Spasticity: Cerebral Palsy and Traumatic Brain Injury




Acknowledgment:


The authors wish to acknowledge and thank Dr. Michele Gerwin Carlson. Her efforts in the previous edition of this text provided the foundation for this chapter.


Cerebral palsy and traumatic brain injury are upper motor neuron central nervous system diseases that result in decreased function, muscle imbalances, and deformity of the upper limb. Cerebral palsy, the most common childhood motor disability, results from brain injury occurring in a fetus or infant in the perinatal period (in utero, during birth, or in infancy) or in a premature infant in whom the brain is still developing. Traumatic brain injury is secondary to intracranial masses, sequelae following surgery to treat brain lesions, infection, vascular insult, or head trauma.




Cerebral Palsy


The incidence of cerebral palsy is approximately 2 to 4 per 1000 live births. The condition is considerably more prevalent in premature infants with a very low birth weight (<3.3 pounds). The development of neonatal intensive care, and the resulting increased rates of survival of these infants, may have led to a rise in incidence of cerebral palsy. Typically thought of as an anoxic brain injury during birth, perinatal asphyxia describes a small percentage of cases. Neonatal encephalopathy, exposure to teratogens, genetic abnormalities, brain malformations, multiple births, intracranial hemorrhage, prematurity, metabolic diseases (jaundice and kernicterus), and infection have been identified as more common etiologic factors leading to the brain injury.


The classification of cerebral palsy is based on the location of the injury in the brain, number of involved extremities, level of spasticity, presence of associated movement disorders, and level of functional use. Some texts distinguish between congenital and acquired cerebral palsy based on age of onset. Spasticity, or hypertonicity, results from dysregulated reflex-arc messaging from the upper motor neurons of the medullary pyramid to the motor end plates of the limb musculature. The increased tone may be phasic or continuous and eventually results in myostatic contractures. Concomitant extrapyramidal involvement causing additional movement disorders such as dystonia, athetosis, ataxia, and flaccidity may also be present. Spastic involvement of one muscle is often coupled with flaccid involvement of its antagonist. Variable tone and muscle imbalance across limb segments result in abnormal upper limb position and function. Sensation and reflex feedback pathways are also invariably disrupted.


Cerebral palsy is considered an irreversible and nonprogressive brain injury. However, progressive muscular fibrosis, joint contracture, limb length differences, osteopenia, and atrophy occur over time. Spastic deformities in the upper extremity most often result in shoulder internal rotation, elbow flexion, forearm pronation, wrist flexion, finger flexion, intrinsic spasticity, and thumb-in-palm deformity. The age of the child at the time of the brain injury, as well as the extent and location of the cerebral involvement, is predictive of motor, sensory, and seizure involvement, as well as the child’s ultimate intelligence, coordination, and prognosis.




Traumatic Brain Injury


Traumatic brain injury is a leading cause of disability and death in the United States. An estimated 1.5 million Americans sustain a traumatic brain injury annually, and about 50,000 of these people die. Brain tumors and vascular malformations, sequelae from the surgical removal of such tumors or malformations, and infection are less common causes of traumatic brain injury. Approximately one third of traumatic brain injury survivors still require assistance with activities of daily living 1 year following injury. Most traumatic brain injuries occur in individuals who are younger (<45 years old), and those who survive have a normal life span. The enormous lifetime costs of traumatic brain injury were estimated to be $56 billion in the United States in 1995.


In traumatic accidents, falls, and abuse cases, the Glasgow Outcome Scale is frequently used to predict the outcome after brain injury. Patients with lower scores have a substantially higher incidence of severe sequelae. Age and duration of coma are also important determinants of neurologic outcome after brain injury, regardless of its severity. Brainstem involvement, as indicated by the presence of decerebrate or decorticate posturing, has a poor prognosis. Heterotopic ossification can be a complication of traumatic brain injury.


When neurologic recovery has been optimized, the brain-injured patient often has residual limb deformities, including spasticity, movement disorders, contracture, and muscle imbalance similar but not equivalent to cerebral palsy. Surgical procedures for limb deformity and dysfunction can be performed after the patient plateaus in therapy-assisted recovery. Surgery can rebalance the remaining abnormal muscle forces, correct the residual deformities, and prevent joint contractures.




Traumatic Brain Injury


Traumatic brain injury is a leading cause of disability and death in the United States. An estimated 1.5 million Americans sustain a traumatic brain injury annually, and about 50,000 of these people die. Brain tumors and vascular malformations, sequelae from the surgical removal of such tumors or malformations, and infection are less common causes of traumatic brain injury. Approximately one third of traumatic brain injury survivors still require assistance with activities of daily living 1 year following injury. Most traumatic brain injuries occur in individuals who are younger (<45 years old), and those who survive have a normal life span. The enormous lifetime costs of traumatic brain injury were estimated to be $56 billion in the United States in 1995.


In traumatic accidents, falls, and abuse cases, the Glasgow Outcome Scale is frequently used to predict the outcome after brain injury. Patients with lower scores have a substantially higher incidence of severe sequelae. Age and duration of coma are also important determinants of neurologic outcome after brain injury, regardless of its severity. Brainstem involvement, as indicated by the presence of decerebrate or decorticate posturing, has a poor prognosis. Heterotopic ossification can be a complication of traumatic brain injury.


When neurologic recovery has been optimized, the brain-injured patient often has residual limb deformities, including spasticity, movement disorders, contracture, and muscle imbalance similar but not equivalent to cerebral palsy. Surgical procedures for limb deformity and dysfunction can be performed after the patient plateaus in therapy-assisted recovery. Surgery can rebalance the remaining abnormal muscle forces, correct the residual deformities, and prevent joint contractures.




Treatment Considerations


Treatment of the upper limb in children and adults with cerebral palsy and traumatic brain injury includes surgical procedures and pharmacologic and other nonsurgical therapeutic modalities. A multidisciplinary team is necessary to manage all elements of their care. Cooperative efforts of a caregiver team and the cumulative treatment of surgeons, neurologists, and therapists result in the best outcomes. All treatment options share the goals of increasing functional use, including communication and independence with daily living, decreasing pain, managing spasticity, and prevention and correction of deformity, as well as improving hygiene or self-confidence with limb repositioning. Importantly, patients with dystonia, athetosis, poor voluntary control, and limited sensory function may be made worse by surgical intervention. However, the focus of this chapter is surgical decision making and surgical technique.


Goldner and colleagues estimated that less than 20% of children with cerebral palsy and less than 30% of children with traumatic brain injury are potential candidates for surgical procedures of the upper extremity. Surgery of the upper extremity in cerebral palsy is reparative and often palliative but not curative. Historically, only 50% of operations of the upper extremity are performed to achieve functional improvement. Treatment aimed at improving function of the upper extremity cannot restore normal limb function. Appearance concerns and hygiene are other major factors that influence treatment.


Surgery should address the entire extremity when formulating a plan. When possible, elbow, wrist, and finger flexion deformities should be corrected at the same setting ( Figure 32.1 ). This may lead to a lengthy surgery, and the surgical team should prepare for and discuss the order of each individual component in order to maximize the limited tourniquet time and minimize the anesthesia time. Correction of the elbow deformity without correction of the wrist deformity or correction of the wrist deformity without correction of the finger deformity can decrease overall function and have distressing outcomes. Studies have shown improved use of the arm in functional activities and better incorporation into daily life after well-timed and well-planned upper extremity surgery has been performed. A detailed evaluation combined with appropriate patient selection and careful decision making will reliably provide positive treatment outcomes.




FIGURE 32.1


Concurrent correction of elbow and wrist flexion deformities is important to improve limb function. A, Wrist and elbow flexion deformity. B, Correction of the elbow alone leaves the wrist flexed. C, Correction of the wrist alone does not improve the patient’s ability to position the hand in space. D, Correction of the wrist and elbow places the hand in a neutral position with maximal reach.


Evaluation


A careful and thorough examination of each patient is mandatory. The evaluation should include the patient’s underlying disease, developmental stage, intellectual aptitude, motor function, and sensibility. The patient’s ability to access therapy and support resources is equally important. An inventory of the patient’s provider team is required (e.g., parents, caregiver, pediatrician, neurologist, occupational therapist, physical therapist, social worker). Surgical results will not be optimized unless the patient is able to obtain therapy, maintain hygiene, and obtain accommodations at home and in school. In addition, an essential component of the evaluation is to exclude other treatable diagnoses for cerebral dysfunction and to determine if the disorder is progressive. Multiple visits and examinations are required to accurately appreciate the extent of a movement disorder and to fully determine all the prognostic factors.


Evaluation of a patient with spasticity must include an accurate assessment and a documented list of treatment expectations. Asking the patient and/or caregiver what they expect to achieve is mandatory to avoid unrealistic hopes. The Canadian Occupational Performance Measure (COPM) and Goal Attainment Scaling are unlike other standardized patient-reported outcome instruments due to the individualized approach used to establish goals. The COPM capitalizes on a semistructured interview that reflects the usual interaction between an occupational therapist, who approaches practice from a client-centered framework, and his or her client. Through this interview, parents and children identify performance activities that are perceived as important by the parent, child, and/or society; performance is rated on a scale between 0 (cannot do) and 10 (can do very well), and the activities are used to establish goals for treatment. Scores between baseline and reassessment are calculated to evaluate outcomes of treatment. Although individuals may differ in their ideas of what constitutes successful outcomes, research suggests that a change of two or more points reflects meaningful change.


