management 19 Stephen Kishner, MD iv

Course Description Spasticity can be a significant problem in upper motor neuron disorders. Consequences of spasticity can include the development of contractures or chronic pain, functional problems with self-care and mobility, seating problems, difficulty sleeping, as well as cosmetic appearance problems. A good understanding of the pathophysiology of spasticity is essential for proper management of this problem. This course will aid the physician understand this pathophysiology. Furthermore this course gives a guide to the evaluation and comprehensive management of spasticity in both pediatric age groups as well as adults.

Intended Audience This course is intended for Neurologists, Physiatrists, and others who practice neuromuscular, musculoskeletal, and electrodiagnostic medicine with the intent to improve the quality of medical care to patients with muscle and nerve disorders.

Learning Objectives Upon conclusion of this program, participants should be able to: (1) identify pathophysiology of spasticity. (2) perform an evaluation of an individual with spasticity. (3) identify different treatments available for spasticity management. (4) summarize indications and pros and cons of different spasticity treatments. (5) improve diagnosis of spasticity and management of patients with spasticity.

Activity Profile This enduring material activity is a reproduction of the printed materials from a course at the AANEM Annual Meeting (October 6-9, 2010). Physician participation in this activity consists of reading the manuscript(s) in the book and completing the clinical and CME questions.

Release Date: January 10, 2011 Expiration Date: January 10, 2014. Your request to receive AMA PRA Category 1 Credits™ must be submitted on or before the credit expiration date. Duration/Completion Time: 2 hours

Accreditation and Designation Statements The American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AANEM designates this enduring material for a maximum of 2.0 AMA PRA Category 1 Credit(s)™. Physicians should claim only the credit com- mensurate with the extent of their participation in the activity. AANEM Course Spasticity v v Spasticity

Faculty

Debabrata Ghosh, MD, DM Stephen Kishner, MD Staff Professor of Clinical Medicine Child Neurology Center Section of Physical Medicine and Rehabilitation Pediatric Spasticity and Movement Disorders Program Louisiana State University School of Medicine Neurological Institute New Orleans, Louisiana Cleveland Clinic Dr. Kishner is professor of clinical medicine and Physical Medicine and Cleveland, Ohio Rehabilitation Residency Training Program Director at Louisiana State Dr. Ghosh attended medical school at the Medical College of Calcutta in University School of Medicine in New Orleans. He is board certified in Calcutta, India. He completed a pediatric and neurology residency at the physical medicine and rehabilitation with subspecialty boards in neuro- Postgraduate Institute of Medical Education and Research in Chandigarh, muscular medicine and pain medicine. Dr. Kishner is board certified by India. His pediatric neurology fellowship was completed at the Cleveland the American Board of Electrodiagnostic Medicine. He also has a Masters Clinic. Dr. Ghosh is board certified in both child neurology and elec- of Health Administration. trodiagnostic medicine. He is currently a faculty member at the Cleveland Clinic. His special interests include movement disorders and spasticity in children, as well as electromyography.

Dr. Sheean is on the Advisory Board for Ipsen. Any conflict of interest was resolved according to ACCME Standards. Dr. McGuire is on the Allergan and Medtronix Speakers Bureaus. Any conflict of interest was resolved according to ACCME Standards. All other authors/faculty have nothing to disclose. Course Chair: Stephen Kishner, MD

The ideas and opinions expressed in this publication are solely those of the specific authors and do not necessarily represent those of the AANEM. vi

John R. McGuire, MD Geoffrey Sheean, MD, FRACP Associate Professor Director Director of the Spasticity Management and Stroke Rehabilitation EMG and Neuromuscular Servias Programs University of California Department of Physical Medicine and Rehabilitation San Diego, California Medical College of Wisconsin Dr. Sheean is the director of electromyography (EMG) and neuromuscular Milwaukee, Wisconsin services at the University of California, San Diego. He graduated from Dr. McGuire is an associate professor at the Medical College of medical school, internal medicine residency, and neurology residency Wisconsin in the Department of Physical Medicine and Rehabilitation. in Australia. He underwent further training and performed research in He is director of the Spasticity Management and Stroke Rehabilitation clinical neurophysiology at The National Hospital for Neurology and Programs and is actively involved in training residents and fellows. He Neurosurgery, Queen Square, London. Following that, he joined the staff received his medical degree from the University of Minnesota and com- at Queen Square and St. Mary’s Hospital, Paddington, as a consultant pleted his residency in physical medicine and rehabilitation and a fellow- clinical neurophysiologist. While at Queen Square, he developed an inter- ship in stroke rehabilitation at the Rehabilitation Institute of Chicago. est in botulinum toxin treatment, particularly for task-specific focal hand Dr. McGuire is board certified by the American Board of Electrodiagnostic dystonia and spasticity, and in the pathophysiology of spasticity. He later Medicine. His research interests include quantifying motor dyscoordina- moved to the University of California, San Diego. tion after upper motorneuron lesions, maximizing motor recovery and optimizing spasticity management. AANEM Course Spasticity viivii

Please be aware that some of the medical devices or pharmaceuticals discussed in this handout may not be cleared by the FDA or cleared by the FDA for the specific use described by the authors and are “off-label” (i.e., a use not described on the product’s label). “Off-label” devices or pharmaceuticals may be used if, in the judgement of the treating physician, such use is medically indi- cated to treat a patient’s condition. Information regarding the FDA clearance status of a particular device or pharmaceutical may be obtained by reading the product’s package labeling, by contacting a sales representative or legal counsel of the manufacturer of the device or pharmaceutical, or by contacting the FDA at 1-800-638-2041. AANEM Course Spasticity 1

The Pathophysiology of Spasticity

Geoffrey L. Sheean, MBBS, FRACP Clinical Professor of Neurosciences Director, Neuromuscular Division University of California, San Diego San Diego, California

INTRODUCTION Table 1 Types of motor overactivity in upper motor neuron syndrome Following a lesion of the upper motor neurons, several types of muscle overactivity can develop. Spasticity is a well-known type of this muscle overactivity and is a form of hypertonia that is velocity- Hyperkinetic Hypokinetic dependent and length-dependent and is due to hyperexcitability (involuntary movements) (impairment of movement)* of tonic stretch reflexes. However, there are several other forms of Spasms (flexor, extensor, adductor) Spasticity muscle or motor overactivity that can be seen (see Table 1). Most Great toe extension Static spastic dystonia of these are thought to arise as a result of disinhibition of various spinal reflexes caused by interruption of the upper motor neuron Associated reactions Spastic co-contraction pathways. However, the mechanisms underlying one form of motor Mass movements overactivity—spastic dystonia—are unclear. It is important to Action-induced spastic dystonia understand that these types of motor overactivity, although often seen together in various combinations, are caused by separate and * Includes active and passive movement distinct spinal mechanisms and are not just some variations of spasticity. spinal cord and separate from each other. All these pathways arise in the brainstem but only the dorsal reticulospinal tract receives input from the cortex, which is excitatory. These anatomical and func- SPINAL REFLEXES AND SUPRASPINAL CONTROL tional differences allow for different clinical patterns determined by the location and extent of the lesion. Whether the hyperexcit- Spinal reflexes are under supraspinal control by descending motor ability of spinal reflexes is simply due to a shift of physiological pathways that are predominantly inhibitory or excitatory. In humans, balance to net disinhibition, the way that heart rate is determined it appears that the corticospinal or pyramidal tract contributes very by a balance between sympathetic and parasympathetic drive, is little to the upper motor neuron syndrome. Other upper motor unknown. Neural plasticity changes, such as collateral sprouting neuron pathways (parapyramidal) are more important. or denervation hypersensitivity, also have been proposed. Recently, down regulation of a potassium-chloride cotransporter (KCC2) The main inhibitory pathway is the dorsal reticulospinal tract, has been found in the rat model of spinal cord injury. This leads to which ascends in the spinal cord adjacent to the corticospinal tract. impaired postsynaptic inhibition and spasticity and can be reversed The main excitatory pathways are the ventral reticulospinal tract by brain-derived neurotrophic factor (BDNF). and the vestibulospinal tract, which are located elsewhere in the 2 The Pathophysiology of Spasticity AANEM Course

MOTOR NEURON EXCITABILITY Patients with upper motor neuron lesions often exhibit abnormal While net disinhibition of spinal reflex pathways appears to play a cocontraction of agonist and antagonist muscle pairs during active central role in the development of these motor overactivities, other movement, which clearly interferes with movement. For example, mechanisms have been postulated. For example, muscle spindle hy- active extension of the elbow is impaired by simultaneous cocon- persensitivity as a result of increased gamma efferent drive was sug- traction of elbow flexors. It could be argued that the action of the gested as a possible mechanism of increased static (tendon reflexes) elbow extensors produces a passive stretch of the elbow flexors, elic- and tonic (spasticity) stretch reflexes. However, evidence of this has iting a tonic stretch reflex in the elbow flexors, similar to spasticity. not yet been found. Another possibility is increased intrinsic excit- However, isometric studies where stretch of the elbow flexors did ability of the motor neurons and evidence of this has been found in not occur show cocontraction. In other studies, contraction of the cat models of spasticity and in humans with spasticity. The mecha- antagonist muscle (e.g., elbow flexors) occurred before contraction nisms underlying this intrinsic hyperexcitability is an increase in of the agonist muscles (e.g., elbow extensors) had begun. In some persistent inward currents (PIC), which are strong determinants of cases, the antagonist contraction overwhelms the agonist contrac- the level excitability of a motor neuron and are under the control of tion producing the opposite movement. Patients attempting to descending serotonergic and noradrenergic pathways. Following an extend their fingers to open the hand often experience increased acute spinal lesion, persistent inward currents decrease dramatically flexion of the fingers. Attempted dorsiflexion of the ankle may leading to hypoexcitability of the motor neurons and a loss of reflex result in plantarflexion. This indicates that the upper motor neuron activity. This corresponds with the period known as spinal shock. signal for contraction is not confined to the agonist muscles alone, Later, persistent inward currents recover and become increased probably due to failure of reciprocal inhibition, most likely at the above baseline, producing plateau potentials leading to spontane- level of the spinal cord. ous and exaggerated flexor spasms. While motor overactivity, which is considered a positive phenom- Many spinal reflex pathways have been studied electrophysi- enon in the upper motor neuron syndrome, can interfere with ologically in spasticity and many have been found to be abnormal. active movement, it is the negative phenomena, such as weakness, However, it has been difficult to correlate any single spinal reflex incoordination, and fatigue, which produced most impairment of abnormality with the presence and severity of spasticity. Currently, movement. Spasticity and spastic hypertonia can interfere with reduction of reciprocal 1a inhibition and of autogenetic 1b inhibi- passive movement, as can soft tissue stiffness, joint calcification, tion are strong candidates. and contracture. Joint calcification and contracture limit the range of movement, whereas soft tissue stiffness increases the resistance to movement (i.e., tone) and possibly also the range of movement. CLINICAL EVALUATION Contracture can exist without hypertonia. The neurological consequences of an upper motor neuron lesion and the biomechanical One difficulty studying spasticity clinically and electrophysi- complications are not separate (see Figure). ologically is determining whether spasticity is actually present. In an upper motor neuron lesion, hypertonia is often produced UMN by a combination of spasticity and stiffness of soft tissues. Thus, in some studies, hyperreflexia of tonic stretch reflexes has been absent in patients thought to have spasticity clinically. Recognizing the difference in hypertonia due to spasticity and hypertonia due Motor Weakness to soft tissue stiffness is difficult but important for therapeutic Overactivity reasons. Hypertonia due to soft tissue stiffness will not respond to •Spasticity antispasticity medications or chemodenervation. The often used •Spastic clinical scales for evaluating spasticity is the Ashworth or Modified Dystonia Immobilization at short length Ashworth scale, which cannot distinguish spasticity from soft tissue hypertonia. The Tardieu scale seems to do this better because it relies on the velocity dependence of spasticity. Needle electromyog- Hypertonia Soft tissue raphy (EMG) and examination under anesthesia can be helpful. changes

