Orthopaedic Knowledge Home Study by R. Alexander

Spinal Cord Injury Orthopaedic Knowledge Update 8 patients ambulate independently upon discharge from When the trauma patient is initially assessed at the rehabilitation; patients are more likely to ambulate scene of injury, if there is any suspicion of SCI, addi- when the upper limb is weaker than the lower limb on tional attention is given to maintaining maximal oxygen- the affected side. ation and normalization of blood pressure. These crucial early interventions help to protect the fragile spinal Anterior Cord Syndrome cord blood perfusion. Generally these interventions in- clude nasal cannula administration of oxygen and vaso- Anterior cord syndrome is associated with lesions that pressors to maintain an optimal blood pressure. Crystal- affect the anterior two thirds of the spinal cord but pre- loids are initially administered; however, if adequate serve the dorsal columns. Although anterior cord syn- pressures cannot be maintained in the SCI patient, pres- drome can be associated with direct injury to the ante- sors (dopamine) should be quickly added to resuscita- rior cord, it is most commonly caused by lesions of the tion efforts. Blood pressure should be maintained at a anterior spinal artery, which supplies the anterior two systolic pressure between 80 and 100 mm Hg to mini- thirds of the spinal cord and can be injured through mize the proliferation of secondary insults to the spinal thrombosis or embolism. There is inconsistent and vari- cord from hypoxemia. able loss of motor strength and pinprick sensation with preservation of light touch, deep pressure, and proprio- The importance of maintaining adequate spinal cord ception. Prognosis is poor with less than a 20% chance perfusion following injury is widely accepted though of motor recovery. largely unproven. There exists a hypothetical watershed region of partial injury within the cord tissue that has Conus Medullaris and Cauda Equina Syndromes the potential for functional recovery if perfusion is maintained and further trauma avoided. Healthy cord The conus medullaris is the terminal segment of the spi- tissue demonstrates autoregulation of blood flow capa- nal cord. The segment above it is termed the epiconus ble of maintaining perfusion through a wide range of and it consists of spinal cord segments L4 to S1. Lesions systemic blood pressure. This autoregulatory function of the epiconus cause upper motor neuron dysfunction can be lost following injury, leaving the watershed re- of the lower lumbar and sacral segments. Recovery is gion vulnerable to fluctuations in systemic blood pres- similar to that of other upper motor neuron SCIs. Le- sure. Maintenance of mean arterial pressure above sions of the conus medullaris affect the S2-S5 segments 85 mm Hg has been recommended for at least 7 days and there is a combination of upper and lower motor following injury. Initial efforts at volume expansion us- neuron deficits because the cauda equina is often in- ing crystalloid or colloid may be insufficient, and re- jured simultaneously. Frequently the lower motor neu- quire subsequent administration of dopamine or neo- ron deficits predominate. With conus medullaris injuries, synephrine. recovery is limited. Mortality in the acute phase of SCI is frequently sec- Lesions below the L1 vertebral level injure the ondary to pulmonary failure and shock. Shock is ini- cauda equina, producing motor weakness and atrophy tially managed by the Advanced Trauma Life Support of the lower extremities with bowel and bladder in- protocol of crystalloid resuscitation, until it is clear that volvement and areflexia. Cauda equina injuries have a supplementary pressors are required to maintain ade- better prognosis for recovery than other SCIs, because quate blood pressure. Early and aggressive pulmonary the roots are histologically peripheral nerves and regen- support is essential in the acute stages after injury. Pneu- eration can occur. Often, traumatic SCI will cause a monia and atelectasis are difficult to avoid and repre- combination of conus and cauda equina injuries. sent the most common early complications. The fre- quency and severity of these occurrences is related to Acute Management of Spinal Cord Injury the level of the SCI, as it relates to the remaining inner- vation of the respiratory muscles. In the patient with Acute intervention after SCI may be surgical or nonsur- acute SCI, respiratory support is often required. gical. Nonsurgical intervention consists of pharmaco- logic and realignment techniques. The role of surgical The loss of sympathetic tone, found with lesions intervention for acute SCIs is still widely debated; how- above the T6 level, leads to unopposed vagal input. This ever, there exists a significant body of information iden- imbalanced neural activity can cause increased bron- tifying the benefit of urgent surgical intervention in ani- chial secretions and ultimately lead to mucus plug for- mal SCI models. Human clinical trials and retrospective mation. Mucus plugs, an impaired cough reflex, and analysis have been unable to show a statistical improve- compromised respiratory muscles all can cause early ment in neurologic outcome related to surgical interven- respiratory arrest in the patient with acute SCI. tion. According to one recent study, subacute and late decompressive procedures have a major role in the High-dose steroids are administered in the patient treatment of incomplete SCI. with acute SCI. Intravenous administration of the gluco- corticoid methylprednisolone in high doses (loading dose 30 mg/kg bolus over 15 minutes followed by 622 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 51 Spinal Cord Injury 5.4 mg/kg hr) is recommended, with the length of time ting. These injuries pose the risk of significant neuro- of administration dependent on the time of presenta- logic deterioration if undiagnosed or untreated. tion. If administration of the steroid is initiated within 3 hours of the SCI, administration for 23 hours is recom- Indirect reduction is infrequently performed in the mended, whereas if steroid administration is initiated acute setting for the treatment of a thoracolumbar or between 3 to 8 hours after SCI, the steroid should be lumbar injury in the presence of a spinal cord, conus, or continued for 48 hours. The original clinical trials did cauda equina injury. Some physicians advocate early not recommend the use of methylprednisolone if the pa- open reduction and stabilization of thoracolumbar tient presents after 12 hours from the time of injury. Ad- fracture-dislocations with accompanying neural deficits. ditionally, the study cohort did not include cord injuries Keeping in mind that most SCI models show irrevers- caused by ballistic/penetrating trauma or those with ible cord pathophysiology within 6 to 8 hours, advocates nerve root injury. The studies supporting this protocol of early decompression, realignment, and stabilization have come under increasing scrutiny over the past few stress the importance of acute intervention. Such inter- years. vention, however, often is not possible because of ground transportation of patients and hospital referral Shortcomings of the Second National Acute Spinal networks. Cord Injury Study (NASCIS II) include lack of data re- garding the functional significance of apparently incre- Medical Complications of Spinal Cord Injury mental improvements in neurologic scores, failure to present raw study data, and absence of a clearly defined Cardiac initial study hypothesis. Follow-up post hoc subgroup analysis suggests that placebo administration greater The most important postinjury treatment issue is cardio- than 8 hours following injury achieved an equivalent im- vascular sequelae. These are often subdivided into direct provement in motor score in patients who had methyl- complications resulting from the injury itself (for exam- prednisolone administered within 8 hours of injury. ple, hypotension, bradycardia, and autonomic dysre- NASCIS II has also been criticized for lacking func- flexia) after spinal shock has resolved and indirect com- tional outcome measures. Currently the use of high-dose plications resulting from sequelae of immobilization and steroids in the treatment of SCI is an off-label use of the relatively sedentary lifestyle postinjury (for exam- this drug and has not been approved for this indication ple, deep venous thrombosis [DVT], pulmonary embo- by the Food and Drug Administration. High-dose ste- lism, and coronary artery disease). roid treatment also has been associated with an in- creased incidence of gastrointestinal bleeding as well as Autonomic dysreflexia is characterized by a sudden an increased rate of infection. sympathetic discharge causing an exaggerated increase in blood pressure, often with bradycardia, in response to The glucocorticoids are stabilizing agents that have a noxious stimulus originating below the injury. This been shown to affect the neural membranes, preventing syndrome usually occurs in 48% to 85% of patients with uncontrolled intracellular calcium influx. Additional SCI above the T6 level. Associated symptoms include stated positive effects include decreasing the lysosomal headache, mydriasis, piloerection, nasal congestion, enzyme effects and reducing secondary swelling and in- flushing, and sweating. The patient can also experience flammation. no symptoms at all, with silent blood pressure elevation. The most common cause of autonomic dysreflexia is A second nonsurgical intervention is early indirect bladder distention, followed by fecal impaction, pressure reduction of the spinal canal via cranial tong traction. ulcers, ingrown toenails, fractures, and abdominal emer- The increasing availability of MRI has dampened some gencies. Treatment includes putting the patient in a sit- of the enthusiasm for rapid closed reduction techniques, ting position, removal of precipitating stimuli, and if the as MRI has identified the presence of associated herni- cause cannot be found, use of antihypertensive agents ated intervertebral disks. Closed reduction of the trau- (such as nifedipine, nitrates, and angiotensin-converting matic deformity is directed toward restoration of the enzyme inhibitors). spinal column to its premorbid alignment and re- establishment of the diameter of the bony spinal canal. Deep Venous Thrombosis This reduction maneuver is applicable to cervical spine injuries only. Additionally, before any significant amount DVT has been reported in 15% to 80% of SCI patients of traction (> 10 lb) can be applied through the tongs, and usually develops during the first 2 weeks after in- special effort must be made to rule out the possibility of jury. Residual motor function in the lower extremities an associated occult craniocervical injury. For patients and the level of SCI contribute to the overall incidence. with distractive injuries of the cervical spine, craniocer- The estimated incidence of pulmonary embolism is 2% vical dissociations, or fracture-dislocations associated to 16%. All patients should receive prophylaxis for with ankylosing spondylitis, application of a holding de- DVT unless otherwise contraindicated. If prophylaxis is vice such as a halo is recommended in the urgent set- delayed more than 72 hours, tests to exclude the pres- ence of clots should be done. Anticoagulant prophylaxis American Academy of Orthopaedic Surgeons 623

Spinal Cord Injury Orthopaedic Knowledge Update 8 with either low-molecular-weight heparin or adjusted Individuals with SCI are at a high risk for urinary dose unfractionated heparin should be initiated, unless tract infection; complications caused by such infections contraindicated, within 72 hours of injury. Vena cava fil- are the most common cause of SCI morbidity. Other ter placement is recommended in SCI patients for complications include bladder and renal calculi, renal whom anticoagulant prophylaxis has failed or who have failure, and bladder carcinoma. Individuals with SCI anticoagulation contraindications. Filters should also be should have annual urologic evaluations including func- considered for SCI patients with high-level tetraplegia, tional studies. or for those with thrombosis of the inferior vena cava despite the use of anticoagulants. Anticoagulant prophy- Bowel laxis should continue for patients who are categorized as motor incomplete on the ASIA impairment scale Similar to the neurogenic bladder, the neurogenic bowel while they are hospitalized and for 8 to 12 weeks in mo- may be either spastic or flaccid. Patients are placed on a tor complete patients, depending on risk factors. Pa- bowel program with predictable, regular, timely, and tients with chronic SCI remain at increased risk for thorough evacuation of the bowels without the occur- DVT, and reinstitution of prophylactic measures should rence of incontinence or complications. Pharmacologic be considered for patients with chronic SCI who are im- agents are not always needed for long-term use but can mobilized and on bed rest for a prolonged period, or for be an effective adjunctive tool to facilitate the bowel those who are to undergo surgical procedures. program. A common starting routine for patients with a neurogenic bowel includes a stool softener three times Pulmonary daily, a laxative at bedtime, and a suppository in the morning after breakfast. A bowel routine after eating Pulmonary complications after SCI remain the leading makes use of the gastrocolic reflex. If a patient usually cause of death in patients with tetraplegia and paraple- has a bowel movement in the evening, then the laxative gia. Pneumonia accounts for 18.9% of deaths in the first can be given at noon and an enema or suppository in year after injury. The problems of pulmonary manage- the evening after dinner. It is difficult for patients with a ment can be classified into three main categories: secre- true lower motor neuron bowel to achieve continence tion management, atelectasis (and its sequelae), and hy- and a bulk laxative may be needed to limit loose stool poventilation. At least two of the following treatments formation with diarrhea. should be available to patients: deep pulmonary suction- ing, chest physiotherapy, assisted cough methods (for Skin example, quad cough), mechanical insufflation- exsufflation, abdominal binders, frequent position Pressure ulcers are a daily concern for patients with changes, incentive spirometry or resistive devices, and SCI. It is estimated that up to 80% of individuals with positive pressure ventilation. SCI will have a pressure sore during their lifetime, and 30% will have more than one pressure sore. Education Bladder in pressure ulcer etiology (including pressure and shear), use of appropriate equipment to help decrease The bladder is usually affected in one of two ways after ulcers, and weight shifts, while seated and in bed is nec- injury. A spastic bladder, or upper motor neuron blad- essary. The treatment of pressure sores may include der, fills with urine and a reflex automatically triggers dressings, bed rest, and surgery. All factors that contrib- the bladder to empty. A flaccid bladder, or lower motor uted to pressure ulcer development must be eliminated neuron bladder, results when the reflexes of the bladder or minimized. Treatment can be very costly in terms of muscles are slowed or absent. A flaccid bladder can be- lost wages and additional medical expenses. come overdistended or stretched. Although the upper tracts are at risk in both conditions, they are at greater Neuromusculoskeletal risk in a spastic bladder. Bladder sphincter dyssynergia occurs when the sphincter muscles do not relax when After SCI, many changes occur in bone metabolism. An the bladder contracts, which may also place the upper imbalance between bone formation and bone resorption tracts at risk for injury. This may occur with upper mo- rapidly develops, resulting in bone loss and osteoporosis. tor neuron dysfunction. To treat the neurogenic bladder, Within the first 4 to 6 months, 25% or more of bone SCI patients are placed on a bladder management pro- mass is lost. By 16 months, bone mass homeostasis is gram, which will allow acceptable bladder emptying reached with bone mass at 50% to 70% of normal and with convenience and help to avoid bladder accidents near the fracture threshold. Fractures are very common and infection, and long-term upper tract damage sec- in patients with SCI. Data from the Model SCI Systems ondary to reflux. Common treatment options include show that 14% of patients with SCI will have had a frac- clean intermittent catheterization, an indwelling cathe- ture within 5 years after injury. This percentage in- ter, and for men, an external condom catheter. creases to 28% after 10 years, and 39% after 15 years. The frequency of fractures increases with age and com- 624 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 51 Spinal Cord Injury pleteness of injury, and is higher in women than men. there is an improved prognosis of recovering antigravity Most fractures are in the lower extremities and result strength the faster the recovery begins. According to the from falls; fractures can also occur with routine activi- literature, muscles with grade 1 and 2 strength at ties of daily living and range-of-motion exercises. Treat- 30 days have a 97% chance of recovery to 3/5 strength ment of fractures in nonambulatory patients with SCI is at 1 year. In comparison, in the first muscle below the somewhat controversial. Circumferential plaster casts or neurologic level of injury with 0/5 strength at 1 month, traction can cause skin breakdown, and surgical inter- only 57% recover to at least 1/5 strength, and only 27% vention for femoral shaft and distal femur fractures is recover to 3/5 or more strength at 1 year. Most upper associated with a high complication rate because of extremity recovery occurs during the first 6 months, bone quality, risk of osteomyelitis, and recurrent bacter- with the greatest rate of change during the first 3 emia. Surgical intervention may be indicated when non- months. surgical management fails to control rotational defor- mity, if vascular supply is jeopardized, or in proximal Upper extremity recovery in patients with incom- femur fractures with severe spasticity. Often fractures plete tetraplegia is approximately twice as great as for are treated with soft splints without bed rest, and a those with complete tetraplegia. For patients who are wheelchair is used to provide functional positioning for initially sensory incomplete, the prognosis for motor re- healing. covery is much more favorable in those with pinprick sparing than in those in whom light touch sensation Heterotopic ossification is the formation of true alone is spared. bone at ectopic sites and occurs in up to 50% of adults with SCI. Ankylosis occurs in approximately 5% of pa- For patients with complete paraplegia, 76% do not tients. Most commonly, heterotopic ossification develops show a change in neurologic level of injury from 1 between 1 to 4 months after injury and 90% develops month to 1 year after injury. Even without a change in around the hip, followed by the knee and elbow. De- neurologic level, patients with incomplete paraplegia scription of the diagnosis and treatment of this condi- have the best prognosis for lower extremity and func- tion can be found in chapter 53. tional recovery. Overall, 80% of patients with incom- plete paraplegia regain strength to grade 3 or more in Spasticity is a common sequelae of upper motor hip flexors and knee extensors at 1 year. The absence of neuron SCI. It may enhance function and maintain mus- any motor function at 1 month after injury is not an ab- cle bulk, but when poorly controlled, spasticity may lead solute indicator of poor motor recovery. to impaired function, pain, and decreased quality of life. A full discussion of spasticity is found in chapter 52. Most of the recovery after SCI is spontaneous, but it may be enhanced by several factors. Active exercise can Prognosis After Spinal Cord Injury promote motor recovery whereas immobilization may impede motor recovery. Using body weight-supported Recovery of motor function has been documented for at and interactive locomotor training, ambulation recovery least 2 years after injury and changes in neurologic sta- may be enhanced in patients with incomplete SCI. Sero- tus may continue after 2 years. Recovery from SCI de- tonergic and neuroadrenergic drugs may enhance loco- pends on the initial strength of the muscles, and most motor recovery, whereas drugs with gamma- importantly, on whether the injury is complete or in- aminobutyric acid may impede ambulation. complete. Vertebral displacement less than 30% and age younger than 30 years at the time of injury are factors Functional Outcomes associated with improved recovery. No correlation has been found between degree of vertebral wedging, type C1 through C4 Tetraplegia of fracture, or etiology of injuries. In evaluating changes after SCI, MRI is the best modality to show intramedul- Patients with C1 and C2 lesions may have functional lary detail such as hematoma and edema. A hemorrhage phrenic nerves. In these patients, implanted phrenic found with acute MRI correlates with the poorest prog- nerve pacemakers can be used, and pacing of the dia- nosis, followed by contusion and edema. A normal MRI phragms may be simultaneous or alternating. If secre- scan correlates with the best prognosis. Although MRI tions are not a problem, tracheostomies may be plugged may augment the physical examination, it alone is not as or discontinued. accurate a predictor of SCI recovery as the physical ex- amination. Patients with C3 lesions have impaired breathing and are often ventilator-dependent. They can shrug their Ninety percent of patients with complete tetraplegia shoulders and have neck motion, which may permit the will recover one root level of function. The initial operation of specially adapted power wheelchairs and strength of the muscle is a significant predictor of equipment (such as tape recorders, computers, tele- achieving antigravity strength and the rate of strength phones, page turners, automatic door openers, and other recovery. In patients with no initial motor strength, environmental control units). Adaptive devices include mouth (sip and puff) and voice activation controls, or chin, head, eyebrow, or eye blink controls. Patients with American Academy of Orthopaedic Surgeons 625