It is important to identify patients who have little voluntary control, marked dystonia, or limited sensibility because these individuals will obtain limited functional benefit from surgical intervention. A simple interview of the patient (and the parent or caregivers) can elicit the activities that the patient can and cannot perform with the spastic extremity, but other procedures are also valuable in individualizing treatment, such as prognostic testing, including functional scores, video analysis, electromyography, and imaging studies. Carlson and associates found that reviewing the videotape compared to the office visit examination will change the operative plan in 75% of patients.


Evaluation is particularly challenging in nonverbal patients, families with language barriers, and young patients. In cerebral palsy, upper limb dysfunction is usually noted by 1 year of age, as the infant fails to obtain normal developmental milestones, such as crawling, pulling to stand, passing objects from hand to hand, or a developing oppositional pinch. Infants may develop a more primitive key pinch (thumb to side of index finger) versus oppositional pinch. Maintenance of primitive reflexes also reflects a central nervous system disease process.


Physical Examination


Physical examination of the spastic upper extremity is chal­lenging and requires experience, a relaxed clinical atmosphere, multiple office visits, and a team approach. Recognition of contraindications to surgery and predictors of poor outcome via the physical examination directs treatment decision making. Despite their best intentions, patients often have difficulty cooperating during the examination. Asking patients to perform activities with both extremities can ensure that they comprehend instructions, even if they can only perform the task with one. Each extremity should be evaluated separately and any mirror movements noted. Although spastic deformities in the upper extremity most often result in shoulder internal rotation, elbow flexion, forearm pronation, wrist flexion, finger flexion, intrinsic spasticity, and thumb-in-palm deformity ( Figure 32.2 ), many variations exist.




FIGURE 32.2


Spastic posturing in the upper extremity. A and B, Shoulder internal rotation, elbow flexion, forearm pronation, and thumb in palm and fist with active wrist extension. C and D, Wrist flexion and ulnar deviation with finger swan neck deformities.

(Courtesy of Shriners Hospital, Philadelphia, and Children’s Hospital, Los Angeles.)


The examination must accomplish several tasks that serve as clinical guidelines. The surgeon’s examination begins with casual conversation, such as asking the patient his or her age and assessing caregivers. The resting position of the limbs should be noted. Ask the patient and/or caregivers exactly why they are seeing a surgeon and identify treatment goals. If age and intelligence are appropriate, ask the child to perform active movements such as hands over the head, hands from knee to mouth, elbow flexion and extension, supination and pronation, open and closing of the hands, and clapping. Passive range of motion of all joints is then measured. The muscle strength of all involved and the potential donor muscles for transfer are measured. Hyperreflexia and clonus are noted. Patterned hand function, as well as muscle spasticity and contracture, are identified. Spasticity must be distinguished from muscle and/or joint contracture. When relaxed, patients with muscle spasticity demonstrate full passive range of motion of an affected joint, whereas in those with muscle or joint contracture the passive movement remains limited. Muscle contracture and joint contracture often coexist in older or skeletally mature patients; joint contracture is less common in younger children. Muscle spasticity can be overcome by applying gentle sustained resistance to the spastic force. Several grading systems for spasticity exist, such as the Modified Tardieu Scale and Modified Ashworth Scale ( Table 32.1 ). Inspection for potential hygiene problems should include the axilla, antecubital fossa, volar wrist flexion crease, palm, and interdigital spaces.



TABLE 32.1

Modified Tardieu Scale and Modified Modified Ashworth Scale




























Grade Modified Tardieu Scale Modified Modified Ashworth Scale
0 No resistance to passive ROM No increase in muscle tone with passive ROM
1 Slight resistance with no clear catch Slight increase in tone; catch and release or minimal resistance with ROM
2 Clear catch at precise angle, halting passive ROM, followed by release Marked increase in muscle tone, catch in middle range, and resistance through remainder of ROM, still easily moved
3 Fatigable clonus (<10 seconds with resistance) occurring at precise angle Considerable increase in muscle tone, passive movement is difficult
4 Infatiguable clonus (>10 seconds) Rigid in flexion or extension

ROM , Range of motion.


Spasticity is classically classified by the number of limbs involved: monoplegia (one extremity), hemiplegia (one arm, one leg), diplegia (two legs), triplegia (two legs, one arm), and quadriplegia (all four extremities). Motor function is also classified as spastic, flaccid, and athetoid ( ). Many patients have a combination of movement patterns. Spastic involvement of a muscle is often coupled with flaccid involvement of its antagonist, potentiating the deformity from imbalance. The surgeon should observe the patient for underlying movement disorders, especially dystonia. Dystonia is defined as “involuntary sustained or intermittent muscle contractions causing twisting and repetitive movements, abnormal postures or both.” Hypotonic, hypertonic, hyperkinetic, and mixed tone movement disorders should also be noted and are known to correlate with poorer surgical outcomes.


In addition to motor assessment, intellectual capacity and sensory function also correlate with severity and surgical outcomes in children with cerebral palsy and traumatic brain injury. In the cooperative child, stereognosis is easily tested with two or three simple objects such as a coin, poker chip, paperclip, or key in each hand. The hand position and function may alter one’s ability to perform sensory testing. The child’s intellectual or cognitive impairments are harder to assess in an office visit; asking the child to follow voluntary commands or perform tasks such as placing the hand to the mouth and noting the child’s school level or integration into a normal or specialized classroom are ways of establishing a baseline.


A standardized task performance evaluation can assist in quantifying the severity of impairment and in identifying patterns of hand function. The House Classification and the Manual Ability Classification System describe how children with cerebral palsy use their hands to handle objects in daily activities and reflect the child’s typical performance ( Tables 32.2 and 32.3 ). Videotaping or functionally evaluating the patient performing routine activities or using scored functional tests (e.g., Jebsen-Taylor hand function test, box and blocks test, pegboard test) may be helpful, although the child may perform well for the surgeon but use different functions at home or when unobserved. Other validated evaluation tools, including the Modified (Modified) Ashworth Scale, Modified Tardieu Scale, Melbourne Assessment of Unilateral Upper Limb Function, Quality of Upper Extremity Skills Test, Shriners Hospital Upper Extremity Evaluation, and Assisting Hand Assessment, can grade upper extremity disability and guide treatment. Many other instruments have been designed to quantify parent and child self-assessment of upper extremity function in children with cerebral palsy. The correlation of three-dimensional motion analysis is still being studied as a prognostic and classification tool.



TABLE 32.2

Manual Ability Classification System (MACS) of Hand Function






















Level Description
I Handles objects easily and successfully
II Handles most objects but with somewhat reduced quality and/or speed of achievement
III Handles objects with difficulty; needs help to prepare and/or modify activities
IV Handles a limited selection of easily managed objects in adapted situations
V Does not handle objects and has severely limited ability to perform even simple actions


TABLE 32.3

House Classification of Hand Function












































Score Designation Activity Level
0 Does not use Does not use
1 Poor passive assist Uses as stabilizing weight only
2 Fair passive assist Can hold onto object placed in hand
3 Good passive assist Can hold object and stabilize for use by other hand
4 Poor active assist Can actively grasp object and hold it weakly
5 Fair active assist Can actively grasp object and stabilize it well
6 Good active assist Can actively grasp object, stabilize it well, and manipulate it against other hand
7 Spontaneous use, partial Can perform bimanual activities easily; occasionally uses hand spontaneously
8 Spontaneous use, complete Uses hand completely independently, without reference to other hand


Physical Examination Key Points and Clinical Guidelines


Shoulder.


The most common position of rest of the shoulder in a patient with spasticity is internal rotation. Internal rotation and adduction posturing of the shoulder is caused mainly by spasticity and/or contracture of the subscapularis and pectoralis major muscles. The latissimus dorsi and teres major muscles can also contribute. Over time, glenohumeral dysplasia, capsular contracture, and thickening of the surrounding fascia add to the deformity. Less frequently, a severe external rotation and abduction posture of the shoulder occurs secondary to spasticity or contracture of the rotator cuff muscles ( Figure 32.3 ). The physician must determine whether the limitations in shoulder motion interfere with the patient’s ability to position the hand in space for function.




FIGURE 32.3


External rotation and abduction posturing of the shoulder is rare and significantly limits function.

(Copyright © Michelle Gerwin Carlson.)


Elbow.


The physician may observe dynamic elbow position when the patient is walking, running, and performing activities with the contralateral extremity. The predominant elbow spastic deformity is flexion. The initial cause is related to spasticity or contracture of any or all of the elbow flexors (biceps, brachialis, brachioradialis). Long-standing deformities can also result in soft tissue and joint contractures. The severity of the flexion deformity is variable. Some patients have only dynamic posturing (involuntary flexion with walking or effort) or a smidge of elbow contracture. Other patients have severe hyperflexion with antecubital skin breakdown and intertriginous infections.