Contracture DISORDER OF MOVEMENT

Because spasticity, by definition, is a passive entity, evaluated with Figure The neurological consequences of an upper motor neuron lesion and the biomechanical complications are not separate. the subject at rest, its relevance to movement has been questioned. Studies have shown that tonic stretch reflexes in actively con- tracting muscles are not exaggerated in patients with spasticity. UMN = upper motor neuron lesion However, natural reflex modulation during functional movements is impaired, which could interfere with movement. AANEM Course Spasticity 3

OTHER TYPES OF MOTOR OVERACTIVITY • Hypertonia can be due to spasticity, soft tissue hypertonia, Flexor spasms and extensor spasms are well recognized, particularly or, most often, both. Determining the relative contributions in patients with spinal cord injury. These appear to be due to exag- of each to clinical hypertonia can be difficult but will dictate geration of existing flexor and extensor reflexes. management.

Spastic dystonia is a term coined by Denny-Brown to explain sus- • Motor overactivity can interfere with movement, mostly tained involuntary contractions of muscles that were not driven by through spastic cocontraction and spastic dystonia. reflexes in monkeys with upper motor neuron lesions. For example, there might be tonic contraction of elbow flexors in the absence of • Spastic dystonia can be dynamic and only induced by action. stretch or of any stimulation that could provoke a flexor spasm. The There may be no spasticity at rest. contraction continued even after section of the relevant dorsal roots indicating that it was not a peripherally driven reflex. However, that • Neurological and biomechanical consequences of an upper does not necessarily indicate that spastic dystonia can not be modi- motor neuron lesion are interactive and need to be managed fied. For example, when the monkeys were inverted, elbow flexion together. changed into tonic elbow extension. In humans subjects, spastic dystonia can either increase or decrease with tonic stretch. • Understanding the basic physiological and molecular mechanisms, such as persistent inward currents and receptor modula- As in basal ganglia disorders, spastic dystonia can be purely action- tion, could lead to improved treatment for spasticity. induced. For example, a hemiplegic patient can have normal lower limb tone at rest but upon standing and attempting to walk can develop the well-known hemiplegic posture of extension at the knee and plantarflexion and inversion of the ankle. Furthermore, standing and walking can evoke elbow, wrist, and finger flexion.

CONCLUSIONS

The pathophysiology of spasticity has a number of clinical implications:

• Spasticity is a narrowly defined entity and only one of several types of motor overactivity that can occur after an upper motor neuron lesion, which mostly have separate pathophysiological mechanisms. Terminology precision is essential.

• The clinical pattern of motor overactivity is largely determined by the location and extent of the lesion. 4 AANEM Course AANEM Course Spasticity 5

Comprehensive Adult Spasticity Management

John R. McGuire, MD Associate Professor Director of the Spasticity Management and Stroke Rehabilitation Programs Department of Physical Medicine and Rehabilitation Medical College of Wisconsin Milwaukee, Wisconsin

INTRODUCTION Table 1 Upper motor neuron syndrome Spasticity is only one component of the motor dysfunction result- ing from upper motor neuron lesions. Each component of the Positive symptoms upper motor neuron syndrome (UMNS) should be addressed to Spasticity 1 properly manage these patients (see Table 1). Establishing realistic Spastic co-contraction treatment goals with the patient and the interdisciplinary team can optimize outcomes. Obtaining patient assessment of both active Spastic dystonia and passive function and identifying areas of problematic muscle Flexion/extension synergistic muscle patterns overactivity can help target which intervention is most appropriate Reflex release phenomena for each patient. Recent treatments now are available to manage Negative symptoms muscle overactivity but need to address other components of the UMNS for optimal functional outcomes. Weakness, fatigue Loss of dexterity, balance Loss of selective muscle control ASSESSMENT Rheologic changes

Patient assessment should include both static and dynamic mea- Contracture, fibrosis, atrophy sures to determine an overall treatment strategy. Assessments from physical and occupational therapists, as well as input from the the muscles reaction to stretch but it controls for the velocity of the patient and their caregivers, are essential for establishing patient- stretch and measures the angle at which the catch or clonus occurs. specific goals and an optimal treatment plan.2 The “spasticity angle” is a neural component that is amenable to treatment.6 Clinical, electrophysiological, and biomechanical measures have been used to quantify spasticity (see Table 2). The most commonly Electrophysiologic tests such as the H-reflex, H/M ratio, F wave, used clinical measures of spasticity are the Ashworth and modified and tonic vibration reflex (TVR) have used to been used to quan- Ashworth scale (see Table 3).3 The modified Ashworth scale adds tify spasticity.7 Historically, these measures tend to correlate poorly an additional intermediate grade (1+), but has less inter-rater reli- with the degree of spasticity. The soleus H/M ratio can be used to ability than the Ashworth scale.4,5 The Tardieu scale (see Table 4) confirm the effects of intrathecal baclofen (ITB) during the ITB has advantages over the Ashworth scale in that it not only quantifies trial and potentially for troubleshooting. In a prospective case series 6 Comprehensive Adult Spasticity Management AANEM Course

Table 2 Measures of spasticity provide a controlled stretch of a limb while measuring torque, joint angle, and reflex electromyographic (EMG) activity.9 Clinical Ashworth scale Modified Ashworth scale The assessment of patients with UMNS should also include measures of motor control (see Table 5). The Fugl-Meyer scale is a Tardieu scale reliable and validated measure of upper and lower extremity motor Oswestry scale impairment based on the natural progression of functional return Spasm frequency scale after a stroke.10 The Fugl-Meyer scale has been demonstrated Tone assessment scale to have high intra-rater and inter-rater reliability, and it can be completed in 10-20 minutes. Decline of function on the Fugl- Electrophysiological H/M ratio Meyer scale has been shown to correlate closely with the severity of Biomechanical Servo-control device spasticity. The functional test for the hemiparetic upper extremity was developed at Rancho Los Amigos Hospital and consists of 17 Table 3 Ashworth scale graded tasks with seven levels of difficulty.11

0 No increased tone Table 5 Measures of motor control 1 Slight increase in muscle tone, manifested by a catch and release or by minimal resistance at the end of the range of motion when the Clinical Fugl-Meyer scale affected part is moved in flexion or extension Upper extremity test (Rancho, Wolf) 2 More marked increase in muscle tone through most of the range of motion, but affected part(s) easily moved Timed walk, get up and go test 3 Considerable increase in muscle tone, passive movement difficult Electrophysiological Dynamic eletromyography 4 Affected part(s) rigid in flexion or extension Biomechanical Motion analysis systems

Table 4 Tardieu scale Dynamic polyelectromyographic (PEMG) recordings can be used to identify the timing and duration of muscle over activity in poststroke spastic hypertonia. PEMG recordings can be helpful Quality of muscle reaction for understanding muscle involvement for potential treatment 0 No resistance with chemodenervation, chemical neurolysis, or surgical release 1 Slight resistance of individual muscles. For example, in the patient with a spastic flexed elbow, PEMG can be used to identify spastic co-contraction 2 Catch followed by a release of the elbow flexors and extensors.12 By combining PEMG with 3 Fatigable clonus (< 10 s) kinematic data from a motion analysis laboratory, the primary 4 Infatigable clonus (> 10 s) upper or lower extremity motor dysfunction can be localized. Quantitative gait analysis can differentiate quadriceps overactivity from hip flexor weakness or poor ankle mechanics as the cause of Angle of muscle reaction (spasticity angle) stiff-legged gait.13 = Angle of arrest at slow speed YV1 − Angle of catch as fast speed YV3

INTERVENTIONS Velocity of stretch V1 As slow as possible Prior to any intervention the goals of treatment should be estab- V2 Speed of limb falling under gravity lished. Goals for spasticity management include symptomatic relief V3 As fast as possible or reduced impairments and improvement in active or passive function. Once the patient goals are established, complimentary treat- 9 stroke patients, 17 traumatic brain injured patients, and 4 anoxic ments can be initiated (see Table 6). Certain conditions that can brain injured patients treated were with a 50 µg bolus of ITB. Five increase spasticity should be addressed prior to initiating additional hours post bolus there was a reduction of the H/M ratio from 62% treatment (see Table 7). ± 28% to 14% ± 19% and the Ashworth score decreased from 2.4 ± 0.7 to 1.5 ± 0.6 on the more involved side.8 This study suggests that the soleus H/M ratio may be more sensitive than the Ashworth FOCAL/SEGMENTAL TREATMENTS score in detecting a physiologic response to an ITB bolus. Chemodenervation with botulinum neurotoxin (BoNT) and chem- Biomechanical measurements of spasticity using a servo-controlled ical neurolysis with phenol can be used alone or in combination to motorically driven device can provide a more reliable measure of effectively manage focal spasticity. Phenol is reviewed elsewhere in spasticity but is limited to the research laboratory. The device can this course. BoNT causes a chemical denervation by inhibiting the release of acetylcholine (Ach) from the peripheral cholinergic nerve AANEM Course Spasticity 7