Spinal Cord Injury Orthopaedic Knowledge Update 8 C4 lesions may not require respiratory equipment be- C7 to C8 Tetraplegia yond the initial acute care stage, but may have the same functional equipment needs as ventilator-dependent pa- Patients with C7 tetraplegia have functional triceps, can tients. bend and straighten their elbows, and also may have en- hanced finger extension and wrist flexion. As a result, In addition to powered wheelchairs, patients with these patients have enhanced grasp strength, which per- C1-C4 tetraplegia require assistance with all personal mits enhanced transfer, mobility, and activity skills. They care, turning, and transfer functions. Headrests, troughs can turn and perform most transfers independently; can or a lapboard (for the upper extremities), and lifts may propel a manual wheelchair on rough terrain and slopes, be necessary. Bed surfaces with two or more segments and may therefore not need a powered wheelchair; can that are alternately inflated and deflated may be indi- drive a specialized van; and can perform most daily ac- cated for patients who do not have assistance for turn- tivities such as cooking and light housework, and there- ing. Power recliners allow independent seated weight fore may occasionally live independently. They may, shifts. Patients with partial C5 function may benefit however, require assistance for bowel care and bathing. from adaptive equipment to enable feeding, writing, and C8 tetraplegia patients have flexor digitorum profundus typing. function, which permits all arm movement, with some hand weakness. They can propel a manual wheelchair C5 Tetraplegia for community distances, including in and out of a car and over curbs, and may even become wheelchair inde- Patients with C5 tetraplegia have functional deltoid pendent. and/or bicep musculature. They can internally rotate and abduct the shoulder, which causes forearm pronation by Ambulation After Spinal Cord Injury gravity. They can externally rotate the shoulder and cause supination and wrist extension and can flex the el- Up to 90% of SCI patients who are initially sensory in- bow. C5 tetraplegia patients require assistance to per- complete and motor complete, with preserved pinprick form bathing and lower body dressing functions, for sensation, will have sufficient motor recovery to walk at bowel and bladder care, and for transfers. With the use the time of discharge from rehabilitation. Motor incom- of adaptive equipment, C5 tetraplegia patients can feed plete patients have a better prognosis for ambulation themselves, perform oral facial hygienic and upper body than sensory incomplete patients. Patients who are able dressing activities, operate some equipment (such as to walk in the community have at least fair hip flexor computers, tape recorders, telephones), and participate strength bilaterally and fair strength in at least one knee in leisure activities. They can propel manual wheelchairs extensor, so that the maximum bracing needed is one short distances on level surfaces. Powered wheelchairs long leg and one short leg orthosis. The Waters Ambula- are needed for community distances and outdoor ter- tory Motor Index as well as the ASIA Lower Extremity rain. Motor Score have been found to correlate and the de- terminants between motor power and walking ability C6 Tetraplegia still were applicable. The Lower Extremity Motor Score is determined by adding of the muscle grades of the 10 Patients with C6 tetraplegia have musculature that per- key muscles. All patients with incomplete injuries who mits most shoulder motion, elbow bending, and active have a lower extremity motor score of greater than or wrist extension. Tenodesis orthoses support tenodesis equal to 20 at 1 month will progress to ambulation by 1 training early in recovery. Wrist-driven flexor hinge year postinjury (Table 3). splints permit pinching strength that is needed for cath- eterization and work skills. Short opponens orthoses Tendon Transfer Surgery with utensil slots, writing splints, Velcro handles, and cuffs permit feeding, writing, and oral facial hygiene. C6 The basic principle of upper extremity muscle transfers tetraplegia patients can perform upper body dressing is to use functioning proximal musculature to control without assistance; may seldom perform lower body distal parts, with minimal risk of loss of function. Arthro- dressing without assistance; may seldom catheterize desis may be performed in conjunction with tendon themselves and perform their bowel program with assis- transfers to stabilize a joint. Wrist fusion is generally tive devices; can perform some transfers independently contraindicated in patients with tetraplegia because loss with a transfer board; can turn independently with the of wrist extension interferes with manual wheelchair use of side rails; and can relieve pressure by leaning for- propulsion and transfers. Upper extremity surgery is ward, alternating sides, or possibly by push-ups. Water usually not performed before the patient has completed mattresses can lower pressure sufficiently to eliminate the rehabilitation program. the need for turning during the night. They can propel a manual wheelchair short distances on level terrain, oper- At the C5 level, patients have functional use of the ate power wheelchairs, and may drive a specialized van. deltoids and elbow flexors. At this level, the most help- ful procedures are transfer of the brachioradialis to the 626 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 51 Spinal Cord Injury Table 3 | Lower Extremity Motor Score and Ambulation review of current and future directions in rehabilitation management. Spine 2001;26(suppl 24):S137-S145. Incomplete Tetraplegia This article reviews the medical literature to provide a Lower Extremity Motor Score at Percentage Ambulatory at framework for predicting neurorecovery and functional out- comes after SCI based on injury severity. The authors con- 1 Month 1 Year clude that within 72 hours to 1 month after SCI, it is possible to predict with reasonable accuracy the magnitude of expected 1-9 21 recovery based on physical examination (and use of the ASIA scale). Future directions for improving functional outcomes 10-19 63 through the use of novel interventions such as pharmaceutical treatment, functional neuromuscular stimulation, standard > 20 100 protocols to limit secondary injury, and functional training methods (such as body weight support) to maximize activity- Complete Paraplegia dependent neuroplasticity are also addressed. 1-9 45 Fehlings MG, Sekhon LH, Tator C: The role and timing of decompression in acute spinal cord injury: What do Incomplete Paraplegia we know? What should we do? Spine 2001;26(suppl 24): S101-S110. 0 33 This article reviews the role of surgical reduction and de- 1-9 70 compression, particularly early surgery. A review of the cur- rent evidence available in the literature suggests that there is 10-19 100 no standard of care regarding the role and timing of surgical decompression. The authors conclude that there are insuffi- extensor carpi radialis brevis to restore wrist extension cient data to support overall treatment standards or guidelines (C6 level) and transfer of the deltoid to the triceps to for this topic. The existence of biologic evidence from experi- provide elbow extension (C7 level). mental studies in animals is noted, which shows that early de- compression may improve neurologic recovery after SCI; how- Upper extremity reconstructive surgery, or func- ever, it is concluded that the relevant time frame in humans tional neuromuscular stimulation of the upper extrem- remains unclear. ity, or both surgery and stimulation can improve func- tion at the C6 level. Stimulation can be provided by Hurlbert RJ: The role of steroids in acute spinal cord in- external, percutaneous, or implanted electrodes, by jury: An evidence-based analysis. Spine 2001;26(suppl shoulder motion using an external system, by key and 24):S39-S46. palmar grip and release, or by a bionic glove, an electri- cal stimulator garment that provides controlled grasp This is a literature review of methylprednisolone protocol and hand opening. that attempts to evaluate the role of steroids in nonpenetrat- ing (blunt) SCIs. From an evidence-based approach, the au- To restore lateral or key grip in patients without a thors conclude that methylprednisolone cannot be recom- natural tenodesis, flexor pollicis longus (FPL) tenodesis mended for routine use in acute nonpenetrating SCIs and that is surgically created by securing the proximal end of the prolonged administration (48 hours) of high-dose steroids is tendon to the distal radius. To preserve thumb interpha- not without risk and may be harmful to the patient. Until langeal joint flexion, a screw is inserted through the dis- more evidence is forthcoming, methylprednisolone should be tal tip of the thumb and placed across the interpha- considered to have investigational (unproven) status only. langeal joint. When possible, transfer of an active muscle to the FPL will also provide lateral pinch to the finger Kirshblum S, Campagnolo D, DeLisa J: Spinal Cord flexors and will provide better function. To provide fin- Medicine. Philadelphia, PA, Williams and Wilkins, 2002. ger flexion in the C6 patient, tendon transfer to the flexor digitorum profundus provides grasp and a firm This comprehensive resource of SCI medicine encom- surface for lateral pinch. The flexor carpi radialis, prona- passes traumatic and nontraumatic disorders affecting the spi- tor teres, and extensor carpi radialis longus have all nal cord. All aspects of the spinal cord including anatomy, epi- been used for lateral pinch and finger flexors. demiology, classification, treatment and complications for acute SCI, comprehensive rehabilitation topics, and aging with Patients with C7 tetraplegia lack finger and thumb SCI are reviewed. Various nontraumatic disorders of the spi- flexion and intrinsic hand musculature. Transfer of the nal cord including motor neuron disorders, multiple sclerosis, brachioradialis to the FPL can achieve restoration of and postpolio syndrome are also covered. thumb flexion. Restoration of finger flexion can be achieved through transfer of the extensor carpi radialis longus, flexor carpi ulnaris, or pronator teres to the flexor digitorum profundus. Annotated Bibliography Burns AS, Ditunno JF: Establishing prognosis and maxi- National Spinal Cord Injury Statistical Center: Spinal mizing functional outcomes after spinal cord injury: A Cord Injury: Facts and Figures at a Glance, University American Academy of Orthopaedic Surgeons 627

Spinal Cord Injury Orthopaedic Knowledge Update 8 of Alabama at Birmingham, Birmingham, AL. Available Barbeau H, Ladouceur M, Norman K, Pepin A, Leroux at: www.spinalcord.uab.edu. Accessed May 2001. A: Walking after spinal cord injury: Evaluation, treat- ment, and functional recovery. Arch Phys Med Rehabil The National Spinal Cord Injury Database has been in ex- 1999;80:225-235. istence since 1973 and includes data from an estimated 13% of new SCI patients in the United States. Since its inception, 25 Bracken MB, Shepard MJ, Collins WF, et al: A random- federally funded Model SCI Care Systems have contributed ized, controlled trial of methylprednisolone or naloxone data to the National SCI Database. As of July 2004, the data- in the treatment of acute spinal cord injury: Results of base contained information on 22,992 patients who sustained the Second National Acute Spinal Cord Injury Study. traumatic SCI. N Engl J Med 1990;322:1405-1411. Papadopoulos SM, Selden NR, Quint DJ, Patel N, Bracken MB, Shepard MJ, Collins WR Jr, et al: Methyl- Gillespie B, Grube S: Immediate spinal cord decompres- prednisolone or naloxone treatment after acute spinal sion for cervical spinal cord injury: Feasibility and out- cord injury: One-year follow-up data: Results of the come. J Trauma 2002;52:323-332. second National Acute Spinal Cord Injury Study. J Neurosurg 1992;76:23-31. Ninety-one consecutive patients with acute, traumatic cer- vical SCI (1990-1997) were prospectively studied to determine Bracken MB, Shepard MJ, Holford TR, et al: Adminis- the effect of immediate surgical spinal cord decompression on tration of methylprednisolone for 24 or 48 hours or tir- neurologic outcome. The authors concluded that immediate ilazad mesylate for 48 hours in the treatment of acute spinal column stabilization and spinal cord decompression, spinal cord injury: Results of the Third National Acute based on MRI, may significantly improve neurologic out- Spinal Cord Injury Randomized Controlled Trial. Na- comes. tional Acute Spinal Cord Injury Study. JAMA 1997;277: 1597-1604. Sekhon LH, Fehlings MG: Epidemiology, demographics, and pathophysiology of acute spinal cord injury. Spine Brunette DD, Rackswold GL: Neurologic recovery fol- 2001;26(suppl 24):S2-S12. lowing rapid spinal realignment for complete cervical spinal cord injury. J Trauma 1987;27:445-447. This review examines the epidemiology, demographics, and pathophysiology of acute SCI. The authors also discuss future Cotler HB, Miller LS, DeLucia FA, Cotler JM, Dayne goals of increasing understanding of both primary and second- SH: Closed reduction of cervical spine dislocations. Clin ary mechanisms of injury, the roles of calcium, free radicals, so- Orthop 1987;214:185-199. dium, excitatory amino acids, vascular mediators, and apop- tosis. Delamarter RB, Sherman JE, Carr JB: Cauda equina syndrome: Neurologic recovery following immediate, Winslow C, Bode RK, Felton D, Chen D, Meyer PR Jr: early, or late decompression. Spine 1991;16:1022-1029. Impact of respiratory complications on length of stay and hospital costs in acute cervical spine injury. Chest Dolan EJ, Tator CH, Endrenyi L: The value of decom- 2002;121:1548-1554. pression for acute experimental spinal cord compression injury. J Neurosurg 1980;53:749-755. This article attempts to determine if respiratory complica- tions experienced during the initial acute-care hospitalization Frisbie JH: Fractures after myelopathy. J Spinal Cord in patients with acute traumatic cervical spinal injury are more Med 1997;20:66-69. important determinants of the length of stay and total hospital costs than level of injury. A retrospective analysis of an incep- Galandiuk S, Raque G, Appel S, Polk HC Jr: The two- tion cohort (413 patients) for the 5-year period from 1993 to edged sword of large-dose steroids for spinal cord 1997 was performed. The results showed that both mean trauma. Ann Surg 1993;218:419-425. length of stay and hospital costs increased monotonically with the number of respiratory complications experienced. The au- George ER, Scholten DJ, Buechler CM, Jordan-Tibbs J, thors concluded that the number of respiratory complications Mattice C, Albrecht RM: Failure of methylprednisolone experienced during the initial acute-care hospitalization for to improve the outcome of spinal cord injuries. Am Surg cervical spine injury is a more important determinant of 1995;61:659-663. length of stay and hospital costs than level of injury. Classic Bibliography Green D: Prevention of thromboembolism after spinal cord injury. Semin Thromb Hemost 1991;17:347-350. American Spinal Injury Association: International Stan- Guha A, Tator CH, Endrenyi L, Piper I: Decompression dards for Neurological Classification of Spinal Cord In- of the spinal cord improves recovery after acute experi- jury, revised 2002. Chicago, IL, American Spinal Injury mental spinal cord compression injury. Paraplegia 1987; Association, 2002. 25:324-339. 628 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 51 Spinal Cord Injury Merli GJ, Crabbe S, Doyle L: Mechanical plus pharma- Stover SL, Fine PR: The epidemiology and economics of cological prophylaxis and deep vein thrombosis in acute spinal cord injury. Paraplegia 1987;25:225-228. spinal cord injury. Paraplegia 1992;30:558-562. Tarlov IM, Klinger H: Spinal cord compression studies: Moberg EA: The present state of surgical rehabilitation II. Time limits for recovery after acute compression in for the upper limb in tetraplegia. Paraplegia 1987;25: dogs. AMA Arch Neurol Psychiatry 1954;71:271-290. 351-356. Tator CH, Duncan EG, Edmond VE, Lapczak LI, An- Nesathurai S: Steroids and spinal cord injury: Revisiting drews DE: Complications and costs of management of the NASCIS II and NASCIS III Trials. J Trauma 1998; acute spinal cord injury. Paraplegia 1993;31:700-714. 45:1088-1093. Vaccaro AR, An HS, Betz RR: The management of Parsons KC, Lammerts DP: Rehabilitation in spinal acute spinal trauma: Prehospital and in-hospital emer- cord disorders: 1. Epidemiology, prevention, and system gency care. Instr Course Lect 1997;46:113-125. care of spinal cord disorders. Arch Phys Med Rehabil 1991;72(suppl):S293-S294. Vaccaro AR, Daugherty RJ, Sheehan TP, et al: Neuro- logic outcome of early versus late surgery for cervical Staas WE, Formal CS, Freedman MK, et al: Spinal cord spinal cord injury. Spine 1997;22:2609-2613. injury and spinal cord injury medicine, in DeLisa JA (ed): Rehabilitation Medicine Principles and Practice, ed Waters RL, Adkins RH, Yakura JS: Motor and sensory 3. Philadelphia, PA, Lippincott Raven, 1998, pp 1259- recovery following complete tetraplegia. Arch Phys Med 1292. Rehabil 1993;74:242-247. American Academy of Orthopaedic Surgeons 629