Traditionally, an elbow flexion contracture was considered mostly an aesthetic or hygienic problem ; however, even mild dynamic posturing or contracture can be problematic for the patient and family. Appearance is an important factor, especially for hemiplegic patients, and correction is commonly requested. In contrast, a substantial flexion deformity interferes with activities of daily living and leads to skin breakdown in the antecubital fossa. Lessening a severe contracture can allow a patient to use the forearms to assist in wheelchair transfers, touch a picture board or use technology to communicate, reach the tray top of a wheelchair, or touch a wider sphere of objects in his or her environment (increase in workable reach space). In less severe flexion deformities, release of the contracture can allow for the use of crutches or walkers, facilitate two-handed manipulation of objects away from the body, and increase independence with activities of daily living.


Forearm.


Pronation positioning of the forearm is mainly caused by spasticity of the pronator teres. The position is initially passively correctable; however, a fixed deformity occurs over time secondary to contracture of the interosseous membrane or disruption of the radioulnar joint(s). Pronation deformity may interfere with bimanual use of the extremity in two-handed manipulation of objects (e.g., carrying a tray). With a pronation contracture, the palms cannot face each other and the manipulation of small objects between the hands is also difficult. With severe spasticity, patients are forced to assume a reverse grasp posture, using the ulnar aspect of the hand to grasp objects, because they are unable to present the radial aspect of the hand. Internal rotation contracture of the shoulder exacerbates the pronation deformity as the shoulder is unable to compensate. Rarely, radial head dislocation (in 2% of patients) or distal radioulnar joint dislocation may occur and further limit the passive range of motion of the forearm.


Palpate the pronator teres during passive supination of the forearm to identify spasticity. Evaluate active supination, pronation, and the position of the forearm at rest. Examine the distal and proximal radioulnar joint for dislocation, subluxation, or instability. Palpate for the radial head in supination and pronation and determine radial head alignment. During task performance, determine if forearm rotation is adequate for workspace, midline, and overall task performance.


Wrist and Digits.


The wrist often assumes a flexed posture. There are several potential causes, including weak wrist extensors, tight or spastic wrist flexors, and volar wrist capsular contracture. The flexed attitude of the wrist causes several functional problems. Wrist flexion weakens grip secondary to the decreased mechanical advantage of the digital flexors and shift of the length-tension curve. Severe contractures can lead to hygiene issues.


Observation of wrist position during hand use is critical to assess object acquisition and release. The physician can also determine patterns of usage and assess spastic muscles. For example, if the wrist deviates in an ulnar direction with flexion, spasticity of the flexor carpi ulnaris (FCU) is likely. Circumduction during attempted wrist extension implies that the patient is using the extensor carpi ulnaris (ECU) to augment wrist extension. Passive wrist motion should be measured and recorded. Incomplete passive extension implies contracture of the wrist flexors or even the radiocarpal joint. The muscles about the wrist should be palpated during active movement. An assessment of spastic muscles and/or those muscles firing excessively should be determined. For example, firing of the FCU or the flexor carpi radialis (FCR) during digital opening implies spasticity or an exaggerated response to facilitate digital opening.


The Volkmann angle is commonly used to assess digital flexor tendon tightness as it might be used in a patient with compartment syndrome ( Figure 32.4 ). The angle is measured with the wrist flexed and the digits held completely extended; the wrist is passively brought into maximal extension. In the absence of flexor tendon tightness, composite full wrist extension and finger extension can be achieved. With digital flexor contracture, the wrist cannot be extended to neutral without flexion of the digits. Subsequently, one can assess whether the flexor digitorum superficialis (FDS) or flexor digitorum profundus (FDP) is spastic by holding the wrist in extension while passively extending the digits. When passive proximal interphalangeal (PIP) joint extension is limited, FDS spasticity should be suspected (FDP spasticity may also be present). If the PIP joints have full passive extension but the distal interphalangeal (DIP) joints remain flexed, FDP spasticity should be suspected.




FIGURE 32.4


Volkmann test for digital flexor tendon tightness. A, The digits are held extended with the wrist flexed. B, The wrist is extended with the digits extended. With no flexor tendon tightness, full extension of the wrist should be possible. Wrist extension to less than neutral (Volkmann angle) indicates the need for surgical intervention.


Evaluate a patient’s grasp and release ability with the wrist flexed and extended ( ). Poor grasp is often secondary to weak or absent wrist extension, because a flexed wrist slackens the digital flexor muscles and minimizes the potential for force production. Inability to extend the wrist may be caused by weak or absent wrist extensors or by spastic wrist flexors. The strength of grasp can be improved with a tendon transfer to increase wrist extensor power. Poor release is the result of weak or absent digital extensors. Patients with impaired release are unable to actively extend the digits or are only able to extend the digits when the wrist is flexed. When the wrist is passively held in extension, active digital extension is impossible. An isolated transfer to improve wrist extension in this case is contraindicated as the patient will be unable to extend the digits for object acquisition. The physician could consider a series of tendon transfers to augment wrist and digital extension.


Intrinsic muscle tightness leads to a resting position of metacarpophalangeal (MP) joint flexion and interphalangeal (IP) joint extension. When a patient with intrinsic tightness attempts digital extension, the MP joints periodically flex. If a patient is a candidate for digital flexor tendon lengthening, the intrinsic muscles must be carefully examined. If the intrinsics are spastic, release of the digital flexors without release of the intrinsics will result in a hand with flexed MP joints and extended PIP joints. Intrinsic tightness is best evaluated by the Bunnell test, which is performed by passive flexion of the PIP joints while the MP joints are held sequentially in full extension and in flexion. When fixed intrinsic tightness is present, passive motion of the PIP joint is greater with the MP joints flexed than when extended. This test should be performed in wrist flexion because if the digital flexors are tight, they can overpower the intrinsic muscles. If swan neck deformities of the PIP joints are present, they should be evaluated for cause and flexibility. Extrinsic extensor tendon over pull or intrinsic muscle spasticity can yield swan neck deformities. Local anesthetic block of the ulnar nerve at the wrist can be an effective way to demonstrate (both to the surgeon and the patient) the effect of intrinsic muscle release. Ulnar nerve block can also help differentiate intrinsic spasticity from fixed intrinsic or PIP contractures.


Thumb.


The thumb-in-palm deformity is a challenging problem to rectify. Correction of the thumb-in-palm deformity is a careful balancing act among multiple muscles, tendons, and joints. Correction of the thumb-in-palm deformity is often performed concurrently with tendon transfer surgery to augment wrist extension. Hence, testing of the thumb-in-palm deformity should be done in wrist flexion and extension. Thumb extension occurs in a radial direction in the plane of the hand, and thumb abduction occurs in the plane perpendicular to the palmar surface ( Figure 32.5 ). The adequacy of the first web space should be assessed with measurements of the passive and active web space angle. The muscles about the thumb should be assessed for spasticity or contracture, including the adductor pollicis brevis (APB), flexor pollicis brevis (FPB), first dorsal interosseous, flexor pollicis longus (FPL), abductor pollicis longus (APL), extensor pollicis brevis (EPB), and extensor pollicis longus (EPL). In addition, the thumb should be evaluated for hyperextension at the MP joint and volar plate laxity.




FIGURE 32.5


A and B, Dynamic thumb-in-palm deformities flexion into the palm with digit extension and interfere with grasp and prevent the manipulation of large objects. C and D, Severe thumb contracture with fixed joint degenerative changes and skin and soft tissue contracture.

( A, Copyright Michelle Gerwin Carlson. C and D, Reproduced with permission of Children’s Orthopaedic Center, Los Angeles.)


Diagnostic Testing


Imaging


There is a limited role for imaging in the treatment of patients with cerebral palsy or traumatic brain injury. Documenting joint subluxation or frank dislocation, especially of the radial head and distal ulna, may explain bony blocks to joint motion. Degenerative changes, fracture, infection, avascular necrosis, or concurrent congenital musculoskeletal disease may also be identified on imaging. Functional brain magnetic resonance imaging has been studied as an accurate predictor of upper extremity function in upper motor neuron disease and a useful outcomes measurement tool to document cortical reorganization after treatment.


Electromyography


Dynamic electromyography can be helpful in identifying spastic and flaccid muscles and determining phasic activity. Electromyography has been advocated in the decision-making process for surgery, although some believe that the information gained is no more valuable than that obtained from serial physical examinations. Dynamic electromyography often requires a combination of surface electrodes and fine-wire examination of the deeper muscles of the elbow, forearm, and hand. Volitional activity as well as patterned activity should be evaluated to identify muscles that are firing normally in phase versus those that are firing out of phase, firing continuously, or not firing at all ( Figure 32.6 ).




FIGURE 32.6


Dynamic electromyograms of the elbow. A, Normal phasic control in maximal contraction. Note the alternation in firing between flexion and extension. B, In this patient there is loss of phasic control, and the elbow flexors fire in flexion and extension. C, Normal functional use. A patient is asked to lift a light object, and the amount of contraction decreases from maximal effort (compare with A ). D, In this patient there is loss of functional grading, because even when the patient lifts a light object, there is almost maximal contraction. BR , Brachioradialis; Flex, flexion; Ext, extension.