Table 6 Complimentary treatments GENERALIZED TREATMENTS The most commonly used oral antispasticity medications are ba- Rehabilitation treatments clofen, tizanidine, valium, dantrium, and cloanzepam (see Table Reduce nociceptive input 8). The pharmacology and dosing have been extensively reviewed in other publications.19 Because somnolence and weakness are Focal/segmental treatments common side effects of oral medications, low doses at night may be Nerve/motor point blocks useful in select patients with difficulty sleeping because of muscle Tendon transfer/lengthening spasms. As with most medications it is suggested to start low and go Generalized treatments slow. Rather than higher doses of one medication, a combination of lowers doses of two medications may be better tolerated.20 Also as Oral/intrathecal medications with most medications they should be tapered off. Rhizotomy Table 8 Pharmacologic treatments Table 7 Factors that increase spasticity GABA system Baclofen, benzodiazepines Infections: urinary tract infections, pneumonia, cellulitis Ion Flux Dantrium, gabapentin Bowel impaction Monoamines Tizanidine, clonidine Kidney stone GABA = gamma-aminobutyric acid Deep venous thrombosis Ingrown toe nails ITB has become a widely used method for the management of intractable spasticity of cerebral or spinal origin. ITB can be safe and effective Changes in temperature in hemiparetic spastic patients as well as quadriparetic and paraparetic Psychological factors patients.21 The advantages of ITB include the procedure’s reversible, Diet, medications the noninvasive dose adjustments, its potential for fewer side effects Disease progression than oral drugs, the evidence to support efficacy in reducing spasticity, and its potential to improve function, comfort, and care. Potential side endings. When injected intramuscularly, these toxins cause focal effects include hypotonia, somnolence, nausea/vomiting, headache, denervation and a graded muscle weakness. Numerous studies and dizziness, and paresthesias. Catheter and procedural complications metaanalysis support the use of BoNT in the treatment of focal may occur. Overdose rarely happens. Baclofen withdrawal is more spasticity. The dose is adjusted based on patient weight, muscle common and can be a life-threatening situation.22 size, and desired effect. The duration of effect depends on dose, dilution, size of the muscle, injection technique, and postinjection therapy. On average, the duration of effect is usually 3-4 months. Rehabilitation Treatments The most common side effects are adjacent muscle weakness, pain with injection, hematoma, and transient fatigue or nausea.14 BoNT Collaboration with physical and occupational therapists is essential can be injected by muscle palpation, with needle EMG guidance, to the effective management spasticity. The therapist can help with low-intensity electrical stimulation or ultrasound guidance. More patient evaluations, education, and establishing patient specific goals. study is needed to delineate which technique is most effective. The primary focus of these therapies is aimed at providing prolonged stretch to shortened muscles and tendons, reducing muscle overactiv- Surgical procedures are typically reserved for those patients with ity, strengthening weak muscles, and improving motor control (see muscle or tendon shortening who have not responded to the less Table 9). Unfortunately, there is a significant variation in the use of invasive procedures or as a last resort. Tendon transfer, release, or these therapies and a lack of controlled trials.23 lengthening are the most common orthopedic procedures. The Table 9 Rehabilitation interventions split anterior tibial tendon transfer (SPLATT) and tendon Achilles lengthening (TAL) have been used to manage the spastic equinovarus foot.15 In a 1-year study of 21 stroke patients 1 year after a Inhibitory/serial casting SPLATT, 83% reported good or excellent results. All ambulatory Weight bearing patients had improved gait and 35% were able to discontinue their Neurofacilatory techniques orthosis. Poor surgical outcomes were associated with nonambulatory status.16 Eighteen patients with spastic hand deformities had Electrical stimulation improved prehension after release of the flexor–pronator origin Aquatic therapy 17 and step-cut lengthening of flexor pollicis longus. PEMG may Electromyographic biofeedback be useful in identifying which patients would benefit most from Constraint-induced movement therapy orthopedic procedures.18 Robotic training Partial weight support treadmill training 8 Comprehensive Adult Spasticity Management AANEM Course

9. Schmit BD, Dhaher Y, Dewald, JP, et. al. Reflex torque responses Surface electrical stimulation has been shown to reduce muscle to constant velocity movements in spastic elbow muscles: theo- atrophy, enhance strength, and possibly reduce spasticity. retical analyses and implications for quantification of spasticity. Ann Unfortunately, most studies have shown limited functional im- Biomed Eng 1999;27:815-829. provement and many patients are unable to tolerate the electrical 10. Fugl-Meyer AR, Jaasko L, Leyman I, et. al. The post-stroke hemiplegic patient: Scand J Rehabil Med 1975;7:13. stimulation. A new device combines a wrist–hand orthosis with 11. Wilson DJ, Baker LL, Craddock JA. Functional test for the hemipa- functional electrical stimulation (FES) of wrist and finger flexors retic upper extremity. Am J Occup Ther 1984,38:159-164. and extensors during a repeated prehension exercise paradigm. The 12. Mayer N, Esquenazi A. Muscle overactivity and movement dysfunc- NESS H200™ is a neuroprosthesis that is well tolerated and has tion in the upper motoneuron syndrome. Phys Med Rehabil Clin N been shown to reduce spasticity and improve function.24 Similar Am 2003;14:855-883. commercially available devices for the leg are the NESS L300™ and 13. Kerrigan DC, Karvosky ME, Riley PO. Spastic paretic stiff-legged the WalkAide. Although these devices are well tolerated and effec- gait: joint kinetics. Am J Phys Med Rehabil 2001;80:244-249. tive more study is needed. 14. Brin M. Botulinum toxin: chemistry, pharmacology, toxicity, and im- munology. Muscle Nerve 1997;6:S146-S168 15. Keenan MA. The orthopedic management of spasticity. J Head CONCLUSION Trauma Rehabil 1987;2:62-71. 16. Edwards P, Hsu J. SPLATT combined with tendo Achilles lengthening for spastic equinovarus in adults: results and predictors of surgi- Comprehensive spasticity management is essential to optimizing cal outcome. Foot Ankle 1993;14(6):335-338. functional outcomes. Careful patient assessment, realistic goals, 17. Pinzur MS. Upper extremity surgery for the spastic patient. Phys Med knowledge of the functional peripheral anatomy, and technical Rehabil: State of the Art Reviews1994;8(3):535-546. skills are essential to safely and effectively manage spasticity. 18. Keenan MA, Fuller DA, Whyte J, et. al. The influence of dynamic polyelectromyography in formulating a surgical plan in treatment of spastic elbow flexion deformity. Arch Phys Med Rehabil REFERENCES 2003;84(2):291-296. 19. Gracies JM, Nance P, Elovic E, McGuire JR. Traditional pharmaco- 1. Mayer N. Clinicophysiologic concepts of spasticity and motor dys- logical treatments for spasticity. Part II. General and regional treat- function in adults with an upper motoneuron lesion. Muscle Nerve ments. Muscle Nerve 1997; (6):S92-S120. 1997;(6):S1-S13. 20. Nance P. Alpha adrenergic and serotonergic agents in the treatment 2. Scanlan S, McGuire J. Effective collaboration between physician and of spastic hypertonia. Phys Med Rehabil Clin N Am 2001;12(4):889- occupational therapist in the management of upper limb spasticity 905. after stroke. Top Stroke Rehabil 1998;4:1-13. 21. Ivanhoe CB, Francisco GE, McGuire JR, Subramanian T, Grissom 3. Ashworth B. Preliminary trial of carisoprodol in multiple sclerosis. SP. Intrathecal baclofen management of poststroke spastic hyper- Practitioner 1964;192:540-542. tonia: implications for function and quality of life. Arch Phys Med 4. Bohannon RW, Smith MB. Interrater reliability on a modified Rehabil 2006;87:1509-1515. Ashworth scale of muscle spasticity. Phys Ther 1987;67:206-207. 22. Coffey R, Ridgely P. Abrupt intrathecal baclofen withdrawal: man- 5. Pandyan AD, Price CIM, Barnes MP, et. al. A Review of the proper- agement of potentially life-threatening sequelae. Neuromodulation ties and limitations of the Ashworth and modified Ashworth Scales 2001;4(3):142-146. as measures of spasticity. Clin Rehabil 1999:13;373-383. 23. Watanabe T. The role of therapy in spasticity management. Am J 6. Gracies JM, Renton R. Sandanam J, et. al. Short-Term effects of Phys Med Rehabil 2004;83:S45-S49. dynamic Lycra splints on upper limb in hemiplegic patients. Arch 24. Alon G, Stibrant K, Geurts CH, et. al. A home based, self-admin- Phys Med Rehabil 2000;81:1547-1555. istered stimulation program to improve selected hand functions of 7. Sehgal N, McGuire JR. Beyond Ashworth. Electrophysiologic quanti- chronic stroke. NeuroRehabil 2003;18(3):215-225. fication of spasticity. Phys Med Rehabil Clin N Am 1998;9;949-979. 8. Stokic DS, Yablon SA, Hayes A. Comparison of clinical and neuro- physiologic responses to intrathecal baclofen bolus administration in moderate-to-severe spasticity after acquired brain injury. Arch Phys Med Rehabil 2005;86:1801-1806. AANEM Course Spasticity 9

Management of Spasticity in Children

Debabrata Ghosh, MD, DM Staff Child Neurology Center Pediatric Spasticity and Movement Disorders Program Neurological Institute Cleveland Clinic Cleveland, Ohio