Chapter 52 Miscellaneous Neurologic Diseases Guy W. Fried, MD Multiple Sclerosis Pain and dysesthesias can often be a prominent fea- ture of MS. More than half of the patients with MS have Multiple sclerosis (MS) is an inflammatory demyelinat- a history of an acute or chronic pain disorder. These ing disease of the central nervous system that causes symptoms are best treated with anticonvulsant or tricy- multiple focal lesions. The focal lesions and their neuro- clic antidepressant medications. When a patient has logic effects are progressive and difficult to predict. MS pain, evaluation for correctable causes such as carpal is twice as common in women than in men, is diagnosed tunnel syndrome, cervical myelopathy, and mechanical at an average age of 30 years, and is 10 times more prev- back pain is important. alent in northern geographic areas such as the United States and Canada than in Asia and Africa. MS is char- Spasticity is a velocity-dependent increase in resis- acterized by recurrent episodes of inflammation of the tance to a passive stretch. Potential complications in- myelin and it can affect any area in the central nervous clude reduced joint range of motion and contracture, system. The inflammation and immune response destroy poor hygiene, predisposition to decubitus, pain, and an the myelin, cause plaque formation, and disrupt nerve impaired ability to use volitional motor power, resulting conduction. The development and progression of MS in functional impairment. Spasticity can be beneficial in usually follows a set pattern according to the history of some instances. Spasticity of the knee extensors can as- exacerbations and remissions. Patients may suffer exac- sist with stability during transfers and ambulation. The erbations following physical and emotional stressors; for Modified Ashworth Scale is a frequently used rating sys- example, the stress of a surgical procedure. Good prog- tem for spasticity (Table 1). nostic indicators for MS include having no motor find- ings at the time of presentation, resolution of early If spasticity interferes with function, treatment may flare-ups, an age younger than 30 years at onset, and be considered. Before treatment is initiated, however, having limited cerebellar and pyramidal findings after 5 an increase in spasticity should be investigated for an years. underlying cause. Any noxious stimulation such as blad- der distension, bowel impaction, or an ingrown toenail Because of the complexity of its symptoms, the dif- may increase a patient’s spasticity. The initial treatment ferential diagnosis of MS is broad. MS may appear as a for spasticity is usually oral medications such as ba- single subtle symptom or as a more significant constella- clofen, benzodiazepines, tizanidine, and dantrolene sodi- tion of symptoms. The differential diagnosis includes um; however, these medications can have a sedating ef- central nervous system tumors, cerebrovascular acci- fect and may contribute to fatigue. Other treatments dent, anterior horn cell disease, myasthenia gravis, and include botulinum toxin serotypes A and B, which are collagen vascular diseases, as well as the secondary ef- given as an intramuscular injection that binds at recep- fects of Lyme disease and human immunodeficiency vi- tor sites inhibiting the release of acetylcholine. Accord- rus (HIV). Currently, MRI is the most accurate tool to ing to a 2001 study, botulinum toxin injections can be diagnose MS, with positive findings in 72% to 95% of quite useful in diminishing focal spasticity, and do not patients. White matter plaques are a characteristic find- have any cognitive or fatigue-related adverse effects. ing. Gadolinium contrast can help distinguish old from However, the injections potentially can lead to tempo- new lesions. Lumbar puncture may also be useful be- rary weakness and the cost per injection can begin at cause spinal fluid characteristics may show increased several hundred dollars. Intrathecal baclofen also can be gamma globulin in 60% of patients with definite MS. useful in controlling severe lower extremity spasticity. A The oligoclonal band may be seen in the gamma globu- surgically implanted pump allows precise titration to de- lin region on gel electrophoresis. liver varying doses of baclofen to correspond with the need for spasticity control throughout the day. The in- American Academy of Orthopaedic Surgeons 631

Miscellaneous Neurologic Diseases Orthopaedic Knowledge Update 8 TABLE 1 | Modified Ashworth Scale lengthening procedures followed by postoperative cast- ing can allow better range of motion. Hip flexion Scale Description contracture can accompany knee flexion contractures. 0 No increase in muscle tone Iliopsoas tenotomy may be useful if standard range-of- 1 Slight increase in muscle tone, manifested as a catch-and- motion techniques fail. release or by minimal resistance at the end of range of Parkinson’s Disease motion 1+ Slight increase in muscle tone, manifested by a catch, Parkinson’s disease is a chronic, degenerative, central followed by minimal resistance throughout the remainder nervous system movement disorder characterized by (less than half) of the range of motion resting tremor and bradykinesia. Dementia may also de- 2 More marked increase in muscle tone throughout most of velop in about 10% to 15% of patients. In Parkinson’s the range of motion, but the affected limb is easily moved disease, the site of pathology is the basal ganglia and ex- 3 Considerable increase in muscle tone; passive range of trapyramidal motor system that is responsible for con- motion difficult trolling upright posture, muscle tone, coordination, and 4 Affected limb is rigid the initiation of automatic movements in the face and body. There is also a deficiency of dopamine, which al- (Reproduced with permission from Black-Schaefer R: Stroke (Young), in Frontera W, Silver lows acetylcholine to become predominant and precipi- J (eds): Essentials of Physical Medicine. Philadelphia, PA, Hanley and Belfus, 2002, pp tate tremor. The classic tremor occurs at rest and is 784-792.) abolished by movement; therefore, the disease is not ini- tially disabling. The major motor disability is bradykine- trathecal baclofen may allow the patient to take fewer sia and akinesia as evidenced by difficulty initiating oral medications and reduce the overall side effect pro- movements and decreased associated motions. Clinical file. observation will show a patient having moderate diffi- culty rising from a chair, often needing to use their arms Orthotic treatment to support ankle and foot posi- to push off. The patient will assume a forward-flexed tioning as well as supportive management for impaired standing posture and will walk with a slow, moderately functional abilities tend to be the primary rehabilitative wide-based gait with short steps. Patients may exhibit a focus. Orthotic treatment may or may not be necessary festinating gait, appearing to be falling forward as they because of the variable presentation of MS. The pa- start off slowly and then move faster. The patients show tient’s degree of sensation, tone, and muscle strength, es- poor postural reflexes in which they do not reorient pecially at the knee and ankle, must be considered. their balance to environmental changes. Cogwheeling, Orthoses are typically made of metal, plastic, or a com- which represents a basal ganglia disorder of tone, is elic- bination of these materials. The molded plastic ankle- ited by passive flexion and extension of a muscle, allow- foot orthosis (AFO), which immobilizes the ankle in ing the examiner to feel repetitive stops during range- gait, is the most commonly used. Plastic AFOs are of-motion testing. Patients with Parkinson’s disease may lighter and more easily concealed, which frequently also have a hypokinetic dysarthria, which presents as leads to better patient acceptance. Fluctuating edema is limited intonation and affect. Deficits in posture, bal- better accommodated in a metal orthosis because it ance, and tone may lead to frozen joints and falls that does not closely approximate the skin and therefore al- create most of the injuries (such as fractures) requiring lows the limb more flexibility. A limb with poor sensa- orthopaedic intervention. Postural instability, bradykine- tion is also better suited to a metal orthosis because it sia, and rigidity are the major predictors of falls. Patients can be manufactured with a soft leather shoe or inner with Parkinson’s disease can improve their ability to lining to avoid skin breakdown. A metal AFO also can move with exercises emphasizing range of motion, bal- allow more adjustments for ankle joint control. ance, gait, and fine motor dexterity; gains can be lost if regular exercise is stopped. Maintenance exercises are The location of the spasticity and how well it is con- also useful for management of rigidity and bradykinesia. trolled may determine the necessity of surgical proce- dures. The goal of surgical orthopaedic intervention is to The mainstay treatment of symptoms of Parkinson’s improve function and correct deformity. The split ante- disease is medication. Centrally acting anticholinergic rior tibial tendon transfer procedure is used to reduce medications can decrease tremors and saliva produc- excessive inversion of the foot. The tendon of the tibialis tion. Amantadine potentiates the action of dopamine anterior is surgically split, allowing a portion to be at- and may help with akinesia and rigidity. Levodopa has tached to the cuneiform and cuboid bones to generate been found to be effective at improving bradykinesia an eversion force. MS will also frequently lead to an tremor and rigidity when added to carbidopa. The com- equinovarus foot, which interferes with ambulation and bination of levodopa and carbidopa allows more medi- may require surgery. Knee flexion contractures can also cation to enter the circulatory system and cross the occur with severe spasticity. Orthopaedic hamstring 632 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 52 Miscellaneous Neurologic Diseases blood-brain barrier. It has been noted that a low protein with dysesthesias. The peripheral neuropathy can be re- diet allows for more consistent results with levodopa. versible if vitamin B12 is given early in the disease pro- Levodopa has also been noted to improve the hypoki- cess. netic dysarthria, allowing for faster and more natural lip movement and thereby improving speech intelligibility. Paraproteinemias including multiple myeloma, amy- loidosis, lymphoma, Waldenström’s macroglobulinemia, Peripheral Polyneuropathy chronic lymphocytic leukemia, and nonmalignant gam- mopathy may also lead to a neuropathy. Frequently this Peripheral polyneuropathy is a common condition in or- is a diffuse distal symmetrical problem. Multiple my- thopaedic patients. The lower motor neurons of the pe- eloma most commonly occurs in patients between 40 ripheral nervous system may be damaged in a variety of and 70 years of age. A distal sensorimotor involvement diseases. Patients often will have abnormal sensation will present in about 5% of the patients with multiple that may be described as dull, prickling, numbing, or the myeloma. Radicular pain may occur with or without feeling of pins and needles. In addition, autonomic ner- vertebral fractures. Many demyelinating neuropathies vous system involvement may produce gastroparesis, with a diffuse symmetric pattern are inherited; for ex- postural hypotension, and problems with regulation of ample, Charcot-Marie-Tooth disease that presents with heart rate. It is important to start with a detailed history a progressive symmetric distal muscular atrophy. and physical examination evaluating weakness, atrophy, areflexia, and sensory loss. Physical assessment deter- HIV is commonly associated with peripheral poly- mines whether involvement is in a focal region of the neuropathy. Fifty percent of patients with acquired im- body associated with an entrapment site such as carpal munodeficiency syndrome show symptoms of a periph- tunnel syndrome or whether it is a diffuse peripheral eral polyneuropathy. The HIV infection may produce a condition. Electrodiagnostics can provide an added ben- neuropathy, which is clinically indistinguishable from efit in helping to clarify the nerve disease process. Nee- Guillain-Barré syndrome. The presentation of the demy- dle electromyography and nerve conduction velocity elinative neuropathy occurs early in the HIV infection studies can help determine whether the neuropathic and may in fact be the presenting symptom. Guillain- process is predominantly axonal, demyelinating, or a Barré syndrome is the most common disease producing combination of both. These studies can also determine an acute generalized paralysis from an inflammatory de- whether the findings involve primarily motor or sensory myelinating polyneuropathy. Patients present with distal nerves, and whether they are symmetric versus multifo- paresthesias and then a generalized weakness that cal. A careful family history of primary family members progresses. Cranial nerve involvement is not uncom- can evaluate for inherited neuropathies, which can ap- mon, with the facial nerve being affected in up to one pear without a readily apparent clinical etiology. half of the patients. Early mortality in Guillain-Barré syndrome is related to respiratory failure, and up to Diabetes is the most common cause of peripheral 30% of patients may require mechanical ventilation. Au- neuropathy. It affects multiple organ systems, including tonomic nervous system involvement will result in diffi- the peripheral nervous system. The incidence of periph- culties regulating blood pressure, heart rate, and body eral neuropathy in diabetic patients depends largely on temperature as well as bowel and bladder function. how it is defined. If it is defined by patient symptoms, Overall, about 16% of patients with Guillain-Barré syn- about half of the individuals are affected. If electrodiag- drome will be left with a degree of permanent disability. nostic characteristics are considered, the incidence in- Electromyogram studies of the amplitude of the com- creases to 90%. Peripheral neuropathy is also associated pound of motor action potential have a strong predic- with end stage renal disease. Studies indicate that at the tive value for ambulation. Children have a much greater time dialysis is initiated, as many as 65% of the patients potential for recovery. have a peripheral neuropathy; axonal damage is more common than demyelination. The specific etiology is un- With all the neuropathies a thorough patient history clear but it appears to be related to toxin buildup be- and physical examination followed by a search for revers- cause hemodialysis, peritoneal dialysis, and renal trans- ible causes are critical. Musculoskeletal treatment empha- plantation have led to an improvement in symptoms sizes maintaining basic health status by monitoring auto- and electrodiagnostic study results. Chronic alcohol in- nomic functions including blood pressure, temperature, gestion leads to a similar type of peripheral neuropathy and breathing. Musculoskeletal supports include a condi- affecting the axons and leading to significant demyelina- tioning endurance program. Musculoskeletal weakness tion. Abstinence from alcohol may improve symptoms. can be addressed through range-of-motion activities and Pernicious anemia is frequently caused by a deficiency orthotic devices such as a lightweight plastic AFO to of gastric intrinsic factor leading to a malabsorption of maintain function. Surgical treatment consisting of Achil- vitamin B12 from the ileum. In patients with pernicious les tendon lengthening, split anterior tibial tendon trans- anemia, an axonal peripheral neuropathy is common fer, and plantar fascial release may prevent later problems. Before performing surgical procedures, it should be deter- mined whether the underlying process is progressive, such American Academy of Orthopaedic Surgeons 633