In the elbow, the biceps, brachialis, and brachioradialis can be evaluated by electromyography for spasticity and possible surgical release. Similarly, the adductor pollicis muscle can be assessed to determine its role in thumb-in-palm deformity. Weak or absent wrist extension to produce grasp or digital extension to yield release can be accessed via electromyographic response of the wrist extensors or digital flexor muscles, respectively. Dynamic electromyography can help identify inappropriate muscle firing, as well as those muscles that would be best for transfer. Out-of-phase or continuous firing of the FCU and digital flexors is frequently seen; this characteristic makes them poor donors for transfer. Activity of the digital and radial wrist extensors is often absent on electromyographic studies. The ECU findings are more variable.


Muscles firing during digital release are good candidates for transfers to improve digital extension, and those firing in grasp are good choices for wrist extension transfers. The FCU, FCR, brachioradialis, pronator teres, ECU, and extensor carpi radialis longus (ECRL) can all be studied to determine which muscles are active in grasp and which muscles are active in release. Continuous activity in a muscle is a relative, although not absolute, contraindication for transfer, because some data suggest that phasic activity can develop after transfer.


Specially trained personnel are required to perform dynamic electromyographic tests, and many laboratories do not have this technical support. In addition, in the lower extremity, electromyography has been shown to alter performance due to discomfort. The overall applicability of upper extremity dynamic electromyography remains questionable.




Nonoperative Management


Therapy


The role of nonoperative management in the treatment of cerebral palsy and traumatic brain injury cannot be overemphasized. The therapists play a critical role in the treatment paradigm and in the education of the patient and caregiver. Therapeutic intervention includes passive range-of-motion movements, splint fabrication, and implementation of adaptive strategies and devices. Passive range-of-motion movements and splinting are instituted to maintain supple joint structures and prevent fixed contractures. The therapist must be skilled in splint fabrication because the limbs are prone to skin breakdown secondary to spasticity and altered sensibility. In fact, severe spasticity is a contraindication to splint fabrication because “rebound” spasticity ( Figure 32.7 ) can lead to skin breakdown.




FIGURE 32.7


Splinting of the severely flexed wrist is difficult. Volar splinting of the wrist stimulates the palm, increasing the pathologic flexion response, which tends to make the patient “flex out” of the splint. Dorsal splinting is mechanically ineffective.

(Copyright Michelle Gerwin Carlson.)


The therapist has a critical role in eliciting active movement and encouraging usage of the spastic limb. Incorporation of the spastic limb into daily activity is a challenging problem, especially in hemiplegia. Hemiplegic patients can perform tasks more easily, faster, and with more spontaneity with the uninvolved limb. The spastic hand is often dubbed the “helper hand.” Nonetheless, active usage promotes activity within the sensorimotor cortex homunculus dedicated to the hand and is necessary to maintain these pathways. In the pediatric population, therapists will use play as a means of promoting limb usage. Grasping and manipulation of objects of different sizes and shapes are used to promote different prehension patterns. Constraint-induced movement therapy forces the use of the affected side by restraining the unaffected side. The constraint can be holding the uninvolved limb and allowing prehension only with the affected side. The constraint also can be more restricting, such as splinting or casting of the unaffected side. Electrical stimulation of weak or neglected muscles combined with therapy may also provide additional benefits.


The therapist also plays a role as an educator with respect to diagnosis and treatment and comprehension of the child’s future level of independence, intellectual ability, and other abilities. In cerebral palsy, the parents are often overwhelmed and are searching for answers. A skilled therapist can answer most of the questions and defer to the physician with queries regarding surgical management. The parents do need to mourn the “loss of the perfect child,” and grieving is a necessity. Some parents are unable to cope with the added burden and should be referred to a psychiatrist, psychologist, or other mental health provider. In traumatic brain injury, the psychological burden can be overwhelming for both the patient and the caregiver; psychotherapy can be beneficial in handling the added stress.


The therapist also plays a critical role following surgery. Therapy protocols are established for tendon lengthenings, muscle releases, and tendon transfers. These involve three stages: immobilization, mobilization, and incorporation. A skilled therapist will maximize the outcome.


Medical Management


Medical management may include injectables, orals, or implantable intrathecal devices. Muscle relaxants such as benzodiaza­penes and baclofen, as well as antiseizure medications, have a clear role in management of limb function and position but are rarely managed by the surgeon.


Botulinum Toxin


Botulinum toxin (Botox®) is a useful adjunctive treatment for spasticity. Botulinum toxin type A blocks the release of acetylcholine at the presynaptic neuromuscular junction, which temporarily weakens the injected muscle. When used in the appropriate dosage and carefully injected, botulinum toxin has a high safety profile. A maximum total dose of 10 U/kg is given. The use of botulinum toxin for spasticity is off-label and should be discussed with the patient and caregiver beforehand.


The indications for botulinum toxin injection are variable depending upon the patient and reasoning. Botulinum toxin can be injected to temporarily decrease spasticity and allow more intense therapy to resolve any tightness. For example, children with cerebral palsy can have some increased spasticity and tightness during periods of rapid growth. Botulinum toxin injection can lessen the tightness and resolve any impending contracture. Botulinum toxin can also be used to assess and forecast the effect of lengthening a muscle-tendon unit. This assessment may prevent surgery that would not be beneficial and/or would result in diminished function.


Authors’ Preferred Technique for Botulinum Toxin Injection


Botulinum toxin injection is performed in the clinic or the operating room, depending on the age of the patient and muscle(s) to be injected. Older patients and superficial muscles can be injected after the application of topical lidocaine cream or use of a ShotBlocker (Bionix Development Corporation, Toledo, OH). Younger patients and deeper muscles may require sedation or anesthesia. Deeper muscles can require electrical stimulation or ultrasound to verify appropriate needle placement. Botulinum toxin is prepared by diluting it with preservative-free saline. An insulated needle connected to an electrical stimulation unit or under direct ultrasound observation is inserted into the target muscle. Placement within the correct muscle is verified by stimulation prior to injection.


The protocol following injection varies with the indication. For patients with increasing tightness, a cast is applied for 3 week to maximize the stretch. For patients who require functional assessment, no daytime immobilization is required.




Operative Management


Shoulder


Types of Operative Procedures


A spastic shoulder that does not respond to therapy and botulinum toxin is typically treated by lengthening or release of the tight muscles. Tendon transfers about the shoulder for cerebral palsy or traumatic brain injury have not been effective. In severe cases, humeral osteotomy can reposition the limb in space. In athetoid patients, recurrent dislocation of the glenohumeral joint should be treated with glenohumeral arthrodesis.


An inventory of the patient’s spastic muscles will direct surgical management. Typically, the subscapularis and pectoralis major muscles are the major culprits and must be lengthened to lessen the internal rotation and adduction contracture. Less commonly, the latissimus dorsi and teres major muscles are released at the same time. External rotation spasticity can also be relieved by release of the supraspinatus, infraspinatus, and teres minor. Patients with severe external rotation spasticity are unable to maneuver through a doorway. Internal rotational humeral osteotomies may be required to improve wheelchair positioning.


Soft Tissue Release of Shoulder Internal Rotation Deformity


Indications.


Mild axillary hygiene access or dynamic shoulder contracture can usually be treated with stretching. Failed nonoperative treatment and recurrent axillary hygiene issues or inability of a patient to position a functional hand in space are indications for surgery.


Contraindications.


Release of the internal rotators should not be performed in patients with subluxation or dislocation of the shoulder, because this may exacerbate the instability. These patients are better candidates for shoulder fusion. A relative contraindication to soft tissue surgery is weak external shoulder rotators. Contracture will recur soon after surgery if range of motion is not maintained by therapy and strengthening of opposing muscles.


Preoperative Planning.


Careful clinical examination of the muscles while the patient is awake is necessary to determine whether the shoulder muscle involvement is dynamic or passive. Once the patient is asleep, passive contractures can be detected. Preoperative imaging should be considered if glenohumeral subluxation, dislocation, or degenerative disease is suspected.


Technique.


An axillary or deltopectoral incision is made in the anterior aspect of the shoulder. The tendon of the pectoralis major is identified along the posterior surface of the muscle. Fractional lengthening is performed by cutting the tendon at its musculotendinous junction. The deltopectoral interval is further divided to expose the underlying subscapularis. The subscapularis tendon insertion is identified as it inserts on the lesser tuberosity and is divided or “Z”-lengthened. A “Z”-lengthening is preferred primarily because it preserves some function of the tendon, prevents excessive external rotation posture, and helps prevent anterior dislocation of the shoulder. Subscapularis lengthening can also be accomplished using muscle slide through a longitudinal incision along the lateral border of the scapula. The subscapularis is elevated in an extraperiosteal plane from the anterior surface of the scapula beginning inferiorly and progressing superiorly. The shoulder joint does not need to be opened unless one is performing a glenohumeral fusion. An external rotation abduction splint or shoulder spica cast is worn for 4 to 6 weeks, followed by range-of-motion exercises.


Rotation Osteotomy of the Humerus


Indications.


An extremely contracted shoulder may not be amenable to soft tissue release. Humeral osteotomy can reposition the limb in space and enhance function. Humeral osteotomy will not address axillary hygiene issues.


Contraindications.


Poor hand function is a relative contraindication to humeral osteotomy. However, concomitant surgery to improve hand function can be performed at the same setting.


Preoperative Planning.