INTRODUCTION the concept of development of spasticity secondary to upper motor neuron lesion is very useful to understand various management Spasticity is defined clinically best as: Velocity-dependent increase options of spasticity, it is too simplistic, and, the underlying mecha- in resistance to passive stretch of a muscle or a group of muscles nism is much more complex. Pure corticospinal or cortconuclear when a joint is moved passively. This phenomenon is explained by lesion does not produce spasticity, rather, it produces hypotonia. quantitative measurement of spasticity by Tardieu (see Fig. 1). In Lesions of other motor tracts—vestibulospinal, reticulospinal, and that figure, to quantify the degree of spasticity of knee flexor, the rubrospinal—in varying combinations may underlie development ankle joint is dorsiflexed passively at a slow pace until the resistance of increased muscle tone in the form of spasticity. Whatever the is felt, the angle of dorsiflexion (R2) is measured at that position, mechanism, this diagram simplistically helps in understanding the then the same movement is repeated at a faster rate and the angle mechanism of various modalities of spasticity management. So at which the resistance is felt first (R1) is noted. The difference in far, spasticity management is concerned with the management of the angle R1 and R2 is primarily due to dynamic spasticity. This hyperactivity of the lower motor neuron starting from the anterior method not only diagnoses spasticity but also helps in distinguish- horn cell to the anterior nerve root to peripheral nerve to muscle ing pure spasticity from other reasons of hypertonia—rigidity, con- and from the muscle sensory organs (spindles, Golgi tendon tracture, and dystonia. Early spasticity can be present only during organs) to the sensory nerve to the dorsal root and finally synapsing active limb movement, whereas passive movement may not show with the anterior horn cell, thus completing a monosynaptic reflex increased resistance. For example, on passive abduction of the hips arc. This hyperactivity of the lower motor neuron, no more under in supine posture, an infant may not demonstrate increased muscle inhibitory control of the upper motor neuron explains most of the tone, whereas lifting up the infant suddenly, holding at the axilla, features with spasticity. Thus far, most of the management options may produce hip adduction in the form of scissoring. This concept are based on controlling this lower motor neuron hyperactivity. helps in identifying the spasticity at an early stage. Another example Unless therapies such as stem cell therapy prove effective in dealing is in a child with spastic diplegia. Formal muscle tone examination with primary pathology in brain or spinal cord, physicians have at lying posture may be normal, but while walking one can observe very little control over the upper motor neuron, the primary site of the spasticity kicking in, thus affecting the walking. pathology in disorders producing spasticity. Ongoing physical and occupational therapies may help in the recovery or regeneration Spasticity is produced as part of the upper motor neuron syndrome, process through new synapse formation, new nerve endings, and classically defined as the involvement of the neuraxis from the cor- activation of the dormant areas to take over the function of the tical motor neuron to the lower motor neuron (anterior horn cell damaged areas through the process called plasticity. Thus physical at the spinal cord or motor cranial nerve nuclei at the brain stem). and occupational therapies (PT/OT) and orthotic management are Figure 2 demonstrates the upper and lower motor neurons. Though the default in the management program for spasticity. Whatever 10 Management of Spasticity in Children AANEM Course

Figure 1 Modified Tardieu method for evaluation of spasticity. management is proscribed these are absolutely essential, delivered either formally under supervision or through caregivers after teach- ing them.

Spasticity may not be parallel with weakness. This is an important point to consider before deciding to begin spasticity management. Sometimes spasticity may act as a splint to support the limb in presence of weakness; as example, quadriceps spasticity may help in ambulation in a child with spastic diplegia. In that case controlling quadriceps spasticity may expose underlying weakness and thus a loss of ambulation. Therefore, clinicians must determine a goal Figure 2 Upper and lower motor neurons. prior to embarking on the spasticity management. On the contrary, in another child with spastic diplegia, ankle planteflexors, ham- strings, and/or hip adductors may be too tight to act as mechanical Source: http://www.medtronic.com/physician/itb/ hindrance to ambulation. In these situations, lowering the excess muscle tone in those selected muscle groups will help the gait and may prevent falls, making the walking more energy efficient. are absolutely essential in management of any child with spasticity. In addition to ongoing effective PT/OT and use of orthotics when Spasticity management in children is a challenging problem as the needed, the specific management can be broadly categorized (see disorders with spasticity have many complications and comorbidi- Table 1) as: ties involving multiple systems. For example, a child with a spastic quadriplegic form of cerebral palsy may have seizures and behav- 1. Oral medications in the form of baclofen, benzodiazepines, ioral problems requiring pediatric neurological expertise. There tizanidine, and dantrolene. Each of these medications has may be contracture of spastic muscles leading to muscle shortening unique usefulness and a side effect profile and should be with consequent joint and bony deformities requiring pediatric managed by a clinician familiar with them. orthopedic expertise. Appropriate PT/OT and orthotic measures AANEM Course Spasticity 11

CAUSES OF SPASTICITY IN CHILDREN Table 1 Various treatment modalities for spasticity Table 2 shows various causes commonly responsible for devel- Physical therapy/occupational therapy/orthotics opment of spasticity in children arranged in order of the most Oral medication common. Disorders with spasticity in children alternatively can be classified as: 1) static—secondary to remote brain or spinal Benzodiazepines cord injury or stroke, hypoxia/ischemia, treated brain tumor, con- Dantrolene genital brain malformation, treated hydrocephalus, meningitis or Tizanidine encephalitis with complications, or 2) progressive—secondary to Baclofen leukodystrophies, hereditary spastic paraplegias, rarely multiple sclerosis, late manifestation of neuronal storage disorders, untreated Chemodenervation using botulinum toxin hydrocephalus, and nontreatable brain tumor. This distinction Intrathecal baclofen pump is very important for a long-term management approach. Also Selective dorsal rhizotomy important is the comorbidities that may be relative or absolute Orthopedic surgery contraindication to some surgical management or botulinum toxin injection. The common comorbidities are listed in Table 3. Neuronectomy/neurolysis Table 2 Etiology of spasticity in children

2. Botulinum toxin injection for focal or multifocal spasticity or Cerebral Spinal focal severe component of generalized spasticity. The unique Cerebral palsy Myelitis, multiple sclerosis aspect of this management is confinement of the effect in the muscles injected. The injector has to be well trained in select- Head injury Tumor ing various muscles with spasticity for proper localization and Stroke Ischemic injection under electromyographic (EMG) or electric stimula- Encephalitis Epidural abscess tor guidance. Meningitis Compression

3. Intrathecal baclofen pump where the baclofen is delivered Brain tumor Spinal tumor directly into the spinal subarachnoid space, thereby avoiding Brain malformation Spinal dysraphism systemic or central nervous system side effects like sedation. Hydrocephalus Syringomyelia There is a need for excellent coordination between the physical and occupational therapists, the electrodiagnostic (EDX) Table 3 Comorbidities associated with spasticity physician, and the pediatric neurosurgeon for selecting appropriate cases for intrathecal baclofen pump. Cognitive/behavioral concerns 4. Dorsal rhizotomy when spasticity is primarily confined to the Seizures lower limbs with preserved cognitive abilities. There is a need Dystonia and other involuntary movements for coordination between the pediatric neurosurgeon and the Bony and joint problems neurophysiologist for root stimulation and selection during Visual concerns—ROP/cortical blindness/strabismus the surgery. Speech concerns 5. Orthopedic surgeries (absolutely essential) in cases of promi- Feeding/nutritional concerns nent contracture, scoliosis, and secondary bony or joint de- Respiratory concerns formities. Drooling 6. Neurectomy or neurolysis—either cutting the nerve (neurec- Socioeconomic concerns tomy) or alcohol/phenol injection (neurolysis) of the nerve— supplying a severely spastic muscle with no possibility of ROP = retinopathy of prematurity attaining some useful function with time. EVALUATION OF SPASTICITY IN CHILDREN In considering multiple facets of management it is extremely important to coordinate the pediatric physical and occupational therapists, Modified Ashworth tone scale evaluates the resistance (degree of EDX physicians, neurosurgeons, orthopedic surgeons, and social force) needed to move a joint passively. This is a very easy-to-use workers to maximize the benefit of spasticity management in chil- bedside evaluation of spasticity with the following limitations: dren. Each center should have a multidisciplinary spasticity clinic 1) it becomes unreliable in the presence of dystonia; 2) it does not where these experts converge to evaluate and manage all the problems distinguish between various causes of hypertonias such as dystonias, faced by children with spasticity. One individual must be in charge of rigidity, contracture, voluntary resistance, muscle spasm (so the coordinating the care suggested by the spasticity clinic team. clinician has to be extremely cautious about its implication in the clinical context); and 3) it does not reflect the function. 12 Management of Spasticity in Children AANEM Course

The Tardieu method possibly may be more reflective of the actual 4. Prevention and/treatment of painful spasms, either spontane- degree of spasticity. The principle behind this method is the veloc- ous, nocturnal, or during stretching, thus mitigating the suf- ity dependence of the spasticity. However, (as shown in Fig. 1) this fering of the child and improving their quality of life. method is a bit cumbersome, requiring measurement of the angles of the joint. When a joint is moved passively slowly, the angle of 5. Improvement of range of movement, prevention or delaying the joint at the maximum range of movement (R2) is measured and develop in the of contractures or bony or joint deformities, this angle is compared to the angle (R1) when the joint is moved thus delaying or preventing the need for major orthopedic faster, thus causing the spasticity to emerge far before the R2 angle. interventions such as tendon lengthening, tendon transfer, or The difference between these angles can be extrapolated to be due osteotomies. In this context it is worthwhile to remember that to spasticity. This method appears to be very useful in focal or mul- orthopedic interventions are an absolute necessity in some tifocal spasticity for monitoring the treatment response, too. For children, but, on principle, these are performed not to treat quantification of spasticity, a simple hand-held dynamometer can spasticity but to treat the complications of unmanaged spastic- measure the force needed to move a joint against resistance. ity either due to the biological reasons or due to lack of proper early institution of spasticity management. Hip adductor angle, popliteal angle, and determination of range of movements of various joints, both active and passive, are good ways of assessing the stiffness due to spasticity or other causes mentioned Consequences of Untreated Spasticity earlier. The consequences of untreated spasticity include: From a functional perspective, the functional score of each limb (0-100), the disability score (0-4), the spasm score, the pain score • Disuse atrophy and weakness of the muscles are also simple but useful tools. For children with cognitive problems or for younger children, the parents can be asked the questions • Development of muscle/tendon or soft tissue fibrosis or con- to determine the scores. Time to walk 25 ft in ambulatory child is tracture another functional measure. • Secondary bony or joint deformities When the whole child is considered in the context of all the comor- bidies (Table 3), the Gross Motor Functional Classification System • Painful muscle spasm/pain is a handy way to assess motor functional status, the Functional Independence Measure for Children (Wee-FIM) is a good measure • Poor hygiene and consequent infection of overall functional abilities, and activities of daily life (ADL) by Barthel is a good alternative measure. The Pediatric Quality of Life • Problems in caregiving Index (PQLI) may reflect the effect of intervention on spasticity. The Goal Attainment Scale may be another way to follow the treatment response. The details of the these methods are beyond VARIOUS OPTIONS FOR SPASTICITY MANAGEMENT IN the scope of this discussion. CHILDREN