Miscellaneous Neurologic Diseases Orthopaedic Knowledge Update 8 as Charcot-Marie-Tooth disease, whether there are re- Joy JE, Johnston RB (eds): Multiple Sclerosis: Current versible factors as in vitamin B12 deficiency, or ominous Status and Strategies for the Future. Washington, DC, Na- factors such as HIV infection. tional Academy Press, 2001, pp 29-69. Postpolio Syndrome This review article is an excellent overview that highlights the pathophysiology, diagnosis, prognosis, and treatment of Postpolio syndrome occurs in patients with a history of multiple sclerosis. acute polio. It has been estimated that 25% to 60% of the patients who had acute polio may experience latent Keenan MA, Esquenazi A, Mayer NH: The use of labo- effects of the disease. The characteristics of postpolio ratory gait analysis for surgical decision making in per- syndrome include musculoskeletal pain, fatigue, new sons with upper motor neuron syndromes. Phys Med muscle weakness or atrophy, respiratory impairment, Rehabil State Art Rev 2002;16:249-261. cold intolerance, and a decline in the ability to perform activities of daily living. The specific cause of postpolio A description of laboratory gait analysis and its use in syndrome is unknown; the etiology has been attributed identifying muscle groups causing spasticity is presented. The to pathophysiologic and functional causes. Pathophysio- use of this information for presurgical planning is discussed. logic causes include chronic poliovirus infection, death of the remaining motor neurons with aging, premature Rammohan KW: Axonal injury in multiple sclerosis. aging, damage to the remaining motor neurons caused Curr Neurol Neurosci Rep 2003;3:231-237. by increased demands or secondary insults, and an immune-mediated syndrome. Functional etiologies for The pathophysiology and pathogenesis of MS are dis- postpolio syndrome include greater energy expenditure cussed. Axonal injury is recognized as an early occurrence in as a result of weight gain and muscle weakness caused the inflammatory lesions of MS. Neurologic functional impair- by disuse or overuse. ment correlates best with axonal damage. A mild conditioning program for patients with post- Shapiro RT: Pharmacologic options for the management polio syndrome may be beneficial while avoiding any of multiple sclerosis symptoms. Neurorehabil Neural overuse or excessive fatigue that can be detrimental. Repair 2002;16:223-231. Most orthopaedic needs are based on joint, muscle, or back pain. Many patients require revision of orthotic This article reviews pharmacologic management of MS. devices such as braces, canes, and crutches or new Immunomodulatory drugs that control the underlying disease orthotic devices to treat new symptoms. Common issues process but do not cure MS are reviewed. The article empha- include genu recurvatum, knee pain, back pain, degener- sizes that optimal disease treatment requires a multidisci- ative arthritis, or arthralgia. Surgery for scoliosis or frac- plinary approach combining medication, rehabilitation, and tures may also be necessary to treat new conditions. patient education. Annotated Bibliography Yablon SA: Botulinum neurotoxin intramuscular chemodenervation: Role in the management of spastic Multiple Sclerosis hypertonia and related motor disorders. Phys Med Rehabil Clin N Am 2001;12:833-874. Frohman EM: Multiple sclerosis. Med Clin North Am 2003;87:867-897. Botulinum neurotoxin intramuscular chemodenervation use is an important therapeutic tool in focal spasticity manage- MS is the most common disabling neurologic disease of ment. Botulinum toxin injections have been shown to be effec- young people. It affects up to 450,000 people in the United tive and safe. Techniques, dosage, targeted muscles, and func- States. Substantial advances have been made in diagnosis and tional goals are discussed in this review article. treatment over the past decade. This excellent review article helps in the formation of initial diagnostic and treatment Parkinson’s Disease plans. Samii A, Nutt JG, Ransom BR: Parkinson’s disease. Jin YP, de Pedro-Cuesta J, Huang YH, Soderstrom M: Lancet 2004;363:1783-1793. Predicting multiple sclerosis at optic neuritis onset. Mult Scler 2003;9:135-141. Parkinson’s disease is the most common serious move- ment disorder in the world, affecting about 1% of adults older This prospective study examines patients who develop def- than 60 years. This review article covers diagnosis, treatment, inite MS at the onset of optic neuritis. Correlations made with and pathogenesis. MRI and oligoclonal bands in cerebrospinal fluid aid in the di- agnosis. The study indicated a strong correlation between optic Peripheral Polyneuropathy neuritis leading to definite MS in patients with brain and spi- nal cord lesions. Cannon A, Fernandez Castaner M, Conget I, Carreras G, Castell C, Tresserras R: Type 1 diabetes mellitus in Catalonia: Chronic complications and metabolic control ten years after onset. Med Sci Monit 2004;10:CR185- CR190. 634 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 52 Miscellaneous Neurologic Diseases This review article confirms that diabetic microvascular LaBan MM, Martin T, Pechur J, Sarnacki S: Physical and complications including polyneuropathy and retinopathy were occupational therapy in the in the treatment of patient already present 10 years after the onset of diabetes. with multiple sclerosis. Phys Med Rehabil Clin N Am 1998;9:603-614. Postpolio Syndrome McDeavitt JT, Graziani V, Kowalske KJ, Hays RM: Neu- Jubelt B: Post-polio syndrome. Curr Treat Options romuscular disease: Rehabilitation and electrodiagnosis: Neurol 2004;6:87-93. 2. Nerve disease. Arch Phys Med Rehabil 1995;76:S10- S20. Postpolio syndrome describes the late manifestations that occur in patients 30 to 40 years after acute poliomyelitis, such Meythaler JM, DeVivo MJ, Braswell WC: Rehabilitation as new weakness, muscle pain, joint pain, peripheral nerve outcomes of patients who have developed Guillain- compression, fatigue, and cold intolerance. This review article Barré syndrome. Am J Phys Med Rehabil 1997;76:411- discusses the diagnosis and treatment plan. 419. Classic Bibliography Miller RG, Peterson GW, Daube JR, Albers JW: Prog- nostic value of electrodiagnosis in Guillain-Barré syn- Cheng Q, Jiang GX, Press R, et al: Clinical epidemiol- drome. Muscle Nerve 1988;11:769-774. ogy of Guillain-Barre syndrome in adults in Sweden in 1996-97: A prospective study. Eur J Neurol 2000;7:685- 692. American Academy of Orthopaedic Surgeons 635



Chapter 53 Traumatic Brain Injury and Stroke Barbara J. Browne, MD Jeanne G. Doherty, MD Epidemiology tween the severity of the skull fracture and the severity of the neurologic injuries. A cranial vault fracture may Traumatic brain injury is defined as any insult to the brain be linear or stellate, and depressed or nondepressed. A caused by an external force, causing temporary or perma- depressed skull fracture initially may be missed second- nent impairments in physical function, cognitive ability, ary to few or no neurologic symptoms. The mortality and/or disturbance of behavioral and emotional function. rate in individuals with a depressed skull fracture is These impairments may cause total or partial functional 11%. Approximately 11% of patients with a depressed disability and psychosocial maladjustment. Two million skull fracture will be left with permanent neurologic brain injuries occur in the United States each year. Ap- deficits. Depressed skull fractures can be further subdi- proximately 50,000 patients die from acute brain injury. vided into simple or closed (15%) and compound or open (85%). A simple fracture is not associated with a Leading causes of traumatic brain injury include mo- laceration. There is no evidence to suggest that surgical tor vehicle crashes (50%), falls (21%), gunshot wounds elevation of a simple, depressed skull fracture reduces (12%), and recreational injuries (10%). Alcohol is a fac- the incidence of seizures or improves neurologic deficits tor in approximately 60% of injuries across all age unless there is a skull fragment compressing the cere- groups. bral hemisphere. A compound, depressed skull fracture is associated with a scalp laceration. These types of skull Approximately 750,000 Americans suffer strokes fractures should be explored and surgically elevated to each year; nearly one third of these patients die. Those reduce the risk of central nervous system infection. A who survive experience significant levels of disability, basilar skull fracture increases the risk of meningitis with hemiparesis as the most common impairment. Only with a dural tear, pneumocephalus, cerebrospinal fluid 10% of stroke survivors experience a full recovery. An- fistula, and cranial nerve injury. other 10% fail to improve. The remaining 80% have varying degrees of neurologic impairment that will im- Secondary injuries include the effects of intracranial prove with rehabilitative intervention. pressure, cerebral edema, and hydrocephalus, which may cause cerebral ischemia and hypoxia of brain tissue. Mechanism of Injury They may also include brain herniation syndromes, which can cause significant damage to the brainstem. There are primary and secondary mechanisms of injury in traumatic brain injury. Primary injury occurs immedi- The two major mechanisms causing stroke are is- ately at the time of impact and is associated with chemia (80%) and hemorrhage (20%). These two groups acceleration-deceleration and rotational forces. Second- can be further subdivided by location and cause. Ischemic ary injury is the neurochemical and physiologic sequelae stroke has three main mechanisms: thrombosis, embolism, of the primary brain insult, which occurs over hours to and systemic hypoperfusion. Each of these mechanisms days after the initial injury. can result from various underlying pathologic conditions. Hemorrhages are most commonly associated with uncon- Primary injury includes skull fracture, intracranial trolled hypertension, aneurysms, and arteriovenous mal- hemorrhage, cortical contusion, diffuse axonal injury (a formations. significant injury to the white matter of the brain), and penetrating injury. The two basic types of skull fractures Types of Deficits are those of the cranial vault and the basilar skull. Frac- tures of the occipital condyles also may occur. Intracranial Stroke and brain injury can cause mobility and self-care hemorrhages include epidural and subdural hematomas deficits and behavioral, emotional, and cognitive dys- and intracerebral and subarachnoid hemorrhages. Although skull fractures increase the risk of seizure and intracranial hematoma, there is no correlation be- American Academy of Orthopaedic Surgeons 637

Traumatic Brain Injury and Stroke Orthopaedic Knowledge Update 8 function. Certain generalizations regarding types of def- Complications icits can be made based on the anatomic location of in- jury in the brain. Injuries involving the cerebral Spasticity hemispheres can result in contralateral paralysis, sen- sory changes, and visual field losses. Paralysis of the arm Spasticity is discussed in detail in chapter 52. tends to be more pronounced with middle cerebral ar- tery lesions, whereas lower limb weakness is most pro- Contractures nounced with anterior cerebral artery lesions. Frontal lobe injury often causes impairments of insight, judg- A contracture is defined as a fixed loss of passive joint ment, logical reasoning, problem solving, memory, and range of motion (ROM) secondary to pathology of con- higher level executive functioning. It may also cause ap- nective tissue, tendons, ligaments, muscles, joint capsule, athy, withdrawal from social interaction, emotional and/or cartilage. Contractures occur in up to 84% of pa- swings, impulsiveness, and confabulation. Parietal lobe tients and can be classified as arthrogenic, soft-tissue, or injuries often cause agnosia (inability to recognize sen- myogenic. Arthrogenic contractures are caused by pa- sory stimuli), apraxia (inability to perform purposeful thology of the intrinsic joint components, and cause re- movement despite adequate motor ability), aphasia, striction of ROM in all planes. Soft-tissue contractures visual-spatial disorders, and hemispatial neglect. Injury result in shortening of tendons, ligaments, and skin, to the dominant hemisphere can cause language and causing restriction of movement in one plane. Myogenic speech disorders. Nondominant hemispheric injury may contractures can be further classified as intrinsic or ex- cause deficits such as anosognosia (loss of awareness of trinsic. Intrinsic myogenic contractures are caused by a one’s own deficits) and constructional apraxia (inability primary disorder of muscle fibers, such as muscular dys- to reproduce drawings or assemble and build structures trophy. In extrinsic myogenic contractures the muscle it- despite adequate motor ability). Emotional dysfunction self is histologically normal. Such contractures are sec- such as depression and indifference may occur. Tempo- ondary to muscles being placed in a shortened position ral lobe injury may cause disturbances in behavior, for extended periods of time such as occurs in brain in- memory, and cognition. Dominant hemisphere injury jury. Factors that contribute to the occurrence of con- may cause fluent aphasia, alexia, and agraphia (inability tractures include spasticity, immobility, prolonged bed to express thoughts in writing). Anxiety, depression, rest, weakness, improper positioning, pain, and hetero- rage, and fear also may occur. Occipital lobe injury may topic ossification (HO). Muscles such as the iliopsoas, cause visual impairment or occipital blindness (acting gastrocnemius, hamstrings, biceps, and tensor fascia lata sighted despite blindness). Brainstem stroke generally that cross two joints are at greatest risk of contracture. spares cognitive and language function but often shows Common locations in the lower extremity for contrac- diverse symptoms. Impairments can involve both ipsilat- tures include ankle plantar flexors, hip flexors, and knee eral and contralateral functions, cranial nerve dysfunc- flexors. Common locations for contractures in the upper tion, ataxia, vertigo, and dysphagia. extremity are elbow flexors/supinators and shoulder adductors/internal rotators. In the early period after a stroke, the affected limbs are often flaccid with an absence of deep tendon reflexes. The most important aspect of treatment of contrac- Over several weeks, a progression from flaccidity to spas- tures is prevention. Early mobilization, daily ROM exer- ticity to normal tone may occur. Motor return frequently cises, stretching, and the use of splints and orthotic de- begins as a synergistic contraction of multiple limb mus- vices are essential for preventing contractures. Proper cles rather than isolated action. Flexor activity predomi- positioning in bed and the wheelchair must also be ad- nates in the upper limb. A common pattern is scapular re- dressed. To avoid knee and hip flexion contractures in traction and depression, shoulder adduction with internal bed, pillows should not be placed under the knees, and rotation, forearm pronation, and flexion at the elbow, lying in the prone position also can be helpful. To avoid wrist, and fingers. Extensor overactivity is predominant in extreme shoulder adduction and internal rotation, pil- the lower limb with adduction and internal rotation at the lows should be placed to keep the shoulder in a partially hip, extension at the knee, and plantar flexion at the ankle abducted and externally rotated position. Elbows should with supination at the foot. The entire recovery process is not be positioned in flexion and supination. Resting variable and may halt at any stage. Early motor recovery night splints and bivalved casting can be used as a pre- is usually seen in proximal muscles before distal or iso- ventive measure. Ankle plantar flexion contractures are lated muscle movement. Maximal neurologic and func- common but preventable. In bed, the use of ankle-foot tional recovery has been shown to occur within 12 weeks orthoses ideally placed at 90° can help to prevent these for most patients undergoing standard inpatient rehabil- contractures. In addition, there are many wheelchair itation. modifications that can be used to alter a patient’s posi- tion and assist in preventing contractures. To encourage normal lordosis of the lumbar spine and kyphosis of the thoracic spine, the pelvis should be placed in a slightly anterior tilted position. Armrests and lapboards are 638 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 53 Traumatic Brain Injury and Stroke used to prevent shoulder contractures. Reclining the Shoulder Pain back support 10° and placing lateral trunk supports as- sists in trunk stabilization and proper alignment. Exten- Up to 85% of people with hemiplegia experience shoul- sions or hip blocks placed laterally keep the pelvis in a der pain. Shoulder spasticity and subluxation are among symmetrical position and align the lower extremities. the most frequent causes of pain. Additional factors in- Leg straps prevent adduction of the lower extremities. clude adhesive capsulitis, impingement syndrome with Footrest height can be adjusted to properly position the rotator cuff injury, complex regional pain syndrome ankle, knee, and hip. Despite all efforts to prevent con- type 1 (CRPS 1), and brachial plexopathy. Effective tractures they may still develop. If so, treatment mea- treatments to reduce spasticity-related muscle imbal- sures should be initiated immediately. Treatment in- ance include electromyogram biofeedback with relax- cludes physical, medical, and surgical intervention. A ation exercises, botulinum toxin, and phenol blocks. significant aspect of physical intervention is an aggres- Shoulder subluxation has been implicated as a contrib- sive stretching program with sustained stretching tech- uting factor in pain, limited ROM, and function. The use niques. To correctly stretch a joint, it is positioned at the of arm slings can reduce pain and subluxation in some limit of ROM and sustained in that position. Caution patients and may also improve gait stability by limiting should be used with patients who have significant os- detrimental displacement of the body’s center of gravity teoporosis so that fractures are avoided. Before stretch- seen in the hemiparetic gait. However, sling use can also ing, the use of therapeutic heat including ultrasound can result in increased flexor tone that may lead to contrac- be very beneficial. Patients with impaired sensation ture formation, and may promote disuse of the extrem- should be monitored closely. Serial casting applied to a ity. Wheelchair lap trays or arm boards provide support prestretched limb is a common treatment method for but may also overcorrect the subluxation and lead to joint contracture. The joint is held at its initial limit of impingement syndromes. Corticosteroid injections can ROM. Casts are periodically removed and new casts be an effective treatment for adhesive capsulitis. Other placed after increasing joint ROM by 5° to 10°, the new useful adjuncts include transcutaneous electrical nerve limit of ROM. The skin must be monitored for break- stimulation to reduce subluxation and pain. Current tri- down. Dynamic splints, which have movable parts to als of percutaneous intramuscular stimulation show counter contracting forces, are an alternative to serial promise for enhanced efficacy. Pain that is thought to casting. Medical treatment includes maximizing treat- originate centrally or related to CRPS 1 may respond to ment of spasticity and pain with modalities and medica- gabapentin, tricyclic antidepressants, oral steroids, or tion (see chapter 52). Surgical intervention is reserved stellate ganglion blocks. for patients who are refractory to conservative treat- ment. Options include joint manipulation, tendon re- Systemic Complications lease, tendon lengthening, and joint capsule release. Complications that can occur following tendon length- Dysphagia resulting in aspiration pneumonia occurs in ening include reduction of muscle strength and altered 20% of stroke survivors and up to 45% of traumatic ROM. There is also a tendency for tendon shortening to brain injury survivors. A video fluoroscopic swallow recur. Postoperative therapy is a key component to en- study provides additional sensitivity and identifies most sure the most favorable outcome. cases of dysphagia with aspiration. Factors that increase the risk of aspiration pneumonia include nasogastric Skin Conditions feeding, tracheostomy, lethargy, emesis, and reflux. Spe- cialized diets often involve thickened liquids with soft or Skin breakdown and pressure ulcers are preventable pureed solids. Patients believed to be at high risk for as- complications following traumatic brain injury and piration should have enteral feedings. A gastrostomy or stroke. Risk factors include impaired cognition, de- jejunostomy tube is inserted if prolonged enteral feed- creased mobility in bed, diaphoresis, incontinence, infec- ing is anticipated. Malnutrition is a possible complica- tion, diabetes, malnutrition, anemia, muscle atrophy, and tion of dysphagia. impaired sensation. Spasticity and joint contractures are significant contributing factors. The common mecha- Urinary dysfunction is often seen following stroke nisms for skin involvement include pressure, shear, mac- and brain injury. Complications include urinary tract in- eration, and friction. Preventive treatment includes fection, neurogenic bladder, and less frequently, neph- proper positioning, timely turning in bed, weight shifts rolithiasis and urethral stricture. in the wheelchair, minimizing excessive perspiration and urinary and fecal incontinence, proper transfer tech- Esophagitis, gastritis, ulcers, gastrointestinal hemor- niques, adequate nutrition, treatment of medical condi- rhage, pancreatitis, diarrhea, and constipation may also tions such as diabetes and anemia, and appropriate develop. An abnormal liver function test result is a com- treatment of spasticity and joint contractures. mon finding after brain injury. It may be drug induced or related to trauma and often is influenced by some premorbid factor. American Academy of Orthopaedic Surgeons 639