The amount of external rotation to improve function needs to be determined prior to surgery. A skilled therapist is invaluable to ensure the correct amount of rotation necessary. The right amount of rotation will enhance external rotation activities and preserve internal rotation and midline functions.


Technique.


A medial, lateral, or deltopectoral approach can be used. We prefer the medial approach for numerous reasons. First, the approach is straightforward and goes between the median and ulnar nerves. Second, the configuration of the medial humerus is suitable for plate and screw fixation. Third, the arm rests directly on the arm table after osteotomy, which facilitates fixation. Last, the medial incision heals nicely and is well concealed.


No tourniquet is used. The planned incision is infiltrated with bupivacaine and epinephrine prior to prepping and draping. A medial incision is made overlying the intermuscular septum and midshaft of the humerus. The superficial nerves are protected. The intermuscular septum is identified and excised. The ulnar nerve is retracted in a posterior direction while the median nerve and brachial artery are retracted in an anterior direction. The diaphysis of the humerus is exposed.


A 6- to 8-hole plate is chosen for fixation. The size depends on the girth of the humerus; usually, 3.5 mm is sufficient in an adolescent or adult. The plate is placed over the humerus and the proximal 3-4 bicortical screws are placed through the plate and humerus. The periosteum is not incised along the entire humerus but only over the osteotomy site ( Figure 32.8, A ). Prior to performing the osteotomy, a Kirschner wire is placed in the distal fragment to mark the amount of desired correction. The wire is placed in line with a hole in the plate. The plate is removed and the humeral osteotomy performed using an oscillating saw; during the procedure, irrigation is necessary to minimize thermal necrosis. Following completion of the osteotomy, the humerus is rotated so that the screw holes and Kirschner wire are aligned. The wire is passing through a hole in the plate. By means of the predrilled screw holes, the plate is affixed to the proximal fragment. The osteotomy is reduced and the distal fragment is secured with screws using standard compression techniques (see Figure 32.8, B ).




FIGURE 32.8


A, A Kirschner wire is drilled in an oblique angle to simulate the amount of correction, and a fine bladed saw is used for osteotomy. B, The humerus is externally rotated, the osteotomy is reduced, and the plate and screws are applied.

(Courtesy of Shriners Hospital for Children, Philadelphia.)


Following surgery, a large bulky dressing is applied from the hand to the axilla. No splint is used; however, a sling must be worn to prevent stress across the osteotomy site. The dressings are removed and a humeral brace is fabricated 3 weeks after surgery. The brace is worn for about 1 month until radiographic and clinical union is evident.


Glenohumeral Joint Arthrodesis


Indications.


Instability or painful glenohumeral joint subluxation is the main indication for arthrodesis.


Contraindications.


Absent scapular control is a contraindication for shoulder fusion. The patient must have ample parascapular muscles to control the fused glenohumeral joint.


Preoperative Planning.


The goal is to determine the optimal position for fusion. The standard position is 30 degrees of abduction, 30 degrees of internal rotation, and 30 degrees of forward flexion ( Figure 32.9, A ). The position may vary, however, in the impaired patient, depending on the patient’s function and overall needs.




FIGURE 32.9


A, Glenohumeral arthrodesis using dual-plate fixation. B, Shoulder is positioned in 30 degrees of abduction, 30 degrees of internal rotation, and 30 degrees of forward flexion to allow hand-to-mouth activity.

(Courtesy of Shriners Hospital for Children, Philadelphia.)


Technique.


Numerous operative techniques have been described to achieve union. An extended deltopectoral approach provides wide exposure to the glenohumeral joint. The articular cartilage is removed from the humeral head and glenoid. Exposed cancellous bone is mandatory for union. Rigid internal fixation is preferred, using dual plate fixation (see Figure 32.9, B ). One plate is placed across the scapular spine and onto the lateral humerus. A second plate is secured across the acromion and onto the humerus. Additional fixation can be obtained with large cancellous screws from the lateral humerus into the glenoid. Bone graft may be added to further promote healing. Postoperative immobilization varies from an abduction pillow to a shoulder spica cast, depending on the quality of the bone and rigidity of the fixation.


Authors’ Preferred Method of Treatment


Nonoperative management is the mainstay of treatment for shoulder spasticity. Spasticity and/or contractures that do not respond to stretching and botulinum toxin can be treated with surgery. An inventory of the potential spastic muscles is delineated by repeated physical examinations.


Moderate spasticity and contracture are treated by length­ening of the spastic and tight muscles. Lengthening of the subscapularis and pectoralis major is preferred to prevent overcorrection. Pectoralis major lengthening is performed by fractional lengthening of the muscle-tendon junction. Subscapularis lengthening is accomplished via “Z”-lengthening using a deltopectoral approach or muscle slide through a longitudinal incision along the lateral border of the scapula. The subscapularis is elevated in an extraperiosteal plane from the anterior surface of the scapula beginning inferiorly and progressing superiorly.


If the latissimus dorsi and teres major muscles are spastic offenders, their tendons are released from the insertion on the humerus.


Severe contracture and limb malposition are treated by humeral osteotomy, with the caveat that axillary hygiene will not be altered. Glenohumeral joint arthrodesis is reserved for instability or painful glenohumeral joint subluxation.


Elbow


Types of Operative Procedures


Spastic dynamic elbow flexion contractures can be surgically addressed by denervation, lengthening, or myotomy of the muscles crossing the anterior aspect of the elbow. Muscle contracture release options include either individual lengthening or release of the biceps, brachialis, and/or brachioradialis. In addition, the flexor-pronator mass may be a contributor to the elbow flexion contracture. A concomitant flexor-pronator slide may be necessary.


Fixed, long-standing contractures result in additional skin, soft tissue, and joint factors. Release requires more extensive surgery, including skin “Z”-plasty and possible capsular release; the rate-limiting factor is often the stretch of neurovascular structures. Therefore, we try to avoid capsular procedures but favor serial casting following surgical lengthening and/or release of the skin, fascia, and muscles to make additional gains in elbow extension.


Musculocutaneous Neurectomy


Indications.


Musculocutaneous neurectomy is rarely performed. Neurectomy is reportedly effective for spastic deformity of less than 30 degrees. Neurectomy denervates the biceps and brachialis and results in active elbow flexion through the remaining brachioradialis. Full passive range of motion of the joint is necessary because this procedure does not correct contractures about the joint.


Contraindications.


Musculocutaneous neurectomy is an “all-or-none” treatment, and no fine-tuning of tension in the muscles or separate biceps or brachialis release is possible. This may explain its decline in usage. It is contraindicated in patients with functional elbows that bring the hand into positions necessary for activities of daily living. Neurectomy addresses only muscular spasticity and is contraindicated when fixed contracture exists. Additionally, musculocutaneous neurectomy results in a sensory deficit in the lateral arm in the distribution of the lateral antebrachial cutaneous nerve. Neurectomy of only the motor branches preserves this sensibility.


Preoperative Planning.


Preoperative lidocaine or bupivacaine block of the musculocutaneous nerve along the proximal medial aspect of the biceps is often performed prior to formal neurectomy. The temporary paralysis assists in differentiating the contribution of abnormal muscle tone from fixed contracture and helps predict the results following neurectomy. The block also identifies the amount of elbow flexion possible through the brachioradialis muscle. A preoperative dynamic electromyogram (surface or fine wire) may also be helpful in determining patterns of spasticity.


Technique.


The musculocutaneous nerve is exposed through an axillary or medial arm incision. The musculocutaneous nerve is identified emanating from the lateral cord of the brachial plexus. Stimulation yields elbow flexion and confirms identification. A 1-cm segment of musculocutaneous nerve can be removed; however, isolation and resection of the motor braches are preferred. No postoperative immobilization is necessary.


Elbow Flexor Lengthenings for Dynamic Spasticity


Indications.


Lengthening or release of the biceps, brachialis, and brachioradialis is a direct approach to spastic flexion contracture of the elbow. The procedure can increase elbow active extension by about 40 degrees, with minimal loss of flexion arc or functional flexion power.


Contraindications.


Contraindications to isolated lengthenings include skin, capsular, and joint contractures. Patients must have strong active elbow flexion preoperatively, or lengthening of the flexors may weaken the elbow and negate hand-to-mouth activities.


Preoperative Planning.


Serial clinical examinations are necessary to properly identify the muscles that require lengthening. Results of previous treatments, including passive stretch therapy, splinting/casting, and botulism toxin injections, are useful in predicting the outcome and guiding surgical planning. Dynamic electromyography may again be helpful to distinguish the contributions of individual muscles to the deformity.


Technique.


The patient is placed supine on the operating room table. The entire extremity is prepped and draped. A sterile circular tourniquet is applied (HemaClear, OHK Medical Devices, Grandville, MI) that exsanguinates during application. For purely dynamic spasticity, a transverse incision across the antecubital fossa is made. Antecubital veins are mobilized or ligated. The lateral antebrachial cutaneous nerve, emerging from the interval between the biceps and brachialis lateral to the biceps tendon, is identified and retracted laterally. The lacertus fibrosus is identified and the median nerve and brachial artery are appreciated deep to the lacertus fibrosus. The radial nerve is isolated between the brachioradialis and brachialis muscles.