Selective Dorsal Rhizotomy REASONS TO TREAT SPASTICITY In selective dorsal rhizotomy, lumbar laminectomies are performed Each child with spasticity should be assessed individually by a followed by exposure of the dorsal nerve roots in the spinal canal. multidisciplinary team, as mentioned earlier. This team should They are dissected very cautiously to isolate individual rootlets, work closely with the parents or care givers to determine the goals then individual rootlets are electrically stimulated to determine of spasticity management in each case. The following are some whether they are hyperactive. For assessing the hyperactive rootlet, broader reasons to treat spasticity: each rootlet is stimulated by a needle electrode with concomitant EMG recording of various lower limb muscles. If the effect spreads 1. Improved ambulation and greater independence which may to other segments either on the same side or other side, or the effect improve the child’s confidence to help them develop their full in the same root-innervated muscles is much prolonged even after a potential. brief single stimulus, the rootlet is considered hyperactive and then severed. Thus, this procedure requires a prolonged careful micro- 2. Ease of care in nonambulatory children which may vary from surgery in which an experienced neurosurgeon works together with easy transfer, dressing, and undressing. an experienced electrophysiologist. Needle EMG recordings during the rootlet stimulation are shown in Figures 3 and 4. Figure 3 3. Improved perineal, axillary, and palmar hygiene through better shows a normal response after right L4 rootlet stimulation, whereas stretching and cleaning those areas which are prone to infec- Figure 4 shows an hyperactive left L3 rootlet. tion. This is a permanent procedure which requires prolonged intensive physical therapy with extensive stretching and strength training for AANEM Course Spasticity 13

Figure 3 Normal needle electromyography response after right L4 rootlet Figure 4 Abnormal needle electromyography after single stimulus of left stimulation. L3 dorsal rootlet. a year after the surgery. Ideal candidates are children with cerebral Benzodiazepines palsy, aged 3-10 years with normal cognition, and good lower limb muscle strength. The benefits are 1) segmental/subsegmental— Benzodiazepines act at presynaptic receptors linked to gamma- decreased spasticity, improved strength on intensive therapy, im- aminobutyric acid (GABA)-A receptors and alter the chloride proved mobility, and persistent improvement over more than 10 channel. As GABA-A receptors are widely distributed, these years; and 2) suprasegmental—improved speech pattern, oropha- medications have more central nervous system side effects such as ryngeal control, improved fine motor control, and even improved drowsiness, generalized weakness, ataxia, memory impairment, and cognition. The mechanism behind this suprasegmental improve- cognitive issues. There may be issues with drug abuse and with- ment is unclear. This may be related to general improvement in the drawal symptoms with benzodiazepines. Rarely, there may be para- well being of the child. doxical aggression. The most common one used is diazepam—both enteral and injectable preparations are available. So the oral route Table 4 shows the pros and cons of selective dorsal rhizotomy. easily can be changed to intravenous if an oral or enteral intake is not allowed due to any reason. The usual range of oral dose of diazepam is 0.2-0.8 mg/Kg/day. Clonazepam is available primarily in MEDICAL MANAGEMENT OF SPASTICITY IN CHILDREN enteral form, the maximum dose is up to 3 mg/day. The side effect profile is similar to that of diazepam. Children may tolerate oral or systemic medication better than adults. The medications commonly tried are baclofen, benzodiazepines, dantrolene, and, rarely, tizanidine. The general principle is Dantrolene to start the medications at as low as possible and then very slowly escalate the dose. The night-time dose should be increased first to Dantrolene primarily acts on the muscle membrane and inhibits mimic physiologic sleep awake state. calcium release from the sarcoplasmic reticulum. Hypertonia, hyperreflexia, and range of movement scissoring may improve but 14 Management of Spasticity in Children AANEM Course

Table 4 Pros and cons of selective dorsal rhizotomy

Pros Cons One time procedure; may be Prolonged surgery requiring expert an advantage to families with neurosurgeon and electrophysiology poor availability of medical team. care. No implanted hardware, thus Permanent procedure with no risk of infection is minimized; adjustment possible later; if too no recurring complication. many rootlets are cut, there may be permanent weakness and sensory or bladder involvement, and, if too few are cut, it will not be effective. Effective in expert hands of Not useful for upper limbs. neurosurgeon with proper electrophysiological selection of the roots. If ineffective or effectivity Needs committed extensive physical is lost later, can proceed therapy to achieve gain; if not the to other modalities such as weakness may be more overt. baclofen pump or botulinum toxin injection. with limited objective functional improvement. The limiting side effects are drowsiness, weakness, nausea, diarrhea, and, most im- portantly, hepatotoxicity (1.8%).

Tizanidine

Tizanidine is an alpha-2 adrenergic agonist which is beneficial for muscle spasticity and spasm. The side effect profile is also sedation and tiredness. Efficacy is modest at best. It can be used as adjuvant along with other antispasticity medication or modalities of management.

Baclofen

Chemically baclofen is 4-chlorophenyl-gamma aminobutyric acid; as obvious from Figure 5, this is GABA-mimetic, primarily on the Figure 5 Baclofen structure, similar to γ-aminobutyric acid (GABA). GABA-B receptor. It inhibits supraspinal excitatory and hyperactive spinal cord synapses through inhibition of calcium influx into Intrathecal Baclofen Pump the presynaptic terminal, thus reducing presynaptic excitatory neurotransmitter release. Baclofen also inhibits substance P and To deliver the medicine directly around the site of its action, some dopamine neurons. This may explain the analgesic effect of baclofen can be injected at the spinal subarachnoid CSF space baclofen in addition to an antispasticity effect. Baclofen does not through a programmable, implantable pump delivering the medi- have any intravenous formulation. After oral administration it is cine continuously. The rate of infusion can be varied and prero- rapidly absorbed, partially metabolized in liver, and largely excreted grammed through a handheld computer (programmer). The unchanged in the kidneys. The dose is not that closely related to age intrathecal baclofen (ITB) pump is refilled at intervals by a transcu- or weight. Oral dose of 30-90 mg will result in cerebrospinal (CSF) taneous injection. Figure 6 diagramatically shows the pump system. concentration of 12-95 ng/ml, whereas an intrathecal dose of 400 The pump lying inside the parietal abdominal wall is connected mcg is associated with a CSF concentration of 380 ng/ml. That via a catheter to the CSF space entering through the lumbar area, is why the concept of intrathecal baclofen pump came up. Side the tip is then advanced upwards to the desired segmental level effects of oral baclofen are dose related—excessive hypotonia and where the spasticity is at its maximum. The indication is that at weakness, impaired cognition, confusion, memory and attention least a moderate degree of spasticity responds well to oral baclofen difficulties, and, rarely, paradoxical excitation and insomnia. but systemic side effects of sedation and cognitive issues develop. Severe scoliosis, poor trunk muscle strength, and the presence of a AANEM Course Spasticity 15

Table 5 Pros and cons of intrathecal baclofen pump

Pros Adjustable and reversible effects Less invasive than surgery Longterm reduction in spasticity Cons Implanted device Frequent return visits—refills, adjustments, and new batteries Risk of infection and catheter malfunction Baclofen withdrawal can be life threatening Requires compliance

Table 6 Intrathecal baclofen pump complications in adults and children13

Figure 6 Intrathecal baclofen pump system. Procedures 218 Revision of Catheter Infection (%) over 5 years pump (%) revision (%) Adult 72 2.7 14 5 Source: http://www.clevelandclinic.org/health/health-info/pictures/pumpn- bdy.gif Pediatric 146 3.4 24 25

Botulinum Toxin Injection concomitant ventriculo-peritoneal shunt and other hardware inside the body are relative contraindications for the ITB pump. For the Botulinum toxin is produced by the bacteria Clostridium botu- best case selection it is recommended to have a trial of ITB in which linum. Among seven neurotoxins produced by various serotypes, the children are subjected to objective evaluation before and serially botulinum toxin type A (Botox®, Dysport®) and type B (Myobloc®) after ITB injection. The pros and cons of the ITB pump have been are purified to be used as one of the safest management options for highlighted in Table 5. The major complications are highlighted spasticity and/or dystonia among many other conditions including in the Table 6. Regarding scoliosis progression following the ITB drooling of saliva which is a very common comorbid condition pump, current literature does not support such relationship. The associated in spastic children with cerebral palsy. The chemical cost-effectiveness of ITB pump has been well analyzed by Edgar structure of the botulinum toxin has been shown in Figure 7; it and colleagues (2007). The incremental cost per quality-adjusted has two chains—a light and a heavy chain connected by disulfide life-year for identical cohorts of children treated with an ITB pump bridge. Figure 8 (on page 17) shows the mechanism of action of was analyzed. For the ITB group the 5-year cost of treatment in- botulinum toxin. The molecule enters the presynaptic junction at creased by $49,000 relative to alternative treatment. However this the neuromuscular junction, then is cleaved at the lysosome. The was accompanied by average gain of 1-2 quality-adjusted life-years. light chain is the active compound which cleaves the docking pro- The net result was an incremental cost-effective ratio of $42,000 teins, synaptobrevin or SNAP-25, which normally helps fusion of per quality-adjusted life-year, below the $50,000 to $100,000 the acetylcholine vesicles to the presynaptic membrane to release range, accepted as very cost-effective. acetylcholine in the neuromuscular junction. This produces an action potential that propagates along the muscle membrane. This toxin is very effective for focal or multifocal spasticity and/ Selective Dorsal Rhizotomy or Intrathecal Baclofen Pump? or dystonia and also is used effectively in the focal component of a generalized spasticity or dystonia. When compared to neurectomy Significant involvement of the upper limbs and cognitive/behav- and dorsal rhizotomy, the effect of a botulinum toxin injection is ioral affection will contraindicate rhizotomy. For candidacy of the reversible. This reversibility is however a double-edged sword as the ITB pump the body weight should be preferably above 25 lb, or effect also is reversed along with any side effects. So, there is need there may be a mechanical problem implanting the pump in the for reinjection every 3-5 months. There is no cognitive or central parietal abdominal wall. The presence of overt weakness in the nervous system side effect. The overall side effect profile is excel- muscles, even if there is primary lower limb involvement with lent, the response is very predictable. Concomitant salivary gland preserved cognition, is a contraindication for the dorsal rhizotomy. injection helps drooling significantly. For children below 3 years or above 10 years of age rhizotomy is not recommended. Associated movement disorder may be against Efficacy of botulinum toxin has been evaluated by the therapeu- the rhizotomy; whereas dystonia, if present, may respond well to tic and technology assessment subcommittee of the American an ITB pump. Academy of Neurology in 2008 (Table 7). They found six class I studies showing beneficial effect of botulinum toxin for spasticity, 16 Management of Spasticity in Children AANEM Course

Neurectomy/Neurolysis

Surgical sectioning of a nerve (neurectomy) supplying a single muscle or a group of muscles and phenol or alcohol block of the nerve (neurolysis) are performed very rarely in children with spasticity. The reasons may be irreversibility of the neurectomy and pain involved in neurolysis, possibly further contributed by excellent response to botulinum toxin injections. However in specific situations in which spasticity is severe in a single muscle group, as in the hip adductor, if ambulation or use is not a concern, a deci- sion may be made to perform these procedures even in children.