Traumatic Brain Injury and Stroke Orthopaedic Knowledge Update 8 TABLE 1 |Brooker Classification Scale for Heterotopic reational drug use. Previously there has been contro- Ossification of the Hip versy over the need for prophylactic treatment of post- traumatic seizures. It has been shown that prophylactic Class Description treatment is not indicated for more than 1 week after I Islands of bone with soft tissue traumatic brain injury unless there is documented sei- II Bone spurs from the pelvis or proximal femur, leaving at zure activity following injury, a history of seizure disor- der, or multiple risk factors. A seizure occurring 2 weeks least 1 cm between bone surfaces or more after stroke probably represents scar formation III Bone spurs from the pelvis or proximal femur, reducing and is usually treated with long-term prophylaxis. the space between opposing surfaces to less than 1 cm IV Bone ankylosis of the hip (Reproduced with permission from Blount PJ, Bockenek WL: Heterotopic ossification, in Heterotopic Ossification Frontera W, Silver J (eds): Essentials of Physical Medicine. Philadelphia, PA, Hanley and Belfus, 2002, pp 569-574.) HO is a musculoskeletal complication that may occur following traumatic brain injury and less frequently af- Atelectasis, pneumonia, deep venous thrombosis ter stroke. HO is described as new bone formation in (DVT), pulmonary embolism, and pneumothorax are nonskeletal tissue, located periarticularly. HO is not spe- possible complications after stroke and traumatic brain cific to traumatic brain injury and stroke; it also can de- injury. The more severely affected patients will require velop following a spinal cord injury, burn, fracture, total ventilator support and many will require a tracheo- joint arthroplasty, or trauma to muscle or joints. HO is stomy. Cardiovascular complications include hyperten- defined as neurogenic when it occurs secondary to trau- sion, arrhythmias, cardiomyopathy, myocardial infarc- matic brain, stroke, or spinal cord injury. The reported tion, and endocarditis. incidence of HO after traumatic brain injury varies de- pending on the study and ranges from 11% to 75%. DVT has been reported in up to 70% of unprotected There is an increased incidence to 76% in patients with stroke patients and in approximately 20% of patients af- severe traumatic brain injury. Approximately 20% to ter traumatic brain injury. Risk factors include bed rest, 30% of patients have clinically significant loss of ROM hemiplegia, flaccidity, older age, obesity, history of ma- from HO and 10% to 15% have complete ankylosis. The lignancy, and previous thrombosis. An additional risk Brooker classification system has been used to describe factor in the posttraumatic brain-injured population is HO of the hip (Table 1). lower extremity fracture. The risk of DVT appears low- est in patients capable of ambulating a distance of more Risk factors for developing HO subsequent to trau- than 100 feet. Differential diagnosis includes cellulites, matic brain injury include the presence of fractures, es- fracture, tumor, CRPS, and HO. A full discussion of pecially those of the long bones; prolonged coma (more treatment of DVT is found in chapter 51, Spinal Cord than 2 weeks); spasticity; and decreased ROM. HO usu- Injury. ally develops within 1 to 6 months of injury but it may develop as early as 2 weeks or as late as 12 months after Seizure Disorder injury. The clinical presentation of HO is variable. Most commonly it presents initially as decreased joint ROM A seizure occurs in 5% to 25% of stroke survivors. The or increased spasticity. A patient may also present with highest rates follow hemorrhagic, cortical, and embolic a low-grade fever, erythema, pain, swelling, or tender- strokes. Seizure disorder following traumatic brain in- ness. Less frequently HO may present with a nerve jury occurs in 1.5% of patients with mild injuries, 2.9% compression, vascular compression, or lymphedema. It with moderate injuries, and 17% of those with severe in- is most frequently found at the hips, then the shoulders juries. These posttraumatic seizures can be classified as and elbows, then the knees. In the hip, HO can form in- immediate (occurring within hours of the injury), early feromedially, anterolaterally, or posteriorly. In the knee (first detected within the first week of injury), and late it is usually found anteromedially, in the shoulder it usu- (occurring more than 1 week after injury). It is esti- ally forms inferomedially, and in the elbow it forms mated that 12% to 15% of new onset seizures following along the medial collateral ligament. Alternative diag- a traumatic brain injury occur 10 to 30 years after the noses include DVT, cellulitis, CRPS, septic joint, he- acute injury. Risk factors for posttraumatic seizures in- matoma, or tumor. The gold standard for diagnosing clude depressed skull fractures, prolonged posttraumatic HO is the three-phase radionuclide bone scan. Phase I amnesia, missile injuries with penetration and retained and II of the bone scan can detect the condition as early metal fragments, loss of consciousness for more than 24 as 2 to 3 weeks after the onset and phase III may be hours, focal neurologic signs on initial examination, in- positive in 4 to 8 weeks. The bone scan usually normal- tracerebral hemorrhage, diffuse brain contusion, cortical izes 7 to 12 months from the time of initial diagnosis. Al- injury with subcortical extension, advanced age, and rec- though its sensitivity is high, the disadvantage of using 640 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 53 Traumatic Brain Injury and Stroke the bone scan for diagnosing HO is its lack of specific- quate hemostasis, neurovascular bundle isolation, and ity. Serum alkaline phosphatase is another test used in adequate bone mass exposure are other measures to re- the diagnosis of HO, with elevated levels associated with duce morbidity. Postoperative complications include clinically significant HO. Normal levels range from 38 to hemorrhage, sepsis, and recurrence of HO. Postopera- 126 IU. Serum alkaline phosphatase levels begin rising tive prophylaxis to prevent recurrence includes medica- to the upper limits of normal within the first 2 weeks tions such as etidronate disodium or NSAIDs. Also, low and may begin to exceed normal values within the first dose radiation of 600 to 750 rads may be an option. 3 weeks from the initial onset of HO; peak levels are There have been some studies exploring the use of a reached at approximately 10 weeks and elevation may postoperative continuous passive ROM machine. Ther- persist for up to 6 months. Serum alkaline phosphatase apy for ROM begins when pain and swelling have sub- levels parallel the clinical course of HO. Elevated serum sided, usually 10 to 14 days postoperatively. alkaline phosphatase levels also are not specific. Levels may be elevated in clinical findings such as hepatic dys- Fractures function or fractures. If there is a suspicion of HO based on elevated serum alkaline phosphatase levels, a three- There are certain complications such as fractures and phase bone scan should be performed for confirmation. nerve injuries that occur specifically after traumatic brain injury. Fractures occur in approximately 34% of Treatment of HO includes physical therapy, medica- patients; 11% are estimated to be occult fractures. Com- tion, and surgical intervention. Physical therapy includes mon types include those of the pelvis, hip, knee, shoul- early aggressive ROM exercises, stretching, and joint der, and cervical spine fractures and dislocations. mobilization. There is no evidence to suggest that this Screening diagnostic studies including radiographs of intervention increases the formation of HO because of the cervical and thoracic spine, pelvis, hips, and long an inflammatory response. At times, manipulation under bones should be obtained in comatose patients, espe- anesthesia is necessary for active ROM of a joint that cially those with high velocity injuries. Bone scan should has not responded to conservative physical therapy. also be considered as a screening study. Treatment of Medication options for treatment of HO include eti- these fractures should include early fixation because of dronate disodium and nonsteroidal anti-inflammatory the strong possibility that these patients may eventually drugs (NSAIDs). Etidronate disodium is a biphospho- become agitated and confused. Delayed treatment of nate that limits ossification by blocking the formation of these fractures may become more difficult because of hydroxyapatite crystals. The prophylactic oral dose is 20 the increased risk for the development of hypertonicity mg/kg/day for 2 weeks, then 10 mg/kg/day for 10 weeks. and spasticity. Early stabilization is associated with The treatment oral dose is 20 mg/kg/day for 6 months or fewer pulmonary complications, decreased use of pain 20 mg/kg/day for 3 months, then 10 mg/kg/day for 3 medications, fewer joint contractures, decreased mortal- months. Adverse effects of etidronate disodium include ity, and shortened hospital stays. It also allows for ear- nausea, vomiting, diarrhea, and abdominal discomfort; it lier mobilization and thus facilitates earlier rehabilita- can also contribute to osteoporosis and impaired frac- tion. ture healing. NSAIDs reduce bone formation by inhibit- ing prostaglandin synthetase. They have been shown to Nerve Injury be effective in preventing HO following total hip ar- throplasty and HO resection. Indomethacin is the Peripheral nerve injuries occur in approximately 34% of NSAID most often used for treatment. NSAIDs have patients with severe traumatic brain injuries; 11% are not been proven specifically to decrease the incidence occult injuries. Causes include direct trauma, improper of neurogenic HO. positioning, postoperative complications, and HO. Cra- nial nerve injuries may also occur and are associated Indications for surgical intervention for HO include with the direct trauma. impaired positioning, which causes difficulty with sitting, lying, hygiene, ambulation, and activities of daily living; Assessment and ankylosed joints, which cause skin breakdown, pro- found pain, and progressive nerve compression. Some There are multiple assessment tools used to measure studies have indicated that patients with good neuro- both severity of brain injury and function after injury. muscular control in general have the best postoperative The Glasgow Coma Scale is the gold standard for mea- functional outcome. Those with a poor neurologic recov- suring severity of injury in the acute stage. One score to- ery and persistent spasticity have a higher incidence of taling from 3 to 15 is obtained based upon eye opening, recurrence and less functional improvement in the limb. verbal response, and best motor response (Table 2). In- The surgery may be a wedge or complete resection. It is jury is classified as severe if the score is 3 to 8, moderate essential to defer the surgery until the bone formation is from 9 to 12, and mild from 13 to 15. Loss of conscious- mature, at least 18 to 24 months from the initial diagno- ness for more than 6 hours is indicative of a severe in- sis, to limit excessive bleeding. Cautious dissection, ade- jury. Posttraumatic amnesia is memory loss following in- American Academy of Orthopaedic Surgeons 641

Traumatic Brain Injury and Stroke Orthopaedic Knowledge Update 8 TABLE 2 |Glasgow Coma Scale treatments include avoiding learned nonuse of the af- fected side and brain reorganization. Other promising Scale Eye Opening Verbal Response Motor Response treatments include treadmill gait training with body- 6 Obeys commands weight support, which can promote balance and gait ef- 5 Oriented Localizes to pain ficiency, and neuromuscular electrical stimulation. 4 Spontaneous Confused Withdraws from Annotated Bibliography 3 To speech Inappropriate pain Flexor posturing Epidemiology 2 To pain Incomprehensible Extensor posturing No response Petrilli S, Durufle A, Nicolas B, Pinel JF, Kerdoncuff V, 1 No response No response Gallien P: Prognostic factors in the recovery of the abil- ity to walk after stroke. J Stroke Cerebrovasc Dis 2002; (Reproduced with permission from Burke DT: Traumatic brain injury, in Frontera W, Silver J 11:330-335. (eds): Essentials of Physical Medicine. Philadelphia, PA, Hanley and Belfus, 2002, pp 806- 812.) This article presents a prospective study of 93 stroke pa- tients; factors predictive of future ambulation are identified. jury. A brain injury is mild if it lasts less than 1 hour Complications after initial injury and severe if it persists for more than 24 hours. Blount PJ, Bockenek WL: Heterotopic ossification, in Frontera W, Silver J (eds): Essentials of Physical Medi- Outcome Measures cine. Philadelphia, PA, Hanley and Belfus, 2002, pp 569- 574. Although there are a variety of assessment tools used in patients with brain injury, many do not have outcome A comprehensive description of HO including definition, predictive value. Among the tools used to predict out- diagnosis, and treatment is presented in this chapter. come are the Glasgow Outcome Scale, Disability Rating Scale, Functional Independence Measures, Functional Brashear A, Gordon MF, Elovic E, et al: Intramuscular Assessment Measures, and Galveston Orientation As- injection of botulinum toxin for the treatment of wrist sessment Test. and finger spasticity after a stroke. N Engl J Med 2002; 347:395-400. Several general characteristics can predict a good outcome in the brain-injured patient: limited trauma, This article discusses a randomized, blinded, and con- posttraumatic amnesia for less than 4 weeks, loss of con- trolled study that demonstrates the effectiveness of botulinum sciousness for less than 2 weeks, Glasgow Coma Scale toxin to reduce spasticity and improve ROM. score greater than 5, age younger than 60 years, strong support system, more highly educated, and premorbid Farmer SE, James M: Contractures in orthopedic and higher intelligence. A poorer outcome is predicted with neurological conditions: A review of causes and treat- recurrent injury, a mass lesion, anoxia, elevated intracra- ment. Disabil Rehabil 2001;23:549-558. nial pressure, hypotension, history of alcohol or drug use, premorbid disability, violent etiology, poor work This article reviews the scientific literature from 1966 to history, and premorbid psychiatric history. 2000 on the development and treatment of contractures in neurologic and orthopaedic conditions. Information is pre- sented on predisposing factors, muscle physiology, and the ef- fectiveness of various treatment modalities for contractures. Rehabilitative Intervention Gardner MJ, Ong BC, Liporace F, Koval KJ: Orthopedic issues after cerebrovascular accident. Am J Orthop Effective rehabilitation of the multiple impairments 2002;31:559-568. arising from stroke and brain injury requires a team ap- proach. Traditional team members include a physician, A review of the most common orthopaedic problems and nurse, psychologist, and physical, occupational, speech, deformities experienced after stroke is presented. Muscle and recreational therapists. Experienced case manage- spasticity, contractures, and HO are discussed along with ment is crucial for overall coordination, communication, methods of prevention and surgical intervention. and successful discharge. Any restrictions such as weight bearing or ROM must be identified before beginning Melamed E, Robinson D, Halperin N, Wallach N, Keren rehabilitation. Conventional approaches include ROM O, Groswasser Z: Brain injury-related heterotopic bone exercises, mobilization activities, and teaching compen- formation: Treatment strategy and results. Am J Phys satory skills. Newer promising treatments of stroke and Med Rehabil 2002;81:670-674. brain injury are focused on central nervous system re- covery using periods of intensive active motor training. In this study, the results of 12 excisions of HO in 9 patients Theoretical explanations for success of these newer were assessed. Functional improvement was noted in all pa- tients 1 year after intervention. There was no evidence of re- 642 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 53 Traumatic Brain Injury and Stroke currence. Recommendations were made regarding indications recovery in both acute and chronic hemiparesis using more in- for excision of HO. tense periods of active use of paretic limbs is explored. Poten- tial efficacy with other impairments such as dystonia, aphasia, Assessment and phantom pain are addressed. Burke DT: Traumatic brain injury, in Frontera W, Silver Yu D, Chae J: Neuromuscular stimulation for treating J (eds): Essentials of Physical Medicine, Philadelphia, shoulder dysfunction in hemiplegia. Crit Rev Phys Med PA, Hanley and Belfus, 2002, pp 806-812. Rehabil 2002;14:1-23. This chapter presents an overview of a number of func- A review of several randomized controlled trials of neuro- tional assessment tools used for patients with posttraumatic muscular stimulation to treat shoulder subluxation and pain in brain injury. hemiplegic patients is presented. Potential causes of shoulder pain are reviewed. Rehabilitative Intervention Classic Bibliography Chae J: Neuromuscular electrical stimulation for motor relearning in hemiparesis. Phys Med Rehabil Clin N Am Bonyke C, Boake C: Principles of brain injury rehabili- 2003;14:S93-S109. tation, in Braddom R, Buschbacher R, Dumitru D, et al (eds): Physical Medicine and Rehabilitation. Philadel- This article examines the types of neuromuscular electrical phia, PA, WB Saunders, 1996, pp 1027-1052. stimulation technologies being used and their clinical useful- ness in aiding upper limb functional recovery after hemipare- sis. Hesse S, Werner C, Frankenberg S, Bardeleben A: Garland DE: A clinical perspective on common forms Treadmill training with partial body weight support af- of acquired heterotopic ossification. Clin Orthop 1991; ter stroke. Phys Med Rehabil Clin N Am 2003;14:S111- 263:13-29. S123. Garland D, Keenan MA: Orthopedic strategies in the This article explores treadmill training with body-weight management of the adult head injured patient. Phys support as a means to enhance gait recovery after stroke. Ther 1983;63:2004-2009. Technical aspects of using a treadmill gait-trainer are covered. Garland DE, Rhoades ME: Orthopedic management of Snels IA, Dekker JH, van der Lee JH, Lankhorst GJ, brain-injured adults: Part II. Clin Orthop 1978;131:111- Beckerman H, Bouter LM: Treating patients with hemi- 122. plegic shoulder pain. Am J Phys Med Rehabil 2002;81: 150-160. Ippolito E, Formisano R, Farsetti P, Caterini R, Penta F: Excision for the treatment of periarticular ossification A literature review of 14 studies is presented, exploring of the knee in patients who have a traumatic brain in- the causes and treatment of hemiplegic patients with shoulder jury. J Bone Joint Surg Am 1999;81:783-789. pain. Langhorne P, Stott DJ, Robertson L, et al: Medical com- Taub E, Uswatte G, Morris DM: Improved motor recov- plications after stroke: A multicenter study. Stroke 2000; ery after stroke and massive cortical reorganization fol- 31:1223-1229. lowing Constraint-Induced Movement therapy. Phys Med Rehabil Clin N Am 2003;14(suppl 1):S77-S91. Woo BH, Nesathural S (eds): The Rehabilitation of Peo- ple With Traumatic Brain Injury. Boston, MA, Blackwell This article reviews newer theories on brain plasticity and Science Inc, 2000, pp 13-17, 35-43, 95-99. the effects of learned nonuse. The potential for greater motor American Academy of Orthopaedic Surgeons 643