The brachioradialis is usually treated by myotomy. The muscle is isolated from the extensor carpi radialis brevis (ECRB) and the radial nerve. The muscle is cut using electrocautery for complete release. Deep to the biceps tendon, the brachialis muscle-tendon junction is identified. A fractional lengthening is performed by cutting the tendon, leaving the muscle alone ( Figure 32.10 ). The biceps may or may not be lengthened depending upon the preoperative examination for spasticity and its contribution to forearm supination. The decision is not always straightforward. If the biceps is lengthened, a fractional lengthening is performed at the muscle-tendon junction.




FIGURE 32.10


Fractional lengthening of the elbow flexors. A, Through a transverse incision in the antecubital fossa, the lacertus fibrosus is transected, and the neurovascular bundle and lateral antebrachial cutaneous nerves are identified and protected. B, “Z”-lengthening of the biceps tendon with medial and lateral tenotomies. C, Fractional lengthening of the brachialis through the musculotendinous junction and subperiosteal release of the proximal brachioradialis from the distal humerus through the same incision. After spreading of the tenotomies, the overlapping region of the biceps tendon is secured with three sutures.


The wound is closed with absorbable suture. A long-arm cast is applied with the elbow in full extension. The cast is worn for 3 weeks, followed by range of motion and splint fabrication.


Elbow Contracture Release for Fixed Deformity


Indications.


Fixed elbow contractures require a more extensive release. In general, functional upper extremities with an elbow flexion contracture of more than 40 degrees should be addressed. In the nonfunctional upper extremity, a flexion contracture that results in difficulties in dressing or recurrent intertriginous infections should be treated. Release of a severe elbow flexion contracture often results in a satisfying improvement in function and hygiene. A 45-degree improvement in the flexion contracture of the extremity is usually obtained. Many patients are able to accomplish tasks that were difficult before surgery. In a wheelchair-bound patient, flexion deformities of more than 100 degrees make assistance during transfers difficult and manipulation of objects or technologic devices on a tabletop impossible. Elbow release improves the ability to work at a tabletop and assist in transfers. Ambulatory patients can expect an improvement in use of the arm in two-handed activities and in the workable reach space of the extremity.


Contraindications.


Patients with weak elbow flexion may have a functional loss of elbow flexion after full elbow release. The risks of loss of elbow flexion must be weighed against the benefits of improved position and hygiene of the extremity. Therapy, splinting, serial casting, and stretching should be maximized prior to surgical intervention.


Technique.


The patient is placed supine on the operating room table. The entire extremity is prepped and draped. A sterile circular tourniquet is applied (HemaClear, OHK Medical Devices, Grandville, MI) that exsanguinates during application. For a fixed contracture, an “S”-shaped or “Z”-plasty incision is made centered over the antecubital fossa ( Figure 32.11 ). Antecubital veins are mobilized or ligated. The lateral antebrachial cutaneous nerve, emerging from the interval between the biceps and brachialis lateral to the biceps tendon, is identified and retracted laterally. The lacertus fibrosus is identified and incised from the biceps tendon. The median nerve and brachial artery are visualized. The radial nerve is isolated between the brachioradialis and brachialis muscles.




FIGURE 32.11


Elbow static contracture release. A, Preoperatively, the patient has a severe static flexion contracture of his elbow; passive extension is lacking at more than 90 degrees even with the patient asleep. B, “Z”-plasty incision in the antecubital fossa. C, The lateral antebrachial cutaneous nerve is protected. D, The lacertus fibrosus is transected. E and F, The biceps tendon is “Z”-lengthened. G and H, Myotomy and subperiosteal dissection origin of the brachioradialis. Note that the radial nerve branches to the brachioradialis are preserved. I, The brachialis tendon is visualized deep to the biceps, and the neurovascular bundle is retracted medially. J, Fractional lengthening and myotomy of the brachialis. K, After complete release of the anterior capsule, the “Z”-lengthened biceps tendon is repaired with ethibond suture. L, Postoperative elbow extension.

(Courtesy of Shriners Hospital for Children, Philadelphia.)


The brachioradialis is treated by myotomy. The muscle is isolated from the ECRB and the radial nerve. The muscle is cut using electrocautery for complete release. The biceps tendon is traced from its muscular origin to the radial tuberosity. The tendon is lengthened by “Z”-plasty along its entire length. Deep to the biceps tendon, the brachialis muscle-tendon junction is identified. A fractional lengthening is performed by cutting the tendon, leaving the muscle alone. The amount of extension gained is assessed. Any additional tight fascia is released. The neurovascular bundle is often the rate-limiting factor. Therefore, additional capsular release would not achieve considerable gains in extension. Additional gains in elbow position can be made by serial casting following surgery.


The biceps tendon lengthening is repaired with a tendon weave or end-to-end repair using a nonabsorbable suture. The wound is closed with absorbable suture. A long-arm cast is applied with the elbow in full extension. The cast is worn for 4 weeks, followed by range-of-motion movements and splint fabrication.


Authors’ Preferred Method of Treatment


Treatment decisions are based on repeated examinations and frank conversations with the patient and family. Nonoperative measures should be exhausted prior to surgery. Dynamic elbow spasticity that is not responsive to therapy can be treated by surgery via a transverse incision across the antecubital fossa, as described above (see Figure 32.10 ). This procedure is often performed during concomitant procedures to address the wrist, fingers, and/or thumb. Fixed contractures are less responsive to therapy. Contractures that interfere with care or function require surgery. The details of a more extensive procedure are detailed above. An “S”-shaped or “Z”-plasty incision is necessary to allow ample skin for closure. The neurovascular structures must be identified and protected. Postoperative serial casting may be used to further improve elbow extension. Biceps lengthening may result in a “Popeye” deformity contour of the anterior arm.



Critical Points

Elbow Muscle Release and Lengthening for Dynamic Spasticity or Fixed Flexion Contracture


Indications




  • •

    Dynamic elbow spasticity that has not been responsive to therapy


  • •

    Fixed flexion contracture greater than 40 degrees that interferes with function or hygiene



Preoperative Evaluation




  • •

    Individualize patient goals.


  • •

    Perform repeated clinical examinations.


  • •

    Maximize nonoperative modalities and consider botulinum toxin to predict surgical outcomes.


  • •

    Dynamic electromyography may be helpful in identifying spastic muscles.



Pearls




  • •

    Apply a sterile circular tourniquet (HemaClear, OHK Medical Devices, Grandville, MI) that exsanguinates during application and allows complete access to the elbow.


  • •

    Always identify and protect the neurovascular structures early in the procedure because they may be displaced by the spastic muscles and/or contracture.



Technical Points




  • •

    Make a transverse antecubital incision for dynamic spasticity and an “S”-shaped or “Z”-plasty incision for a fixed deformity.


  • •

    Identify the lateral antebrachial cutaneous nerve.


  • •

    Mild biceps lengthening via fractional technique; more extensive lengthening requires “Z”-lengthening.


  • •

    Mobilize the neurovascular bundle from the anterior surface of the brachialis prior to brachialis fractional lengthening.


  • •

    Identify the radial nerve in the interval between the brachialis and brachioradialis.



Pitfalls




  • •

    Failure to identify the neurovascular structures can lead to iatrogenic injury.


  • •

    Inadequate hemostasis can lead to postoperative hematoma.


  • •

    Careless skin handling can lead to wound dehiscence.



Postoperative Care




  • •

    Cast application is preferred to allow for wound and tendon healing.


  • •

    Begin active and passive range-of-motion exercises following cast removal.




Forearm


The forearm is the “forgotten joint” with regard to movement and balance in a child with spasticity. The forearm is articulated at its proximal and distal ends (proximal and distal radioulnar joints). The movement is balanced by two muscles that supinate (biceps and supinator) and two muscles that pronate (pronator teres and pronator quadratus).


Types of Operative Procedures


The spastic forearm is classically positioned in hyperpronation. Several operative procedures have been described to decrease the spastic pronation force on the forearm. Brachialis and brachioradialis transfers have also been described. Release of the pronator teres can be performed at its origin by a flexor-pronator muscle slide or at its insertion by a pronator teres tenotomy or rerouting. Studies have reported that pronator rerouting results in an increase in active supination of between 46 and 78 degrees, compared with 54 degrees for pronator tenotomy. However, in these reports the arc of motion was unchanged after pronator rerouting. This suggests that pronator teres rerouting may only reposition the forearm versus function as an active supinator. This finding has changed our approach to the spastic forearm, and we less commonly perform pronator teres rerouting. The pronator quadratus should not be released during pronator teres release, because this may result in loss of pronation, which is critical for “tabletop” and many technology-based activities of daily living and communication.


A forearm positioned in pronation for a prolonged period will become contracted in this position, with structural changes to the proximal and distal radioulnar joints. Tendon transfers are contraindicated with a fixed contracture or radial head dislocation. Options include interosseous membrane release combined with tendon transfer, osteotomy of the radius and/or ulna, or the one-bone forearm procedure.


The surgeon must consider the entire operative plan for the extremity because other operative procedures to improve wrist extension can also improve supination. In the laboratory, FCU to ECRB transfer achieved 84 degrees of supination, brachioradialis rerouting achieved 33 degrees of supination, and pronator rerouting was unable to achieve supination past neutral. However, these numbers may be different in vivo and may depend on the amount of pronation spasticity and phasic activity of transferred muscles. For example, FCU to ECRB transfer for wrist extension clinically increased supination by an average of 22 degrees.