SPASTITICY MANAGEMENT: CHILDREN VERSUS ADULTS

General Management

The younger developing brain has more plasticity, thus early intervention with therapy is much more beneficial in children. If therapy is delayed or inappropriate there may be misdirected plasticity. Children in general tolerate oral medications better than adults.

Growth spurts in adolesecent children with spasticity may increase the muscle and limb length discrepancy, producing more stiffness, more progression of orthopedic deformities, worsening of gait in ambulation, hip dislocation, and bony and joint pain. Thus, more active intervention is needed in adolescence. Scoliosis also progresses rapidly during adolescence, so its management is of paramount importance in addition to other antispasticity management. For example, employing an ITB pump is very challenging when a scoliosis rod is inserted. Additionally, management of spasticity may be challenged by adolescent behavior that results in oft repeated poor compliance in therapies.

There is another important aspect to be kept in the mind when evaluating a child with motor abnormalities following early brain injury. Though the brain pathology may be static, the motor abnormalities may increase. For example, hypotonic cerebral palsy may progress with age to spastic quadriplegic type. Dystonia and Figure 7 Chemical structure of botulinum toxin. some other movement disorders such as chorea and tremors may appear years after after the inciting brain insult. Pseudoregression with increasing motor difficulties during acute stress such as fever thus their recommendation regarding botulinum toxin in man- and infection elsewhere may lead to a lot of costly investigations if agement of spasticity in children is class A (should be offered). the clinician is not aware of this phenomenon. However this option cannot be a primary option for management of a generalized spasticity as the dose requirement may be too high. Its use should be reserved in focal or multifocal spasticity, or it can Specific Management be used to manage the most severely spastic muscles in combination with other modalities of management such as the ITB pump The specific management of spasticity in children versus adults or dorsal rhizotomy. Very recently, the United States Food and includes: Drug Administration has approved the use of botulinum toxin in adults with spasticity. Use in children with spasticity still comes 1. Generalized spasticity in children under the age of 3 years, or with a black box warning that the family should be alerted to weight less tha 25 lb—PT/OT, modest dose of oral antispas- seek immediate medical attention if the child develops dysphagia, ticity medications, added with botulinum toxin in selected dyspnea, dysphonia, or generalized weakness following botulinum muscles, may help buy time for eligibility for dorsal rhizotomy toxin injection as part of systemic botulism. or an ITB pump. AANEM Course Spasticity 17

Figure 8 Mechanism of action of botulinum toxin.

Table 7 Report of therapeutic and technology assessment subcommittee of the American Academy of Neurology: summary for botulinum toxin in the treatment of spasticity

Disorder Class No. of Outcome measures Adverse events Conclusions Recommendations* Limitations subjects Adult spasticity 14 class 1 906 Tone (Ashworth), Focal weakness, Established safe A Methodologic passive fx: range pain and effective challenges in of motion, cleaning, study design hygiene, pain Probably B Limited outcome Active fx: Goal effective measures to Attainment Scale, demonstrate Frenchay; global efficacy in active disability (MD/pt) functional gains Childhood 6 class 1 376 Tone (Ashworth), Pain, Established safe A Best evidence for spasticity in passive fx: range weakness, falls, and effective equinus virus cerebral palsy of motion, active fx: incontinence, gait/video/kinematic dysphagia analysis; global disability (MD/pt)

*Classification of recommendations is available on the Neurology® website at www.neurology.org.

A = should be offered, B = should be considered, C = may be considered, fx = function, MD = physician, pt = patient

From: Simpson DM and colleagues.1 18 Management of Spasticity in Children AANEM Course

3. Guillaume D, et al. A clinical study of intrathecal baclofen using 2. Worsening of spasticity after years of dorsal rhizotomy: must a programmable pump for intractable spasticity. Arch Phys Med rule out new onset superimposed dystonia; an ITB pump may Rehabil 2005;86:2165-2171. be considered at that point. 4. Hsieh JC, et al. Intrathecal baclofen in the treatment of adult spasticity. Neurosurg Focus 2006;21(2):E5. 3. Spasticity following hemispherectomy (primarily upper limb, 5. Knutsson E, et al. Plasma and cerebrospinal fluid levels of baclofen (Lioresal) at optimal therapeutic responses in spastic paresis. J Neurol hemineglect, weakness combined), PT/OT, constraint-in- Sci 1974;23:473-484. duced movement therapy, and botulinum toxin injection are 6. Plassat R, et al. Treatment of spasticity with intrathecal Baclofen ad- the best combination. ministration: long-term follow-up, review of 40 patients. Spinal Cord 2004;42:686-693. 4. Children with spasticity and ventriculoperitoneal (VP) shunt— 7. Biering-S F, et al. Spasticity-assessment: a review. Spinal Cord one should be very cautious in employing an ITB pump as 2006;44:708-722. there is an increased risk of infection and also possible baclofen 8. Dawes WJ, et al. Microfracture of a baclofen pump catheter with overdose. intermittent under and overdose. Ped Neurosurg 2003;39:144-148. 9. Francisco GE, et al. In : Roth EJ, ed. Consensus panel guidelines for the use of intrathecal baclofen therapy in poststroke spastic hyperto- CONCLUSION nia. Top Stroke Rehabil 2006;(13)4:74-85. 10. Ivanhoe CB, et al. Intrathecal baclofen management of poststroke spastic hypertonia: implications for function and quality of life. Arch Children with spasticity can be managed very effectively through a Phys Med Rehabil 2006;87:1509-1515. multimodality approach managed by multidisciplinary team com- 11. Steinbok P. Selection of treatment modalities in children with spastic posed of a child neurologist, neurosurgeon, orthopedican, thera- cerebral palsy. Neurosurg Focus 2006;21(2):E4. pists, and physiatrists. PT/OT is a must in each case. When therapy 12. Tardieu G, et al. Muscle hypoextensibility in children with cere- alone is unable to control spasticity, one should combine oral bral palsy: II. Therapeutic implications. Arch Phys Med Rehabil medication with a botulinum toxin injection in selected muscles 1982;63(3):103-107. to gain maximum control of spasticity with tolerable side effects. 13. Vender JR, et al. Identification and management of intrathecal An ITB pump can be effectively combined with botulinum toxin. baclofen pump complications: a comparison of pediatric and adult An ITB pump can be implanted after dorsal rhizotomy if spastic- patients. J Neurosurg 2006;104(1 Suppl):9-15. ity gets worse with time. Combining orthopedic and neurosurgery 14. Albright AL. Neurosurgical treatment of spasticity and other pediatric movement disorders. J Child Neurol 2003;18:S67-S78. procedures may be convenient for the patient and family.

SUGGESTED READING

1. Simpson DM, et al. Botulinum neurotoxin for the treatment of spasticity. Neurology 2008;70:1691-98. 2. De Lissovoy G, Matza LS, Green H, Werner M, Edgar T. Cost- effectiveness of intrathecal baclofen therapy for the treatment of severe spasticity in children. J Child Neurol 2007;22(1):49-59. AANEM Course Spasticity 19

Phenol for Spasticity Management

Stephen Kishner, MD Professor of Clinical Medicine Section of Physical Medicine and Rehabilitation Louisiana State University School of Medicine New Orleans, Louisiana

INTRODUCTION There was significant interest in the specific effects of phenol on neural tissue used intrathecally. Iggo and Walsh17 studied the Doppler was one of the first physicians to use phenol as a neuro- effects on spinal roots of cats and concluded that small fibers were lytic agent. In 1925, he painted phenol on rabbit ovarian vessels more susceptible to phenol than larger fibers. Nathan and Sears29 and noted subsequent vasodilatation. Eight years later, in 1933, also looked at the effect of phenol on spinal nerve roots of cats the Russian literature reports Nechaev used phenol as a local an- The study found that: 1) phenol had a temporary local anesthetic esthetic agent. Mandle, in 1950, reported the successful injection effect in addition to its longer term effects on spasticity, 2) aqueous of phenol for permanent sympathectomy in 15 patients without phenol solutions could cause reversible or irreversible block of complications. Both Haxton and Boyd simultaneously reported nervous conduction in both myelinated and unmyelinated nerve paravertebral injections of phenol for peripheral vascular disease in fibers, 3) the smallest fibers were blocked before larger fibers, and 1949. In 1955, Maher reported the use of phenol by intrathecal 4) recovery is most likely to occur in the fastest conducting fibers of injection for intractable cancer pain.24 Nathan28 along with Kelly the “A” group and are least likely to occur in the smaller “C” fibers. and Gautier-Smith,19 all simultaneously reported intrathecal injec- Histopathological changes after the injection of 7.5% to 15% tions of phenol for relief of spasticity in 1959. phenol solutions in glycerol in the lumbosacral subarachnoid space of cats show that there was damage to myelin sheaths and axons, as well as vasculitis, arachnoiditis, and peripheral demyelination, in INTRATHECAL PHENOL FOR SPASTICITY: HISTORICAL USE addition to occasional infarction of the lower spinal cord.2

As mentioned above, the earliest uses of phenol for relief of spas- The effects of intrathecal phenol on nervous tissue was also ticity was by the intrathecal method.3,l9,23,28,31 These early studies evaluated in humans. Needle electromyography (EMG) of the utilized up to 20% phenol solutions in glycerol. A major concern leg muscles was performed on patients after intrathecal phenol with the use of phenol intrathecally included significant complica- treatment for spasticity.31 The needle EMG was performed before tions such as loss of residual motor function or sensation as well as and after phenol injection. Starting 12 days after treatment with loss of sphincter control. Weaker solutions of 5% phenol in glyc- phenol, signs of denervation were observed. Another study looked erin produced effects of shorter duration; however, the 5% phenol at the posterior spinal roots after intrathecal injection in humans. solution intrathecally still produced considerable side effects related This study showed severe degeneration of myelin affecting the to the sphincters. It did not appear that phenol caused any note- outer zone of posterior roots predominately, with involvement of worthy effect on the cerebrospinal fluid, and no cases of meningitis all types of fibers, both large and small.3 There was no selectivity of were reported. effect by phenol on small fibers compared to large fibers. This was similar to Baxter’s findings in cats.2 20 Phenol for Spasticity Management AANEM Course