Chapter 54 Limb Amputation and Prosthetic Rehabilitation Michael C. Munin, MD Gary F. Galang, MD Incidence and Etiology tients who underwent reconstruction were not signifi- cantly different from those who underwent amputation. The most recent (1993) National Health and Human However, reconstruction was associated with a higher Services data show that there are about 1.5 million am- risk of complications, additional surgeries, and rehospi- putees in the United States, with 50,000 new amputa- talization. tions occurring each year. About 5% of amputations are tumor related, 15% result from trauma, and the remain- Surgical Technique and Functional Outcomes ing approximately 80% are vascular in etiology, with diabetes-related ischemic vascular disease as the major Bone cause. In the United States there was a 27% increase in the overall rate of dysvascular amputations from 1988 to In general, ambulation and prosthetic control are opti- 1996, with a large part of the increase occurring in geri- mized with the preservation of the knee joint and main- atric and minority populations. Traumatic and cancer- tenance of a longer residual bone length, which provides related amputations decreased by one half within the better pressure distribution that minimizes skin break- same period. The average age for patients with amputa- down with prosthetic wear. A longer residual bone tion resulting from vascular etiologies is between age 51 length also provides a longer torque arm, improving to 69 years, whereas the average patient age for trauma- control and decreasing the metabolic demands of pros- related amputations is 21 to 30 years. The overall male thetic ambulation. In geriatric dysvascular amputees, to female ratio is approximately 2:1. 90% of transtibial amputees will successfully use a pros- thesis compared with 25% or fewer of transfemoral am- Most adult limb amputations occur in the lower ex- putees. Postoperative surgical wound healing is rela- tremity (80%); partial foot amputations comprise 50% tively higher at the transfemoral level (70% to 98%) and transtibial and transfemoral amputations about compared with the transtibial level (30% to 90%) in 25% each. Upper extremity amputations account for dysvascular patients. This finding suggests that the trans- the remaining 20% of all amputations, with most result- femoral level may be more suitable for geriatric patients ing from work-related injuries involving the dominant with fewer activity demands. Younger patients can have arm in healthy younger patients. The most common up- excellent outcomes at the transfemoral level with appro- per limb amputations are at the transradial level (57%), priate prosthetic prescriptions and training. followed by transhumeral amputations (23%). At the transtibial level, the ideal surgical margin is at Congenital abnormalities are the most common the musculocutaneous junction of the gastrocnemius cause of limb deficiencies for patients younger than age muscle. Longer bone lengths provide less soft-tissue 10 years. Causes of congenital amputation include intra- padding and poorer blood supply for the myocutaneous partum exposure to drugs and radiation (10%) and ge- flap. Furthermore, because of the height requirements netic deficits (20%); the etiology of the remaining 70% of the foot and ankle assembly, longer bone lengths may is unknown. Congenital upper limb absence is usually preclude the addition of important components such as seen at the level of the transverse upper third of the left a vertical shock pylon and rotator unit. The recom- radius. mended transtibial residual limb length is 12.5 cm to 17.5 cm or approximately 2.5 cm of bone length per 30 Limb salvage or reconstruction has recently become cm of body height. A residual limb length that measures an increasingly viable alternative to amputation for pa- 33% to 50% of the intact tibial length from the medial tients with a traumatic or oncologic etiology. A recent tibial plateau to the medial malleolus is also recom- multicenter study comparing surgical reconstruction mended. In transfemoral amputations, a 5-cm stump with limb amputation after major trauma (type IIIB, length measured from the greater trochanter is fitted as IIIC tibial fractures) reported that the outcomes for pa- American Academy of Orthopaedic Surgeons 645

Limb Amputation and Prosthetic Rehabilitation Orthopaedic Knowledge Update 8 a hip disarticulation. A transfemoral residual bone ever, soft-tissue coverage is less than attained in poste- length between 50% to 75% of the intact femur mea- rior flap closures. sured from the greater trochanter to the lateral femoral condyle is considered optimal. Nerve Beveling the cut cortical bone at the site of amputa- Careful attention should be given to the treatment of tion is recommended regardless of surgical level. Ideally, the transected nerves in an attempt to prevent symp- a 45° angle may prevent pressure on the anterior skin tomatic neuroma formation to minimize future pain. flap. In transtibial amputations, sectioning the fibula 1.2 Careful traction followed by transection allows the cm shorter than the tibia is also recommended. Com- nerve to recoil within the soft tissues of the residual plete removal of the fibula and adjacent muscle bulk limb. Silicone capping, grafting with an epidural nerve was previously performed for short residual limbs; how- sheath, or a venous graft may prevent disorganized ever, this practice is not currently recommended be- nerve regeneration and sprouting. However, most tech- cause retention of the fibular head is important for an- niques currently in use do not eliminate neuroma for- choring the total contact socket within the residual limb. mation and more studies are required to determine the best long-term outcomes. Soft Tissue Preoperative Consultation Adequate padding and coverage to the distal bone is achieved by muscle stabilization techniques and skin Optimal care begins before surgery. When amputation is flaps with the goal of attaining a muscular, cylindrical, considered, patient consultation with a physiatrist, phys- residual limb to provide ideal prosthetic fitting. Muscle ical therapist, prosthetist, and a functioning amputee is stabilization through myoplasty and tension myodesis necessary to facilitate a smoother transition into pros- not only provides more soft-tissue coverage but also thetic training. The physiatrist coordinates all the efforts acts as a replacement insertion that facilitates muscle of the rehabilitative team, provides input on the recom- contraction and movement. In tension myodesis, mended surgical level of amputation and limb length, in- transected muscle groups are sutured to bone under forms the patient about the anticipated postoperative physiologic tension. In myoplasty, the muscle is sutured rehabilitation protocol and outcomes, and explains po- into soft-tissue fascia or opposing muscle groups. In tential problems. The physical therapist can initiate pre- younger more active patients who need firmer stabiliza- prosthetic training before surgery by educating the pa- tion, a myodesis is preferred. In transfemoral amputa- tient on conditioning and range-of-motion exercises for tions, it has been reported that the absence of adductor the affected extremity. The prosthetist can provide valu- magnus myodesis results in a loss of 70% of hip adduc- able input on the latest advances in rehabilitation tech- tion power. Furthermore, myodesis prevents the antero- nology, concentrating on limitations so as not to create lateral drift of the distal femur caused by muscular im- false expectations. A functioning amputee provides the balance from the hip abductors that are unaffected by patient with psychological reassurance that a health pro- the transfemoral amputation. Both procedures are rela- fessional may not be able to convey. tively contraindicated in ischemic limbs because they may further compromise the already marginal blood Immediate Postoperative Treatment supply. Wound Protection and Coverage The type of skin and soft-tissue flaps are determined by the vascular supply of the distal limb. In transtibial Wound protection and edema control can be achieved amputations, blood supply in the posterior and medial simultaneously with a postoperative compressive dress- aspects of the leg is more abundant than in the antero- ing such as an elastic stockinette (stump shrinkers) or lateral region. In ischemic limbs, a long posterior myo- elastic bandages. Elastic bandages require proper appli- cutaneous flap and a short or even absent anterior flap cation to avoid proximal constriction from a tourniquet is recommended. A posterior flap that measures 1 cm effect. An elastic stockinette tends to be easier to apply more than the diameter of the leg at the level of the and provides reasonable control of edema. Some pa- bone division is recommended. To preserve all intact tients may experience pain as the stockinette is pulled vascular connections between muscle and skin, dissec- across the incision line and function better with elastic tion along tissue planes is avoided and myocutaneous bandages. A nonremovable plaster cast can be placed flaps are used. Occasionally, to provide more coverage, a immediately after the amputation for protection; how- vascular graft can be taken from the other leg. ever, this technique prevents wound inspection and can result in pistoning and skin breakdown when residual The fish mouth or guillotine transtibial amputation limb edema subsides. A removable rigid dressing made is indicated for patients with ischemic limbs or those of thermoplastic provides wound coverage and edema who require delayed primary wound closure. The proce- control and allows wound inspection and dressing dure uses equal length anterior and posterior flaps; how- changes. It can be fabricated to resemble a socket to im- 646 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 54 Limb Amputation and Prosthetic Rehabilitation prove residual limb shape or it can be formed into a bi- include α-2 agonists (clonidine), N-methyl D-aspartate valve or clamshell design. This approach can be used for receptor antagonists (amantidine, dextromethorphan), patients who need protection from falling and acciden- anti-inflammatory agents, magnesium sulfate, or cannab- tal contact while waiting for the residual limb to mature. inoids. Range of Motion Preoperative analgesia with intrathecal anesthetics or opioids has been beneficial in patients with long- A range-of-motion and contracture prevention protocol standing preamputation pain. This regimen is initiated is integral in the early postoperative course. Lying preoperatively and continued for up to 3 days after am- prone, bedside range-of-motion exercises, and early mo- putation before converting to an oral regimen. Neuroma bilization can prevent knee flexion and hip abduction/ excision with the combination of funiculectomy, epineu- external rotation contractures that are seen in lower ex- ral sleeve suture ligation, or silicone capping is being tremity amputees. It has been shown that early performed but long-term outcome studies are not yet contracture was independently associated with the in- available. Local neurolysis with phenol/glycerin has pro- ability to complete an inpatient prosthetic rehabilitation vided relief in patients for whom neuroma excision has program soon after amputation surgery. been unsuccessful. Ultrasound for identification and guidance during neurolysis also has been used with Postamputation Pain moderate success. Cortical, thalamic, and dorsal column stimulators implanted to stimulate neuroinhibitory path- The treatment of pain has important functional and ways can provide neuromodulation of neuropathic pain prognostic implications. Pain is present in up to 70% of but not nociceptive pain. Intrathecal pumps that infuse amputees immediately after surgery and in 50% after 5 clonidine, anesthetics, or opioids have been implanted in years. Along with ambulation distance, pain is the most patients with intractable pain. important amputation-specific determinant of health- related quality of life. Pain is experienced as hyperalge- Mechanical stimulation by gentle residual limb tap- sia (a stronger or earlier withdrawal response to noxious ping and the application of transcutaneous electrical or stimuli) or allodynia (the sensation of pain from non- vibratory stimulation have been the usual physical mo- noxious stimuli). Phantom limb pain is defined as the dalities for treating postamputation pain. The use of nociceptive sensation of the amputated limb. transcutaneous nerve stimulation has had moderate suc- cess and can be applied directly to the site of pain, on Generally, postamputation pain can be attributed to the contralateral limb, or even auricularly. Prosthetic local and biomechanical factors affecting the residual wear and early mobilization promotes afferent signals limb or to the changes to the peripheral and central ner- that increase cortical reorganization and may relieve vous systems caused by the amputation. Local factors neuropathic pain in many patients. include ischemia, infection, wound dehiscence, and skel- etal abnormalities (such as ectopic bone formation, ex- Prosthetic Training cess fibular length, and inadequate tibial beveling). Neu- ropathic pain is often manifested as residual limb pain Prior research has supported both immediate prosthetic secondary to a neuroma, pain in the missing limb (phan- training and delayed prosthetic fitting. Vascular transtib- tom limb pain), or sympathetically driven pain. ial amputees treated with a rigid intrasurgical plaster cast followed by early postoperative prosthetic limb fit- The treatment of neuropathic pain after amputation ting have been compared with those referred to an am- does not produce perfect results and often requires a putee clinic for fitting several weeks after hospital dis- multidisciplinary approach. Pain management protocols charge. A significant decrease in the number of total include pharmacologic agents, mechanical, surgical, and hospitalization days was noted in the group who had physical modalities (exercise), psychological counseling, early prosthetic limb fitting, implying increased cost ef- and behavioral approaches including imagery tech- fectiveness with this approach. In another study, out- niques. comes for patients with immediate prosthetic transtibial fitting were examined and no significant variation was The antiepileptics, tricyclic antidepressants, and opio- found in terms of local necrosis or infection. In a more ids are the most commonly used oral medications for recent study, a 68% success rate in early prosthetic fit- postamputation neuropathic pain. Gabapentin, an antie- ting was reported despite strict inclusion criteria that pileptic agent with both gamma-aminobutyric acid and only admitted patients who it was believed would bene- glutamate antagonist properties, is shown to decrease fit from this approach. Based on this data, a postopera- neuropathic pain and is relatively well tolerated. De- tive delay of about 3 weeks before beginning prosthetic sipramine, a tricyclic antidepressant, could also be con- rehabilitation was recommended, although some pa- sidered a first-line drug. The role of opioids in the treat- tients will require a preprosthetic rehabilitation pro- ment of neuropathic pain is controversial but remains gram. clearly indicated in acute postamputation pain. Other medications that are used in neuropathic pain disorders American Academy of Orthopaedic Surgeons 647