Flexor-Pronator Origin Muscle Slide


Indication.


The flexor-pronator origin muscle slide was initially designed to release the ischemic muscles after established forearm compartment syndrome. The procedure releases the pronator teres as well as the wrist and digital flexors. In addition to releasing the pronation contracture of the forearm, the flexor-pronator mass that originates from the medial epicondyle can contribute to elbow flexion contracture. The procedure can be extended in a proximal direction to release other contractures about the elbow as well.


Contraindication.


The flexor-pronator muscle slide is an “all-or-none,” technically demanding procedure requiring surgical experience. The procedure can cause excessive weakness of the finger flexors and overcorrection of pronation deformity.


Technique.


The patient is placed supine on the operating room table. The entire extremity is prepped and draped. A sterile circular tourniquet is applied (HemaClear, OHK Medical Devices, Grandville, MI) that exsanguinates during application. A long incision is made along the medial corridor from above the elbow to the ulnar styloid. The skin is incised, and hemostasis is obtained with electrocautery. Loupe magnification is used throughout the procedure.


The ulnar nerve is identified and traced through the cubital tunnel. Proximal dissection is performed so that any investing fascia around the ulnar nerve and the arcade of Struthers is released. The nerve is released to the point where it can be transposed in an anterior direction ( Figure 32.12 ).




FIGURE 32.12


Flexor origin slide. A, Severe wrist and finger flexion deformity. B, Ulnar border incision with transposition of the ulnar nerve and dissection of all pronator and flexor forearm and finger muscle origins from the periosteum and interosseous ligament. C, Full extrinsic wrist and finger extension can be achieved; intrinsics may be released separately. D, Closure over a drain and casting in full finger and wrist extension.

(Reproduced with permission of Children’s Orthopaedic Center, Los Angeles, and Shriners Hospital for Children, Philadelphia.)


The flexor-pronator mass is incised directly off the ulna down to the medial collateral ligament. The collateral ligament is carefully preserved. The muscle is sequentially released from the ulna all the way to the wrist.


Subsequently, the release continues in an ulnar to radial direction. The release courses superficial to the brachialis muscle, where the median nerve and brachial artery are identified. The bifurcation into the radial and ulnar arteries is protected.


Directly on the interosseous membrane, the anterior in­terosseous nerve and artery are protected. Dissection proceeds superficial to the nerve and artery until the radius is encountered. Any taut muscle that originates from the radius (FDS, FPL) is released from its proximal origin.


The release is continued until the wrist and fingers can be extended completely. Closure is straightforward, leaving the ulnar nerve in an anterior position. We often place a deep drain beneath the flexor-pronator mass. A long-arm cast is applied with the wrist and digits in extension. The forearm is positioned in midsupination.


The arm is immobilized in a cast for 4 weeks with the elbow extended to 45 degrees, the forearm supinated, and the wrist and digits in extension. A removable splint is continued for 4 additional weeks, allowing removal for range-of-motion movements and therapy. After 2 months, splinting is converted for night use; it is discontinued 1 month later unless there is a tendency for recurrence of the deformity.


Release of Pronator Insertion


Indication.


Pronator insertion release alleviates the deforming force of the pronator teres muscle. Release alone is indicated in patients who have excessive pronation but no voluntary control of pronation. In patients who do not have active supination, a tendon transfer may be necessary to augment supination even after release of the pronator.


Contraindication.


Isolated pronator release in patients who lack active supination will not improve the deformity. Fixed deformity requires additional interosseous membrane release, osteotomy of the radius and/or ulna, or a one-bone forearm procedure.


Technique.


Topographically, the pronator teres insertion is just proximal to the radial sensory nerve as it exits from beneath the brachioradialis muscle. A straight or curvilinear radial boarder incision allows direct access to the pronator insertion. Small branches of the lateral antebrachial cutaneous nerve are identified and protected. The radial sensory nerve is isolated between the brachioradialis and the ECRL. Proximal to the radial sensory nerve, the brachioradialis is elevated to expose the underlying radius. The tendon of the pronator is isolated inserting into the radius. A tenotomy of the entire tendon is performed under direct visualization.


After release, primary closure and an above-the-elbow cast or sugar tong splint is placed to keep the forearm in supination for 4 to 6 weeks. A removable supination splint is worn for an additional 4 weeks, with place-and-hold active and passive supination and active pronation exercises as part of the protocol.


Pronator Teres Rerouting


Indication.


Rerouting of the pronator converts this muscle to a supinator. Clinical results demonstrate a 50% increase in supination and correction of the reverse grasp position. It is indicated in patients who have active control of the pronator and lack active supination. The tendon can be released and rerouted through the interosseous space; alternatively, the pronator can be “Z”-lengthened and the distal portion brought around the radius and through the interosseous membrane from dorsal to volar, where it is woven into the proximal tendon.


Contraindication.


Pronator teres rerouting should be used sparingly in patients without active pronation control as the transfer will act only as a tether.


Technique.


The patient is placed supine on the operating room table. The entire extremity is prepped and draped. A sterile circular tourniquet is applied (HemaClear, OHK Medical Devices, Grandville, MI) that exsanguinates during application. A longitudinal incision is made over the radial aspect of the forearm. The superficial branches of the lateral antebrachial cutaneous nerves are mobilized. The radial sensory nerve is identified emanating from the brachioradialis muscle-tendon. The nerve is traced in a proximal direction and the brachioradialis muscle is elevated. Just proximal to this point, the pronator teres tendinous attachment to the radius is identified.


The pronator muscle is released and dissected in a proximal direction to facilitate rerouting. A spacious window is made in the interosseous membrane to accommodate the transfer. The pronator teres tendon is lengthened in a “Z” fashion. The distal part of the tendon is rerouted from dorsal to volar through the window in the interosseous membrane. The distal part is sutured back to the proximal part under slight tension. Alternatively, the pronator teres tendon is detached and transferred through the interosseous membrane and around the radius and reattached to its former insertion site with transosseous sutures or suture anchors with the forearm in supination.


Authors’ Preferred Method of Treatment


Mild pronation contracture of the forearm is treated by release or rerouting of the pronator teres insertion ( Figure 32.13 ). In patients with active supination, we prefer a pronator tenotomy. If the patient has active pronation but no active supination, rerouting of the pronator is performed. In patients who have a pronation contracture combined with wrist and finger flexion deformity, a flexor-pronator muscle slide is preferred. In patients with a moderate to severe pronation deformity, an osteotomy of the radius and/or ulna or a one-bone forearm procedure is preferred.



Critical Points

Pronator Teres Tenotomy or Rerouting


Indications




  • •

    Pronator tenotomy: active supination short of neutral


  • •

    Pronator rerouting: weak to no active supination with volitional pronator teres



Contraindications




  • •

    No active pronation control


  • •

    Fixed deformity



Preoperative Evaluation




  • •

    Test for active supination and pronation.



Pearl




  • •

    Identify the pronator teres insertion just proximal to the radial sensory nerve as it exits from beneath the brachioradialis muscle.



Technical Points




  • •

    Make a longitudinal incision on the radial aspect of the midforearm.


  • •

    Protect the medial antebrachial cutaneous nerve.


  • •

    Identify the superficial radial nerve.


  • •

    Develop the interval between the brachioradialis and the wrist extensors.


  • •

    For pronator release, simply divide the tendon completely.


  • •

    For pronator rerouting, elevate the insertion of the pronator with a periosteal sleeve.



    • •

      Expose the radius at the level of the insertion.


    • •

      Incise the interosseous membrane at this level over a 2-cm distance.


    • •

      Pass the pronator from volar to dorsal through the interosseous membrane with a right-angled clamp.


    • •

      Suture the pronator to a drill hole in the radial aspect of the radius or use suture anchors in the radius.




Pitfall




  • •

    Pronator release or rerouting will not be efficacious in patients with substantial contracture of the forearm. Additional interosseous membrane release, osteotomy of the radius and/or ulna, or a one-bone forearm procedure is necessary.



Postoperative Care




  • •

    Use a sugar tong splint or long-arm cast for 1 month with the wrist and forearm in neutral position or midsupination.


  • •

    Remove immobilization at 1 month and fabricate a splint that positions the forearm in neutral position or midsupination.


  • •

    During the second month, the splint is removed only for therapy.


  • •

    Discontinue the splint at 2 months after surgery.





FIGURE 32.13


Pronator rerouting. Through a longitudinal incision in the middle aspect of the forearm (A) , the pronator is taken down from its insertion on the radius and routed through the interosseous septum (from volar to dorsal) (B and C) and reattached to a drill hole in the dorsal radial radius (D and E) . F, Closed incision with passively improved supination.

(Reproduced with permission of Children’s Orthopaedic Center, Los Angeles.)


Wrist and Digital Extension


Types of Operations


Balance of the wrist and digits is important to improve hand function in children with spasticity. Decision making to match the best procedure with an individualized patient predominantly relies on the degree of wrist and finger joint contractures as well as tone and muscle spasticity of the wrist and digital flexors. If assessment is difficult, median and/or ulnar nerve blocks can temporarily eliminate the flexor spasticity and allow a better evaluation. Ulnar deviation of the wrist may compound a flexion deformity and may be caused by a spastic or contracted FCU and/or ECU. The muscle causing the deformity can be cut, lengthened, or used as a transfer to augment its antagonist.