PHENOL PERIPHERAL NERVE AND MOTOR POINT HISTOPATHOLOGY OF NERVE AND MUSCLE AFTER BLOCKS PHENOL INJECTION

The search for a simpler, safer, and practical treatment of spastic- Several studies looked at the histopathology of the peripheral nerve ity led Khalili and colleagues22 to use 2% and 3% aqueous phenol after phenol nerve block.4,26,27 Different concentrations of phenol, solutions for selective peripheral nerve blocks. These injections ranging from 1% to 6%, showed no evidence of selective destruc- were used in a diverse group of 20 patients with severe spasticity. tion of smaller versus larger fibers. There was evidence of perineural The spasticity was secondary to various causes including traumatic inflammatory cell infiltration, axonal degeneration, and myelin spinal cord injury, vascular accidents, cerebral palsy, and transverse sheath degeneration. The amount of degeneration did appear to myelitis. The minimal amount of phenol used to produce an ef- be concentration dependent. Wallerian degeneration was seen with fective block was 0.5 cc of a 2% phenol solution. The maximum neural regeneration. amount was 5 cc’s of a 3% solution. Overall the average amount of phenol solution used for each nerve block was 2 cc’s of a 2% to 3% Halpern13 reviewed histological studies of muscles in rats and dogs solution of aqueous phenol. Phenol motor point blocks were first after phenol motor point blocks. The localized points of injection described by Halpern and Meelhuysen in 1965.14 They initially proved to be intramuscular nerves that were near the terminal in- performed phenol motor point blocks with 3% aqueous phenol, nervation band, or frequently proximal in the mixed nerves, which however, they found that the duration effect was limited and in- includes the motor branch and the muscle afferents, running in the creased the aqueous phenol solution to either 5% or 7%. Because neurovascular bundle in the intrafascicular regions of the muscles. the postinjection observation period was limited, any difference in It was found that these phenol motor point blocks caused nerve the longterm duration of effects between the 5% and 7% groups destruction with secondary denervation and atrophy with muscle could not be determined. Thirty-nine patients were injected for a necrosis. Both the nerve and muscles showed evidence of regenera- total of 122 muscles. Improvement of tone was achieved in 114 of tion, which was well established by 2 months and almost complete 122 muscles. by 3 months.

PATHOPHYSIOLOGY OF PHENOL ON PERIPHERAL SPASTICITY MANAGEMENT DECISIONS NERVES Treatment of spasticity must be made after full assessment of the Looking at the histopathological effects after phenol injections can patient, including discussion with any caregivers involved. Multiple be important in understanding the specific mechanisms of phenol issues should be considered, including if the spasticity is severe action. Fusfeld9 performed needle EMG examinations on a small enough for treatment, and, if untreated, will the spasticity lead group of hemiplegic patients approximately 1 month after phenol to permanent contractures. The patient should be evaluated to nerve or motor point blocks were conducted. Of the seven patients, determine if the spasticity is generalized or localized. Activities of three had needle EMG examinations prior to the administration of daily living, such as transfers, seating, driving, or self-care, should the phenol blocks and were found to be free of denervation. One be evaluated to see if spasticity is interfering. The patient should month after the phenol block, five of the seven patients had evi- be evaluated to assess if there is severe chronic pain that may be dence of denervation. The authors concluded that the alpha motor alleviated by a spasticity procedure. Finally, is the severity of the fibers are not all spared by nerve or motor point phenol blocks. spasticity problem worth the potential side effects of a phenol injection procedure? Khalili and Betts21 found, that in certain patients, voluntary movement emerged following phenol nerve blocks with no clinical evidence of sensory involvement. This was interpreted as a result INDICATIONS AND BENEFITS OF CHEMICAL NEUROLYSIS of the selective effect of dilute phenol on gamma fibers. In other WITH PHENOL patients, loss of voluntary motor activity and evidence of sensory impairment had been noticed which could be evidence of a more Chemical neurolysis with phenol should be considered as a treat- widespread effect on the peripheral nerve. Glass and colleagues11 ment for spasticity when other more conservative measures have studied needle EMG responses on 20 patients after performing not succeeded. Ideally, the spasticity to be treated should be local- phenol nerve and motor point blocks with either a 3% or 6% ized rather than generalized. There are times when more conserva- phenol aqueous solution. All the patients had needle EMG exami- tive measures such as oral medications may be contraindicated. For nations prior to the phenol injections and there was no evidence example, significant liver function abnormalities can prohibit use of denervation. After injections, virtually all patients who had 6% of certain antispasticity medications. Furthermore, not all medica- phenol nerve blocks showed evidence of denervation. On the other tions are approved for use in pediatric patients. Medications can hand, almost no one with motor point block at a 3% or 6% con- also cause significant sedation or deleterious effects on cognition. centration or phenol nerve blocks with 3% concentration showed evidence of denervation. The authors suggest that the 3% phenol Phenol chemical neurolysis may be useful in any stage of recovery. concentration produces a preferential paralysis of the gamma ef- In the acute period, it may help prevent loss of range of motion, ferents, without significantly effecting alpha motor activity that is such as trying to prevent plantar flexion contractures while in an affected by the 6% solution. AANEM Course Spasticity 21 intensive care unit. More commonly, it is used in the later stages in and convulsions.8 The main adverse reactions that have been seen the treatment of spasticity. after phenol motor point blocks have been few and consist almost entirely of mild local pain that lasts for a few days after the injec- Chemical neurolysis of individual muscle groups can have more tions. Occasionally, some local induration has been noted. This widespread effects by decreasing the stimulus for flexor or extensor was Halpern’s and Meelhuysen’s experience during a total of 394 synergy patterns. In addition, a decrease in spasticity in an agonist muscles injected in 95 patients.14 muscle can unmask active voluntary activity in a weaker antagonist muscle group. Thus, in certain cases, after phenol blocks are per- The major complication of phenol nerve blocks discussed in the formed, voluntary motor contraction may be observed that did not literature is that of paresthesias.5,16,21,32,35 After phenol nerve appear to exist prior to the nerve blocks.21 block, approximately 4% of patients will suffer paresthesias. In the vast majority of cases, the pain or paresthesias lasted from several days to a month. The complications generally did not PHARMACOLOGY OF PHENOL interfere with any functional gains obtained in the patients. A tight glove or sock was found to relieve discomfort.21 Paresthesias Phenol or carbolic acid, which was first isolated in 1834, is a or dysesthesias are less likely to be encountered in children, with benzene ring with one hydroxyl group. Lister introduced it to one study showing a 0.4% occurrence.37 When paresthesias medicine as an antiseptic in 1867. In its pure state, it is a colorless and dysesthesias persist, repeating the phenol nerve block can crystal that melts if heated to 38°C. At concentrations up to 6.7%, be curative. A more worrisome complication of paravertebral it is soluble at room temperature.34 phenol block is possible diffusion into the subarachnoid space. This can lead to bowel, bladder, or sexual dysfunction when the Phenol has a local denaturing effect on tissue protein. Furthermore, paravertebral blocks are performed in the lumbar area. Cervical it has an anesthetic effect, which can be of benefit during the proce- paravertebral blocks are never utilized due to the possibility of re- dure. It is bacteriostatic at a 0.2% concentration and bacteriocidal spiratory depression if there is any diffusion into the subarachnoid at a 1% concentration.8 Eighty percent of phenol is excreted by the space. kidney. Because phenol is a sclerosing agent, care should be taken not to inject it into vascular structures. Phenol does have systemic toxic effects.15 A toxic dose is estimated between 8 and 15 g. At INFORMED CONSENT toxic levels, tremors and convulsions may be seen. Phenol was initially available in glycerin for intrathecal uses; however, presently it Due to the above potential complications, informed consent must primarily is used in an aqueous solution for nerve and motor point be obtained when phenol blocks are performed. blocks. It is more effective in aqueous solutions than in glycerin.8 EQUIPMENT DURATION OF EFFECT The equipment most commonly used is a portable direct current The documented duration of the effect of phenol chemical neu- stimulator with a digital readout of the current intensity. The rolysis varies considerably and appears to be dose and concentra- cathode of the stimulator is connected to a Teflon®-coated needle. tion related. Generally, nerve blocks last longer than motor point With the Teflon coating, only the bevel of the needle is exposed, blocks. Khalili and Betts found an average phenol nerve block thus the effect of the stimulation is seen only at the point where lasted about 208 days with an average dose of 2 cc’s of a 2% to 3% the phenol is actually being injected. These needles vary in length, aqueous solution per nerve.21 Most commonly a 22 gauge is used; however, other gauges are available. The phenol is drawn up in a syringe and extension tubing Halpern and Meelhuysen15 reported on the duration of effect after is placed between the syringe of phenol and the stimulating Teflon- phenol motor point blocks using 5% aqueous phenol. In 84% of coated needle. The extension tubing helps prevent movement of the patients, the effect lasted 4 months or longer, and in 60% of the needle when the plunger of the syringe is depressed and the the patients, the effect lasted 6 months or longer. Repeat injections phenol is injected. produced similar responses to the initial injection. PEDIATRIC CONSIDERATIONS POTENTIAL COMPLICATIONS Griffith and colleagues discuss the use of anesthesia in phenol in- As previously mentioned, phenol is a sclerosing agent.14 Standard tramuscular neurolysis in young children with spasticity.12 Chloral procedure should therefore be to draw back on the syringe prior hydrate at 30 mg/kg of body weight can be given but must be to injecting to avoid intravascular injection. There is one docu- administered orally 90 minutes prior to the procedure. Griffith and mented case of a patient developing an arterial block in the upper colleagues also discuss general anesthesia as an option for treating extremity after receiving a median phenol nerve block requiring young children.12 an upper-limb amputation.10 Systemically administered phenol can stimulate the cerebrospinal fluid which could cause tremors 22 Phenol for Spasticity Management AANEM Course