Limb Amputation and Prosthetic Rehabilitation Orthopaedic Knowledge Update 8 Early functional training includes donning and main- are done to prevent the equinus deformity. For this level tenance of the prosthetic device, residual limb desensiti- of amputation, a special shoe or a slipper-like prosthesis zation, strengthening, gradual and monitored increased or a combination of both is provided. A ground-reacting prosthetic wear, and gait retraining. Strengthening of ankle-foot orthosis with anterior and posterior shells is the quadriceps, glutei, and hamstring muscles must be prescribed in a muscularly imbalanced and pressure- done as these muscle groups compensate for the loss of sensitive foot to provide maximal control. the ankle and/or knee. The duration of prosthetic wear should be gradual, beginning with 30-minute intervals The Boyd amputation excises all the tarsal bones ex- two times a day and increasing to several hours at a cept the calcaneus. Because of resultant residual limb time with frequent skin checks. Gait training is started problems, it is not a popular procedure and is used pri- with parallel bars to facilitate weight acceptance on the marily for the pediatric congenital amputee. The Syme’s residual limb. Weight bearing is gradually increased on amputation is an ankle disarticulation with a heel flap the prosthetic limb. Gait retraining is initiated using a attached securely to the distal tibia to provide weight step to gait pattern leading to a step through gait pat- bearing on the residual limb. Cosmetic concerns may tern. It is important to achieve a smooth gait pattern limit acceptance of this procedure because the distal re- with equal step-lengths to avoid gait deviations that in- sidual limb has a bulbous shape. The Syme’s prosthesis crease metabolic energy expenditure. The early estab- extends to the proximal tibia but has a removable me- lishment of an energy-efficient walking pattern has con- dial wall to allow the bulbous distal limb to enter the siderable long-term implications that affect function and socket. The foot component is similar to that used in a independence. transtibial amputation but with a lower profile to ac- commodate the residual limb. Prosthetic Components and Prescription Transtibial Components The technology involved in the development of pros- Foot and Ankle Assembly thetic components has evolved significantly in the past The solid ankle cushioned heel exemplifies the earlier decade. The incorporation of titanium, carbon fiber, and foot assemblies. It consists mainly of a semirigid wooden other metal alloys has increased the rigidity and tensile keel surrounded by a resilient material concentrated at strength of the components without adding weight. The the heel. At heel strike, energy is absorbed with the use of silicone liners and sockets composed of flexible compression of the heel assembly and a plantar flexion plastics along with suction suspension has generally in- moment is simulated. A stable base of support is pro- creased comfort and decreased skin breakdown. Poly- vided by the keel, which hyperextends at the metatar- centric and multiaxial joints and terminal devices with sophalangeal line at heel-off. During the swing phase, pneumatic, hydraulic, and computer-driven controls the unloaded toe region reverts to its neutral position. have contributed to a smoother and more energy- The use of this design is limited to home ambulators or efficient gait pattern. The goal of prosthetic wear has those patients with limited insurance coverage. gone beyond community ambulation to educational, vo- cational, and recreational activities as well. Dynamic response feet store energy at heel strike and transmit the forces to the keel during heel-off, pro- Partial Foot Amputation viding recoil. Examples include the Seattle (Model and Instruments Works, Inc, Seattle, WA), the Carbon Copy The amputation of a single toe, except for the big toe, II (Ohio Willow Wood Co, Mt. Sterling, OH), the Quan- results in minimal loss of function. Toe spacers are in- tum (Hosmer Dorrance Corp, Campbell, CA), and the serted to fill the void and to prevent further deformities Flex (Ossur North America, Aliso Viejo, CA) foot de- (varus or valgus) in the remaining toes. The amputation signs. Because they provide a better spring for running of the first ray significantly affects push-off; therefore, a and jumping, these prosthetic foot designs are recom- long steel shank and a rocker bottom is usually pro- mended for more active individuals. vided as compensation. For transmetatarsal amputa- tions, a custom molded insole with a toe filler is recom- Articulated foot assemblies provide motion at the mended. anatomic location of the ankle, better accommodate un- even surfaces, and absorb torsional forces reducing Proximally, the Lisfranc amputation is a transmeta- torque to the limb by the socket. Designs are either sin- tarsal disarticulation whereas a Chopart amputation is a gle axis, which provide dorsiflexion and plantar flexion, disarticulation at the midtarsal joint through the talo- or multiaxis, which provide motion in the dorsiflexion- navicular and calcaneocuboid joints. Both of these pro- plantar flexion and inversion-eversion planes. The Col- cedures may result in a significant equinovarus defor- lege Park (College Park Industries, Frasier, MI), Luxon mity with anterior weight bearing through the scar line, (Otto Bock North America, Minneapolis, MN), and En- predisposing to skin breakdown over time. Early post- operative rigid dressing and Achilles tendon lengthening 648 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 54 Limb Amputation and Prosthetic Rehabilitation dolite (Endolite North America, Centerville, OH) de- don, the pretibial muscles, the gastrocnemius/ signs are common examples of multiaxis foot assem- gastrocnemius-soleus complex muscles, the popliteal blies. fossa, the lateral flat aspect of the fibula, and the medial tibial flare. The pressure-sensitive areas include the tib- Heel height adjustability is a feature developed to ial crest, tubercles, condyles, the fibular head, the distal address cosmetic issues in patients who use footwear of tibia and fibula, and the hamstring tendons. varying heel heights. This option is often incorporated into the foot assembly. The Century 22 (Otto Bock The patellar tendon-bearing socket is the most fre- North America) foot offers manual adjustment of vary- quently used. Although it is designed to put substantial ing heel heights from 35 to 50 mm. weight on the patellar tendon, its intimate contact with the entire residual limb provides even distribution of Occasionally, a torque absorber is placed between pressure with minimal distal end bearing. The trim line the shank and the foot assembly to absorb torsional extends anteriorly to the lower patella level, mediolater- forces as the prosthesis twists around the residual limb ally to the femoral condyles, and posteriorly below the during ambulation. This modification is recommended level of the hamstring tendon insertions. for patients with skin conditions or for those who partic- ipate in sport activities or vocations that require signifi- For shorter residual limbs and those with mediolat- cant foot rotation. eral instability, a patellar tendon supracondylar socket is more appropriately prescribed. A supracondylar socket Pylon extends above the medial and lateral femoral condyles The pylon is the interphase between the foot assembly using the bony ridges to suspend the prosthesis. It pro- and the socket and is classified as having an endoskele- vides better mediolateral knee support and is appro- tal or exoskeletal design. Endoskeletal pylons consist of priate for shorter residual limbs. A supracondylar/ a rigid and unyielding central support surrounded by a suprapatellar suspension uses the same design but polyurethane, soft cosmetic cover to allow for a more extends the anterior trim line to envelop the patella for natural appearance. Substitution of isolated components added support. This particular feature also helps coun- (socket, shank, and foot) is also possible without dis- teract genu recurvatum forces. carding the entire prosthesis. This situation is ideal in early prosthetic rehabilitation when a temporary or in- Suspension Systems termediate prosthesis is provided or in the pediatric Mechanical suspension devices are external devices that population to allow for limb growth. Recent improve- are attached to anchor on bony prominences to provide ments in material construction using titanium and car- stabilization. They are indicated early after amputation bon fiber have significantly increased the weight limit when there is significant volume fluctuation along the for these pylons to as much as 350 lb. residual limb secondary to edema. They also are useful in older amputees with poor hand dexterity and poor Exoskeletal or crustacean shanks are solid blocks of residual limb bulk and tone. Examples include: (1) A su- hard plastic or wood molded to resemble the intact limb prapatellar suspension strap that is fastened to the me- and hollowed in the middle to reduce weight. The exte- dial and lateral socket walls passing over the superior rior surfaces are laminated to provide waterproofing. border of the patella. This device offers some resistance Although more rigid and stronger than the endoskeletal to knee hyperextension forces and is relatively easy to pylon designs, they are heavier and revisions often en- put on and take off; however, it is prone to mild piston- tail discarding the entire prosthesis. Their use is limited ing and is not indicated for short, painful residual limbs to relatively obese patients or people such as farmers or with mediolateral instability. (2) A thigh corset secured outdoorsmen who are constantly exposed to environ- to the socket by sidebars and a knee joint assembly is ments that could corrode the more intricate components useful to take weight off of the residual limb and to pro- of the endoskeletal pylon. vide better rotational stability. (3) Anteriorly, a fork strap can be attached to a waist or pelvic belt to add sta- Recent designs have also incorporated the pylon bility in the anteroposterior plane and to help suspend with the foot assembly. The Re-Flex Vertical Shock py- the prosthesis, especially in knee flexion. It is indicated lon (Ossur North America) integrates a foot with a ver- for shorter residual limbs and for obese patients who tical shock-absorbing pylon that returns energy both in cannot use a suprapatellar strap. (4) Over-the-knee the vertical and sagittal planes. sleeves are fabricated from a flexible material such as neoprene, which extends from the proximal end of the Socket prosthesis to the distal thigh. The socket acts as an interphase between the residual limb and the prosthesis and applies weight-supporting Atmospheric or suction types of suspension are gen- forces to the residual limb. In socket fabrication, erally preferred over mechanical types to minimize pis- pressure-tolerant areas are built up for more contact toning and shearing forces. However, they require ade- and pressure-sensitive areas are relieved to minimize quate hand and visual function to apply. Furthermore, contact. Pressure-tolerant areas include the patellar ten- American Academy of Orthopaedic Surgeons 649

Limb Amputation and Prosthetic Rehabilitation Orthopaedic Knowledge Update 8 suction suspensions may provide undue stress to a heal- ity, or lack of rotational control. Less restrictive suspen- ing surgical wound, thus promoting delayed wound sion would include a Silesian belt or total elastic suspen- healing or wound dehiscence; they are typically with- sion belt, which is composed of neoprene with held early in the postoperative period until volume fluc- reinforced elastic bands running at oblique angles poste- tuations have stabilized. One example is a prefabricated, riorly and anteriorly around the waist. A silicone liner closed-end silicone elastomer liner that is flexible with a distal pin and shuttle lock similar to that found in enough to adapt to the irregular surfaces in the residual transtibial devices can be used. This component adds limb and to promote an airtight environment to achieve length and in combination with the knee unit may cause suspension. This device is rolled proximally up and over an uneven knee axis (prosthetic thigh longer than intact the knee and is secured to the socket by means of a thigh), leading to cosmetic and biomechanical deficits. A shuttle lock mechanism, which consists of a pin at the suction suspension is ideal for patients with mature re- distal end of the liner and a locking mechanism located sidual limbs. Surface tension, negative pressure, and at the bottom of the socket. Early in the postamputation muscle contractions suspend the prosthesis from the period when the residual limb volume fluctuates signifi- limb without the need for a waist belt. Suction is gener- cantly, the pin and shuttle lock mechanism can be de- ated by placing the residual limb into the socket with a ferred in lieu of a supracondylar strap. The Iceross (Os- nylon pull sock or using a lubricating lotion, then expel- sur North America) and Alpha (Ohio Willow Wood) ling air with a one-way valve. liners are examples of silicone liners. Another example is the Vacuum Assisted Socket System (Otto Bock Knee Assembly North America), which consists of a silicone liner, a sus- Knee assemblies consist of a joint or bolt that allows pension sleeve, and an air evacuation pump that creates flexion and extension, an extension stop that limits hy- an elevated vacuum of 15 mm Hg between the liner and perextension, and a friction device that provides the socket wall. This design controls volume fluctuation smoother motion along the assembly. General classifica- and promotes a more secure and intimate fit between tions are based on axis and control, either on swing or the residual limb and socket. stance phase. Transfemoral Components A single axis knee assembly acts as a hinged joint and is preferred for its simplicity, reliability, minimal Socket Design maintenance, and cost. It is also ideal for children be- The two main transfemoral socket designs are termed cause growth entails frequent changes in prosthetic quadrilateral and ischial containment. The quadrilateral components. A polycentric or multiaxis knee is more socket has its posterior border under the ischial tuberos- physiologic and uses multiple bar linkages along the ity and buttocks for weight bearing, with the anterior bolt to allow a shifting mechanical axis during flexion border providing a posteriorly directed force to control and extension. This feature provides more stability while the femur. Therefore, it is narrow anteroposteriorly and allowing for improved performance at higher walking wide mediolaterally. An ischial containment socket speeds. should contain the ischial tuberosity and apply counter pressure from the lateral wall of the socket. It is narrow Control is provided either at the stance or swing mediolaterally and wider anteroposteriorly. Quadrilat- phase. Stance phase control is provided for patients with eral socket designs are useful for obese patients, knee instability who cannot control knee flexion. A whereas more active patients may benefit from the is- manual locking knee is used to maximize stability; how- chial containment design that maintains the femur in ever, this eliminates knee motion throughout the gait adduction, allowing the gluteal musculature to generate cycle and is recommended for limited household ambu- maximal tension at an ideal resting length. Material con- lators. Stance phase weight-activated control is used for struction can be either rigid (wood, plastic laminates), those with slightly better overall knee stability who flexible, or a combination of both (Scandinavian or need support during upright activities. Icelandic-Swedish-New York sockets). The outer hard socket can be windowed posteriorly and anteriorly to al- The presence and type of swing phase control is de- low improved comfort with sitting. In this situation, a termined by the patient’s ability to vary cadence. A con- flexible inner liner is used in contact with the skin. stant friction device is used for elderly patients who walk at a constant speed. This unit has a split bushing Suspension Device and clamp around the knee bolt, which provides con- The transfemoral suspension devices can either be me- stant friction throughout the swing phase. The amount chanical or atmospheric. A pelvic belt and hip joint of- of friction is controlled by a friction adjusting screw that fers maximal stabilization and is best suited to those tightens or loosens the bushing. For active patients who with short residual limbs, significant mediolateral stabil- want to vary walking speeds and run, hydraulic or pneu- matic swing phase control devices are used. Hydraulic and pneumatic mechanisms adjust resistance to changes 650 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 54 Limb Amputation and Prosthetic Rehabilitation Table 1 | The Centers for Medicare and Medicaid Services don to the cruciate ligaments. This procedure is done on Functional Levels of Ambulation patients with traumatic injuries and very short residual tibiae above the tubercle, or on elderly dysvascular pa- Level Amputee and Prosthetic Characteristics tients without prosthetic potential who need to bear K0 Patient cannot transfer independently weight on the residual limb for transfers. The knee disar- ticulation prosthesis consists of a modified quadrilateral Prosthesis will not enhance quality of life or mobility transfemoral socket with some ischial weight bearing K1 Patient has the ability or potential to use a prosthesis for and a four-bar linkage polycentric knee that may result in uneven knee axes. transfers or ambulation on level surfaces with a fixed ca- dence Functional Levels Patient has limited or unlimited household ambulation A solid ankle cushioned heel foot or a single axis foot; a man- The Centers for Medicare and Medicaid Services have identified functional levels of ambulation with corre- ual locking, single axis or polycentric knee unit (with or sponding components deemed appropriate for each without stance phase weight-activated control); or any level of activity (Table 1). This classification system is socket or suspension design is allowed only applicable to patients with single lower extremity K2 Patient has the ability to traverse low-level environmental amputation. It is also possible for a classification to be barriers such as curbs, stairs, or uneven surfaces with a upgraded if initial expectations are exceeded. constant cadence All K1 prosthetic components are allowed with the addition of Common Gait Abnormalities in Lower Limb flexible keels or multiaxial feet, rotators, and torque absorb- Prosthetic Rehabilitation ers K3 Patient has the ability or potential for ambulation with vari- Transtibial Deviations able cadences Patient can traverse most environmental barriers Excessive knee flexion during heel strike could be May have vocational, therapeutic, or exercise activity that caused by a foot placed in dorsiflexion, an excessively demands prosthetic use beyond simple locomotion stiff heel cushion, anterior translation of the socket in All K1 and K2 prosthetic components are allowed with the relation to the pylon, or a residual limb flexion contrac- addition of hydraulic/pneumatic knees and dynamic or ture. Insufficient knee flexion can be caused by plantar shock absorbing pylons flexion of the foot, an excessively soft heel cushion, pos- K4 Patients have the ability or potential for prosthetic use that terior displacement of the socket in relation to the py- exceeds basic ambulation lon, or weak quadriceps on the residual limb. Patients exhibit high impact and energy levels typical of the growing child, active adult, or athlete Lateral thrust occurs when the pylon is placed medi- All existing prosthetic components are allowed in this func- ally, creating a varus moment. The patient usually re- tional level ports concomitant pain and pressure on the medial fem- oral condyle and lateral distal tibia. Medial thrust is an in the rate of motion and this improves knee control analogous problem with the pylon placed laterally, caus- and provides a smoother gait pattern. ing a valgus moment. Patients often report pain on the lateral femoral condyle and medial distal tibia. These The C-Leg deviations are corrected by repositioning the pylon to In 1999, a microprocessor knee unit called the C-Leg the socket in the coronal plane. (Otto Bock North America) was introduced in the United States. This knee unit uses force sensors in the Transfemoral Deviations pylon that detect knee angles and loading forces at the foot and ankle that are then sampled by onboard micro- Lateral trunk bending is a trunk lean to the prosthetic processors 50 times per second. The C-Leg was reported side during the stance phase. It occurs because of an ab- to allow patients to have a significant reduction in oxy- ducted socket, a hip abduction contracture, insufficient gen consumption during slower speed ambulation and lateral support of the prosthetic socket, a short prosthe- to achieve a wider range of cadences compared with a sis, or weak ipsilateral hip abductors. conventionally controlled hydraulic single axis knee. However, randomized trials comparing this technology Circumduction is a curvilinear motion of the pros- to multiaxis hydraulic knee designs are needed to deter- thesis during the swing phase and is caused by a func- mine optimal patient selection. tionally longer prosthetic limb length, which creates dif- ficulty in clearance. Common causes include an ill-fitting Knee Disarticulation socket that pistons or does not fully accommodate the residual limb, a manual locking knee, a device that Knee disarticulations involve the removal of the tibia causes excessive knee friction, or a foot in plantar flex- and fibula at the knee with suturing of the patellar ten- ion. American Academy of Orthopaedic Surgeons 651