An integral part of the examination is the evaluation of digital function during wrist motion ( Figure 32.14 ). If the patient cannot actively extend the wrist to neutral, the wrist should be held in neutral by the examiner while the patient attempts active digital extension. Grasp and release must be evaluated to ensure that improvements in wrist extension will not decrease digital extension and affect object acquisition (see ). Similarly, the patient may rely on ulnar deviation of the wrist to increase thumb abduction for acquiring objects for pinch. If wrist ulnar deviation is lessened, a concurrent procedure to augment thumb abduction may be necessary.




FIGURE 32.14


A patient with good active digital extension but absent wrist extension.

(Copyright Michelle Gerwin Carlson.)


A patient who would benefit from greater wrist extension may be helped by several available operative techniques that would accomplish this and improve function. Potential donors include the ECU, FCU, pronator teres, and brachioradialis. Donor tendons are usually transferred to the ECRB due to its central location on the third metacarpal. When transferring the FCU, an alternative route through the interosseous membrane has been described to decrease the ulnar-deviating force on the wrist, but this also decreases the supination effect of the transfer. The choice of donor is based on a careful physical examination and surgical experience.


In patients with severe fixed wrist capsular contractures, a proximal row carpectomy may be an adjunct to allow extension of the wrist to neutral before tendon transfers can be performed. However, this combination is uncommonly performed because proximal row carpectomy yields a small gain in passive wrist extension. Wrist arthrodesis can be used to improve hygiene or function, however ; fusion may downgrade function due to loss of the tenodesis effect on the digital tendons. In a child, an epiphyseal arthrodesis or chondrodesis (wrist fusion that preserves the physeal plate) can be performed to allow continued growth if the patient has adequate ossification of the epiphysis and carpal bones. However, fusion is difficult to achieve secondary to the abundant pediatric cartilage.


Weak digital extension is less common than weak wrist extension and is associated with more severe disability. Transfer of the FCU to the extensor digitorum communis (EDC) has been recommended to improve digital extension while also improving wrist extension. Tendon transfers always perform best when “asked” to perform a single task, and the surgeon must be careful about “asking” too much from an already compromised muscle-tendon unit. Tendon transfers for digital extension are useful in patients who are unable to actively extend their fingers when the wrist is in extension. Zancolli and Zancolli defined three types of finger extension deformities and suggested a treatment algorithm ( Table 32.4 ). Patients with poor wrist and digital extension may benefit from a combination of tendon transfers, such as FCU to EDC and either ECU or pronator teres to ECRB.



TABLE 32.4

Finger Extension Deformities and Their Treatment




















Type Deformity Treatment
I Active digital extension possible with wrist extended less than 20 degrees from neutral No treatment or minimal fractional lengthening of digital and/or wrist flexors
II Active digital extension possible with wrist flexed more than 20 degrees from neutral Fractional lengthening of digital flexors in addition to augmentation of wrist extension and/or flexor carpi ulnaris tenotomy
III No active digital extension Augmentation of digital extension with flexor carpi ulnaris transfer to extensor digitorum communis

Zancolli EA, Zancolli ER, Jr: Surgical management of the hemiplegic spastic hand in cerebral palsy. Surg Clin North Am 61:395–406, 1981.


Results of wrist extension transfers have demonstrated improved function in approximately 80% of patients. FCU to ECRB transfer has shown good results, with an average improvement in resting wrist posture from 41 degrees of flexion to 11 degrees and an improvement in the arc of motion, with increased wrist extension and a compensatory loss of flexion. The total range of motion is unchanged after this procedure, although wrist extension has been shown to improve by 35 to 45 degrees. The greatest improvement in function of the hand is seen in patients without flexion contractures who use a wrist flexion to augment digital opening when attempting digital extension. Children with dystonia, neglect, poor stereognosis, and little voluntary limb control will demonstrate inferior outcomes after all wrist extension tendon transfers.


Flexor Carpi Ulnaris to Extensor Carpi Radialis Brevis Transfer (Green’s Transfer)


Indication.


FCU to ECRB transfer is indicated in patients who have a dynamic wrist flexion deformity, flexible wrist joint, intact although possibly weak finger extensors, and absent or weak wrist extension.


Contraindication.


A nonfunctioning FCR is a relative contraindication because the result will be loss of active wrist flexion and a wrist extension deformity. Preoperative FCU evaluation by electromyography can be helpful because children with dystonia and irregular phasic contractions will have unreliable results. If the finger extensors are absent, the FCU may be more appropriately transferred to the EDC. If the wrist joint is inflexible and the digital flexors are tight, additional concurrent procedures need to be performed to provide reliable outcomes after FCU to ECRB transfer.


Technique.


The FCU can be harvested through multiple small incisions or a single long ulnar border incision ( Figure 32.15 ). If smaller transverse or longitudinal incisions are used, the first incision is made over the FCU insertion on the pisiform at the wrist flexion crease. Tension on the tendon allows the proximal aspect of the tendon to be palpated. The more proximal incisions are made at proximal palpable points on the tendon in the forearm. Transverse incisions are more aesthetic, but care must be taken to protect the ulnar neurovascular bundle during harvest. In addition, the large muscular and sheath attachments of the FCU along the ulna may make passing the tendon beneath the skin difficult. Following FCU identification within each transverse incision, the FCU is transected at its insertion on the pisiform and progressively mobilized through the proximal incisions. The transverse incisions are recommended for surgeons who have considerable experience. Alternately, the incisions can be made longitudinally. To ensure adequate length and estimate insertion location, the tendon is passed around the ulnar aspect of the forearm, over the skin, to the point where it intersects with the ECRB. The goal is to insert the tendon at the wrist rather than within the forearm. This maneuver also ensures ample tendon to allow a Pulvertaft weave. A transverse or longitudinal incision is made over the ECRB at the intended weave site. A subcutaneous tunnel is created from the dorsal incision to the volar ulnar wound. The tunnel should be deep to the subcutaneous tissue and sensory nerves but superficial to all tendons. Care should be taken to ensure that this tunnel is as direct as possible. Any fibrous septa between the FCU and ECU are opened widely to prevent kinking of the muscle as it passes along the ulnar border.




FIGURE 32.15


Flexor carpi ulnaris to extensor carpi radialis brevis transfer. A and B, The flexor carpi ulnaris tendon is harvested through two volar incisions, one distal at the pisiform and the other over the midforearm. The flexor carpi ulnaris can be harvested using a tendon stripper inserted distally. C, The tendon is wrapped over the forearm to mark the site of attachment to the extensor carpi radialis brevis tendon. D and E, An incision can then be made at this spot and the tendon tunneled subcutaneously. F, The length gained from the subcutaneous tunnel allows easy weaving in a Pulvertaft fashion.

(Courtesy of Shriners Hospital, Philadelphia.)


The FCU is passed through this tunnel toward the ECRB insertion. A Pulvertaft weave is performed between the two tendons, with each weave secured with nonabsorbable sutures. The weave should be done with maximal tension on the tendon ends while the wrist is held in neutral to slight extension. Usually, only one or two weaves can be performed. Following the initial weave, tension should be assessed by allowing the wrist to sit in its resting position. Neutral to slight extension is preferred; too loose or too tight is bad. Care should be taken to ensure that the weave does not encroach on the intersection with the EPL or the extensor retinaculum. If this does occur, the EPL can be transposed and/or a portion of the retinaculum divided.


The wrist is immobilized in 30 degrees of extension for 3 to 4 weeks. A splint is worn for 4 to 6 weeks and removed for hygiene, activities, and range-of-motion exercises. Standard tendon transfer training is performed by a hand therapist. Electrical stimulation and biofeedback training can be helpful in patients having difficulty firing the transfer. Nighttime splinting is continued for an additional 3 to 4 weeks and then discontinued.



Critical Points

Flexor Carpi Ulnaris to Extensor Carpi Radialis Brevis Transfer


Indications




  • •

    Inability to actively extend the wrist to neutral with a functioning FCU and FCR


  • •

    Adequate finger extension with the wrist positioned in extension



Contraindications




  • •

    No active control of the FCR


  • •

    Dystonia



Pearl




  • •

    After tendon transfer, the wrist should passively rest in neutral to slight extension.



Pitfalls




  • •

    If weak digital extension is not addressed concurrently, wrist extensor transfer will worsen digital extension and object acquisition.


  • •

    Overtightening of the transfer will result in a fixed wrist extension posture and impair digital extension.



Technical Points




  • •

    Begin to harvest the FCU at the pisiform because length is always an issue.


  • •

    Mobilize the FCU muscle-tendon up to the midforearm.


  • •

    Drape the FCU over the skin from the volar wound to the dorsal forearm to assess the location of the tendon weave.


  • •

    Create a Pulvertaft weave of the FCU into the ECRB with maximal tension on the tendon and the wrist in neutral to slight extension.



Postoperative Care




  • •

    The wrist is splinted in 30 degrees of extension.


  • •

    One month after surgery, fabricate a removable wrist extension splint and begin therapy.


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