ESTIMATION OF EFFECT WITH PRIOR LOCAL Thoracodorsal Nerve ANESTHETIC BLOCK To inject the thoracodorsal nerve, the needle is inserted at the mid- A local anesthetic block prior to a phenol block can give an estimation point of a line from the apex of the axilla to the inferior point of the of loss of function due to loss of spasticity. This also can be helpful if scapula. The needle should be angled upwards. Optimally for this there is any question of the degree of contracture versus spasticity in a procedure, the arm should be abducted to 90 degrees, if possible. potential area to be blocked. A trial local anesthetic block is commonly The thoracodorsal nerve is fairly superficial and can be found at an used when a spastic gait pattern is under consideration for phenol approximate depth of 1 to 1.5 cm. procedures. Sometimes lower extremity spasticity may help gait, and taking away the spasticity may cause deterioration of gait even though the upper extremity requires spasticity management. Since it is pos- Tibial Nerve sible that the spasticity may help gait, the local anesthetic block could predict potential improvement or deterioration of gait. However, a To inject the tibial nerve, the patient is placed in the prone position local anesthetic block as a trial for an ambulatory patient is not always with the leg to be injected resting on a pillow to maintain the knee analogous to a phenol block. With a local anesthetic block there is also in approximately 30 to 45 degree of flexion. The needle electrode is a sensory block which may affect gait as well. inserted at the apex of the popliteal fossa or at the popliteal crease at the level of the knee joint.7 DYNAMIC POLYELECTROMYOGRAPHY Sciatic Nerve Sometimes it is very difficult to know exactly what nerve or muscle in a limb is the primary muscle(s) that is (are) spastic. The sciatic nerve can be found at a point bisecting a line joining Polyelectromyography has been used to isolate the specific incrimi- the ischial tuberosity and the greater trochanter.7 With needle ma- nating muscles with regard to spasticity.36 nipulation it is possible to get primarily the tibial division or the peroneal division of the sciatic nerve at this point. NEEDLE LOCALIZATION TECHNIQUE Obturator Nerve In both phenol nerve and motor point blocks, placing the tip of the needle electrode in the precise location is critical for the success of The patient is placed in the supine position with the thigh in the block.14,22,30 At a superficial site over the area where the block is maximum adduction to inject the obturator nerve. The obturator planned, the skin is prepared and the needle is inserted. The electrical nerve divides into an anterior and posterior branch. The anterior stimulator is turned on, and the needle is moved until the appro- branch is generally injected first. The adductor longus tendon is pal- priate visible contraction of muscle is observed. Needle movement pated at the pubic tubercle. The needle is inserted approximately 2.5 continues until the least intensity of electrical current provides the cm distal from the origin at its lateral margin. The needle is directed desired maximum contraction in the muscle in which the spasticity is posteriorly and toward the head. For localization of the posterior being treated. The current output is decreased at this point until only branch, the needle is inserted approximately 1 cm deeper.1,7,33 a very slight contraction is seen. The required current is generally only a fraction of a millampere. At this point, any needle movement, even of a few millimeters, may result in loss of the stimulation. After Paravertebral Lumbar Block the injection of phenol, there should be a decrease or disappearance of the contraction of the muscle in response to the same ongoing The paravertebral lumbar blocks can be considered for hip flexor spas- electrical stimulation. When motor points are injected in a muscle, ticity. The L2, L3, and possibly the L4 nerves need to be injected. The there may be multiple sites in each muscle, with further probing of patient is placed in the lateral recumbent position on the side opposite the muscle to isolate other motor points. that to be injected with the back flexed. From the level of the iliac crest, which corresponds to L4, all the interspaces are marked off up to L2. The needle is introduced approximately 2.5 cm out from the spinous SPECIFIC ANATOMIC LOCALIZATION process. The needle is advanced until bone is reached, which is the transverse process. At this point, the needle is retracted and reintroduced Musculocutaneous Nerve with its point slightly more medially and inferiorly making a 20 to 45 degree angle with the sagittal plane. The needle tip is then advanced In the axillary approach, to inject the musculocutaneous nerve,20 slowly until the desired responses of the hip flexors are found.1,25 the patient is placed in the supine position and the shoulder is abducted. The shoulder also should be externally rotated with the elbow extended. The axillary artery should be palpated and pushed Median Nerve aside posteriorly. The needle is inserted just behind and beneath the tendon of the pectoralis major. The needle is advanced slowly in the The median nerve lies slightly medial to the brachial artery at the direction of the coracoid process. elbow. The nerve also lies under the bicipital aponeurosis. A point AANEM Course Spasticity 23

2.5 cm distal and anterior to the medial epicondyle of the elbow • Thigh adduction should be found. The needle is inserted at this point. The brachial • Anterior and posterior branches of the obturator nerve artery runs laterally to the median nerve. During the advancement can be considered. Retrospective analysis of 62 patients of the needle in this approach, a motor branch to the pronator teres has shown benefits with hygiene, pain, spasticity, and may be encountered and this can be blocked. range of motion with obturator phenol blocks.42

Upper extremity Recurrent Motor Branch of the Median Nerve • Shoulder internally rotated and adducted, elbow flexed and pronated, wrist and fingers flexed To inject the recurrent motor branch of the median nerve, the • For this upper extremity pattern seen in stroke and brain technique described for the thumb-in-palm deformity is utilized.18 injury patients, one approach is to start with the tho- Two intersecting lines are drawn on the palm. A line is drawn racodorsal nerve. After this injection, the entire upper starting from the web space of the thumb parallel to the proximal extremity pattern may improve and the upper extremity palmer crease. A second line is drawn parallel to the radial border of should be reevaluated. If there is still significant shoulder the long finger. At the intersection of these two lines the recurrent adduction spasticity then the next procedure that can be motor branch of the median nerve enters the thenar mass. At this considered is motor point blocks of the pectoralis major. point, the stimulating needle is inserted. Then going down the arm, the musculocutaneous nerve can be injected for elbow flexor spasticity, and the median nerve for median nerve distribution spasticity. Subscapularis Motor Point

The subscapularis motor point block has been described for the REPEAT PHENOL INJECTIONS treatment of the painful hemiplegic shoulder.6 To inject the subscapularis, the patient is positioned lying on his/her side with the Phenol blocks may be repeated when the effect diminishes; hemiplegic side up. The affected limb is positioned to produce as however, it may be more difficult to perform this localization on much winging of the scapula as possible. At the level of the spine repeated attempts. of the scapula, the needle is inserted just under the medial edge of the scapula. The needle is advanced close to the anterior surface of the scapula with the objective of localizing the point of maximal ADVANTAGES OF PHENOL COMPARED TO BOTULINUM internal rotation of the shoulder with the electrical stimulator. TOXIN

The advantages of phenol injections compared to botulinum toxin Tibialis Anterior and Tibialis Posterior Motor Points injections include: • Much lower cost Both the tibialis anterior and the tibialis posterior muscles may be • Longer lasting effect (However there are comparative studies injected for severe foot inversion. Approximately one third of the that say the opposite.)39 40 41 way down the tibialis anterior, an anterior approach is taken. Once • Quick onset with effects observed at time of procedure the tibialis anterior motor points are located, the needle is advanced • Ease of confirmation of the amount of spasticity reduction at straight through the interosseous membrane to locate the tibialis time of procedure posterior motor points. • Ability to block larger territory with a nerve block • Ability to treat more spastic muscle/nerve territories at one sitting COMMON PATTERNS OF SPASTICITY

The common patterns of spasticity include: DISADVANTAGES OF PHENOL COMPARED TO BOTULINUM TOXIN Lower extremity • Great toe extension The disadvantages of phenol injections compared to botulinum • Can use phenol motor point blocks to the extensor hal- toxin injections include: lucis longus • More potential complications, particularly dysesthesia risk • Ankle/foot equinovarus • More difficult technical procedure requiring greater operator • Depending on the incriminating spastic muscles, the tibi- skill and longer procedure time alis anterior and tibialis posterior motor points, and the • Need for compounding or hospital pharmacist with hood to tibial nerve, injection at the level of the knee may be of prepare benefit. • Hip and knee flexion • For hip flexion spasticity, paravertebral lumbar blocks at the L2, L3, and possibly L4 level may be helpful. 24 Phenol for Spasticity Management AANEM Course

COMBINING BOTULINUM TOXIN AND PHENOL 13. Halpern D. Histologic studies in animals after intramuscular neurolysis with phenol. Arch Phys Med Rehabil 1977;58:438-443. There will be occasions when there is consideration to use botuli- 14. Halpern D, Meelhuysen FE. Phenol motor point block in the num toxin to treat an adult or pediatric patient but the amount of management of muscular hypertonia. Arch Phys Med Rehabil botulinum toxin required exceeds the maximal recommended dose. 1966;47:659-664. It is easy to use phenol for large proximal muscles, or major nerve 15. Halpern D, Meelhuysen FE. Duration of relaxation after intramuscular neurolysis with phenol. JAMA 1967;200:1152-1154. territories, and use botulinum toxin for smaller distal muscles. This 38 16. Helweg-Larsen J, Jaconsen E. Treatment of spasticity in cerebral can be performed at the same time. palsy by means of phenol nerve block of peripheral nerves. Dan Med Bull 1969;16:20-25. 17. Iggo A, Walsh EG. Selective block of small fibers in the spinal roots PHYSICAL AND OCCUPATIONAL THERAPY COMBINED by phenol. Brain 1960;83:701-708. WITH PHENOL 18. Keenan MA, Botte MJ. Technique of percutaneous phenol block of the recurrent motor branch of the median nerve. J Hand Surg The addition of physical and occupational therapy in the overall 1987;12A:800-807. treatment of spasticity appears to improve outcomes.43 However, 19. Kelly RE, Gautier-Smith PC. Intrathecal phenol in the treatment of this has not been extensively or scientifically evaluated when com- reflex spasms and spasticity. Lancet 1959;2:1102-1105. bined specifically with phenol injections. Similarly, the same can be 20. Khalili AA, Betts BB. Isolated block of musculocutaneous and perineal nerves in the management of spasticity with special refer- said for serial casting when spasticity and contracture are present. ence to the use of a nerve stimulator. Anesthesiology 1967;28:219- Again, there is the same paucity of scientific studies combining 222. serial casting with phenol. 21. Khalili AA, Betts BB. Peripheral nerve block with phenol in the management of spasticity: indications and complications. JAMA 1967;200:1155-1157. CONCLUSION 22. Khalili AA, Harmel MH, Forster S, Benton JG. Management of spasticity by selective peripheral nerve block with dilute phenol solu- Spasticity may significantly interfere with seating and positioning. tions in clinical rehabilitation. Arch Phys Med Rehabil 1964;45:513- Severe spasticity may also interfere with hygiene, transfers, and 519. other activities of daily living. Chemical neurolysis with phenol has 23. Liversedge LA, Maher RM. Use of phenol in relief of spasticity. Br evolved into a useful technique in the treatment of spasticity. Med J 1960;2:31-33. 24. Maher RM. Relief of pain in incurable cancer. Lancet 1955;268:18-22. 25. Meelhuysen FE, Halpern D, Quast J. 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