Limb Amputation and Prosthetic Rehabilitation Orthopaedic Knowledge Update 8 Table 2 | Metabolic Cost of Ambulation Per Level and Na- more, 95% of the survivors wore prostheses and averaged ture of Amputation 80 hours of use per week. An earlier study involving younger amputees showed a 79% job reintegration rate. Amputation Level Metabolic Cost Age at the time of amputation, comfort of the prosthesis, Syme’s Increased 15% education level, and lowering of the physical demands in Traumatic transtibial Increased 25% the workplace were positive predictors for return to work. Vascular transtibial Increased 40% Pain did not appear to be associated with return to work Traumatic transfemoral Increased 68% but was directly associated with work-related satisfaction. Vascular transfemoral Increased 100% Upper Limb Amputation and Prosthetic (Data from Czerniecki JM: Rehabilitation in limb deficiency: Gait and motion analysis. Arch Components Phys Med Rehabil 1996;77:S3-S8.) Levels of Amputation Vaulting is described as excessive plantar flexion of the intact foot during the prosthetic swing phase and oc- The transradial amputation is the most common and curs because of a functionally longer prosthetic limb preferred upper extremity amputation. The residual length for reasons similar to those that create a circum- limb length can be classified as either long (55% to duction moment. 90%), medium (35% to 54%), or short (0 to 34%) based on the length of the intact forearm measured Medial or lateral heel whip is often caused by rota- from the medial epicondyle to the distal ulna or radius. tional malalignment of the knee apparatus in compari- Because of component weight and length consider- son to the tibial components. A knee unit placed in ex- ations, the long transradial residual limb provides the cessive external rotation leads to a medial whip; a knee longest lever arm most suitable for a body-powered unit placed in excessive internal rotation results in a lat- prosthesis. A medium length transradial residual length eral whip. provides enough clearance for externally powered pros- thetic components. The short transradial limb is difficult Long-Term Prosthetic Rehabilitation Issues to suspend and may promote deficits in elbow strength and range of motion. Elbow disarticulations may pose Metabolic Requirements cosmetic concerns because of limited options in exter- nally-powered elbow units available for this amputation The metabolic requirements of ambulation increase level. proportionally with decreased length of the amputated limb, the number of amputated joints, and the number Transhumeral amputations are also classified by re- of amputated limbs. Furthermore, vascular amputees sidual limb length (short, medium, and long), but the have higher metabolic requirements than their trau- prosthetic options and rehabilitative interventions are matic counterparts. Amputees, however, offset the in- similar at each level. Shoulder disarticulations and fore- creased metabolic demands by choosing a slower self- quarter amputations are reserved for tumor excision selected walking pace. Patients should not be denied surgeries because of the difficulty in providing a pros- prosthetic fitting and training on the basis of cardiopul- thesis with adequate suspension. monary limitations unless these limitations are pro- found. The metabolic cost of ambulation based on the Prosthetic Control level and nature of amputation is shown in Table 2. Upper extremity prosthetic control is usually either Functional Outcomes and Work Reintegration body powered, externally powered, or a combination of both. Body-powered control is provided by the intact The long-term survival rate for patients after dysvascu- movements of the residual limb that connects to cables lar lower extremity amputation is 50% to 70% at 2 to flex and extend the elbow or open and close the ter- years, and 30% to 40% at 5 years with a postoperative minal device. The movements include scapular abduc- mortality rate of 10% to 30%. Heart disease is the most tion; chest expansion; shoulder depression, flexion and common cause of death (51%), followed by carcinoma- abduction; and elbow flexion. Myoelectric controls use tosis (14%) and cerebrovascular accidents (6%). The the electrical activity generated by muscle contractions risk of contralateral limb amputation reaches 15% to to control the flow of energy from a battery to a motor 20% in 2 years after the initial amputation and the controlling the terminal device or elbow unit. Compara- reamputation rate of the ipsilateral limb in a transtibial tive studies between myoelectric and body-powered dysvascular patient ranges from 4% to 30%. hands showed no significant difference in terms of per- formance that could limit application of this technology Traumatic amputees show more favorable outcomes. to specialized situations. In a 2001 study, a 9% acute admission mortality rate with only a 3.5% 10-year mortality rate was found. Further- 652 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 54 Limb Amputation and Prosthetic Rehabilitation Prosthetic Components Dillingham TR, Pezzin LE, MacKenzie EJ: Limb ampu- tation and limb deficiency: Epidemiology and recent The terminal device attempts to approximate the complex trends in the United States. South Med J 2002;95: functions of the hand and is available in different designs 875-883. based on the user’s preference. The devices can either be hooks that provide lateral pinch or hands that provide a This study provides a comprehensive perspective on the three-jaw chuck pinch. They can be passive or purely cos- epidemiology of limb amputations in the United States using metic, body powered, or externally powered. Body- linear regression techniques on data from 1988 to 1996. Dys- powered designs are either voluntary opening or volun- vascular amputations have increased to 27%, accounting for tary closing; the selection depends on the patient’s 82% of all limb loss. Rates of trauma and cancer-related am- anticipated use (for example, an amputee who plans to putations have declined by one half and the incidence of con- work in a factory would benefit from a voluntary closing genital deficiencies has remained stable. terminal device, which would not get caught in the assem- bly line). Terminal devices cannot provide the sensory Immediate Postoperative Treatment feedback and dexterity of an intact hand. Myoelectric- powered hands allow for a proportional grasp. Slip con- Bone M, Critchley P, Buggy DJ: Gabapentin in postam- trol systems have microprocessors that maintain constant putation phantom limb pain: A randomized, double- pressure on the object to prevent slippage. blind, placebo-controlled, cross-over study. Reg Anesth Pain Med 2002;27:481-486. Wrist designs can be manually or externally con- trolled, and most provide passive supination and prona- This study used a randomized, double blind, placebo- tion with a friction lock to control rotation when lifting controlled crossover methodology. Subjects with severe phan- heavier objects. Quick disconnect wrists allow for easy tom limb pain were enrolled in a 6-week course of gabapentin interchange of terminal devices. Elbow mechanisms are therapy titrated by increments of 300 mg to a maximum of either internal or external and can also be passive, body 2,400 mg per day versus the control group. Significant im- powered, or externally powered. Body-powered designs provement in terms of pain intensity was found in patients are controlled with mechanical cables through move- treated with gabapentin as compared with those given the pla- ments of the residual limb or can be manually locked by cebo. However, no differences were noticed in terms of rescue the contralateral hand, chin, or the ipsilateral shoulder. medication (codeine/paracetamol) required, sleep disturbance, Electrical elbows are operated by electrical switches or or function as measured by the Barthel index. myoelectric impulses. Ernberg LA, Adler RS, Lane J: Ultrasound in detection Prosthetic socket design also has progressed with the and treatment of painful stump neuroma. Skeletal development of lightweight and durable materials. Flex- Radiol 2003;32:306-309. ible thermoplastics provide better fit and comfort and are used in the internal layer, which comes in close con- The use of ultrasound has shown considerable success in tact with the residual limb. Carbon fiber has replaced the assessment of amputation stump neuromas. This study in- wood or laminated plastics in the external layer. Me- vestigates the usefulness of ultrasound guided localization for chanical suspension devices usually consist of harness steroid injection of amputation stump neuromas. systems that anchor across the shoulders. Fabric liners as well as silicone suction suspension systems are also Munin MC, Espejo-De Guzman MC, Boninger ML, available for the upper extremity prostheses. Fitzgerald SG, Penrod LE, Singh J: Predictive factors for successful early prosthetic ambulation among lower- Annotated Bibliography limb amputees. J Rehabil Res Dev 2001;38:379-384. Incidence and Etiology In an effort to predict successful outcomes with early pros- thetic rehabilitation, demographic and medical factors were Bosse M, MacKenzie EJ, Kellam JF, et al: An analysis of analyzed in a group of lower extremity amputees admitted to outcomes of reconstruction or amputation after leg an inpatient rehabilitation facility. Sixty-eight percent of the threatening injuries. N Engl J Med 2002;347:1924-1931. patients met criteria for successful ambulation at time of dis- charge. The absence of lower extremity contractures and Limb salvage has replaced amputation as the primary sur- longer length of inpatient rehabilitation stay were significantly gical treatment in severe limb trauma. This prospective cohort related to successful prosthetic ambulation. study examines the long-term outcomes of significant lower extremity injury (grade III tibial or ankle fractures, severe dys- van der Schans CP, Geertzen JH, Schoppen T, Dijkstra vascular and soft-tissue injury) treated either with amputation PU: Phantom pain and health-related quality of life in or limb salvage. The functional outcomes are similar between lower limb amputees. J Pain Symptom Manage 2002;24: the two treatment options; however, longer hospital stays, in- 429-436. creased number of complications, and more surgeries were found in the limb-salvage group. This study analyzed the determinants of health-related quality of life in a population of 437 lower extremity amputees using the RAND-36 Item Health Survey (Dutch Language Version) questionnaire. In general, the most important American Academy of Orthopaedic Surgeons 653

Limb Amputation and Prosthetic Rehabilitation Orthopaedic Knowledge Update 8 amputation-specific determinants of health-related quality of Czerniecki JM: Rehabilitation in limb deficiency: 1. Gait life were walking distance and stump pain. Amputees with and motion analysis. Arch Phys Med Rehabil 1996; phantom limb pain had poorer quality of life than those with 77(suppl 3):S3-S8. only phantom limb sensation. Edelstein JE, Berger N: Performance comparison Prosthetic Components and Prescription among children fitted with myoelectric and body- powered hands. Arch Phys Med Rehabil 1993;74:376- Carnesale PG: Amputation of the lower extremity, in 380. Canale ST (ed): Campbell’s Operative Orthopedics. Phil- adelphia, PA, Mosby, 2003, pp 575-595. Esquenazi A: Upper limb amputee rehabilitation and prosthetic restoration, in Braddom RL (ed): Physical This chapter examines the different levels of lower ex- Medicine and Rehabilitation. Philadelphia, PA, WB tremity amputations including their indications, techniques, Saunders, 2000, pp 263-278. and postoperative treatment. Noticeable differences occur in approaches taken in the nonischemic and ischemic lower ex- Gottschalk F: Transfemoral amputation: Biomechanics tremity. and surgery. Clin Orthop 1999;361:15-22. Schmaltz T, Blumentritt S, Tsukishiro K, Kocher L, Dietl Kane TJ III, Pollak EW: The rigid versus soft postopera- H: Energy efficiency of trans-femoral amputees walking tive dressing controversy: A controlled study in vascular on computer-controlled prosthetic knee joint: C-LEG. below-knee amputees. Am Surg 1980;46:244-247. Otto Bock Website. Available at: http:// www.ottobockus.com/products/lower_limb_prosthetics/ Leonard EI, McAnelly RD, Lomba M, Faulkner VW: c-leg_energy.pdf. Accessed June, 2004. Lower limb prosthesis, in Braddom RL (ed): Physical Medicine and Rehabilitation. Philadelphia, PA, WB This online article reviews a study of the energy expendi- Saunders, 2000, pp 279-311. ture needed for walking by six transfemoral amputees using several prosthetic devices including the C-Leg with electronic Leonard JA, Meier RH: Upper and lower extremity controls. prosthesis, in DeLisa JA, Gans BM (eds): Rehabilitation Medicine: Principles and Practice. Philadelphia, PA, Long-Term Prosthetic Rehabilitation Issues Lippincott-Raven, 1998, pp 669-697. Schoppen T, Boonstra A, Groothoff JW, deVries J, Pezzin LE, Dillingham TR, MacKenzie EJ: Rehabilita- Goeken LN, Eisma WH: Employment status, job charac- tion and the long-term outcomes of persons with teristics and work-related health experience of people trauma-related amputations. Arch Phys Med Rehabil with a lower limb amputation in the Netherlands. Arch 2000;81:292-300. Phys Med Rehabil 2001;82:239-245. Pinzur MS, Littooy F, Osterman H, Wafer D: Early post- This study examined the occupational status of lower limb surgical prosthetic limb fitting in dysvascular below- amputees in the Netherlands and compared the health experi- knee amputees with a pre-fabricated temporary limb. ence of working and nonworking amputees. Patients who Orthopedics 1988;11:1051-1053. stopped working because of the amputation had a worse health experience compared with those who continued to Yuksel F, Kislaoglu E, Durak N, Ucar C, Karacaoglu E: work. Patients who later returned to work, reported problems Prevention of painful neuromas by epineural ligatures, (such as finding a suitable job or obtaining workplace modifi- flaps and grafts. Br J Plast Surg 1997;50:282-185. cations) stemming from the long delay between the amputa- tion and the return to work. Classic Bibliography Carabelli RA, Kellerman WC: Phantom limb pain: Re- lief by application of TENS to contralateral extremity. Arch Phys Med Rehabil 1985;66:466-467. 654 American Academy of Orthopaedic Surgeons

Chapter 55 Musculoskeletal Rehabilitation Tom G. Mayer, MD Joel Press, MD Levels of Care patients who have chronic disabling musculoskeletal pain that does not respond to early surgical and/or non- Nonsurgical care for patients with injuries to the spine surgical intervention. Because this group of patients is and extremities can be classified into three distinct lev- often characterized by a complex mix of physical decon- els of treatment. Timing of the care is dependent on the ditioning, psychosocial and socioeconomic barriers to diagnosis and anticipated healing time from the inciting recovery, and some resistance to care, a multidisci- event. plinary approach is usually needed. Some patients re- quire a functional restoration approach, which includes Primary Care intensive physical training along with a cognitive behav- ioral disability management program aimed at increased Primary care is usually provided during an acute stage productivity. Measurement of function, narcotic detoxi- of an injury with pain control as the primary focus; fication, psychotropic medication, and infrequent injec- avoidance of deconditioning is also a consideration. The tions to relieve pain may be components of this ap- duration of the period of primary care depends on the proach. At the other extreme, palliative pain type of injury and can range from 10 to 14 days in pa- management usually involves a more passive role for tients with mild sprains, strains, and lacerations and the patient with an emphasis on pain-relieving injections from 8 to 12 weeks in patients with complex fractures and long-term use of opiates accompanied by a psycho- and dislocations. Treatment modalities include thermal social focus on deemphasizing the pain experience. Neu- (heat/cold) applications, pain medication and muscle re- roablative procedures and devices such as drug pumps laxants, immobilization, bed rest, traction, and injection and spinal cord stimulation also may be used. Chronic- methods. ity of symptoms is usually established by 6 months after injury; however, more functionally-based programs may Secondary Care be appropriate within 3 to 4 months of symptom onset if significant psychosocial or treatment resistance is evi- Secondary care is usually appropriate in the postacute dent. phase of an injury with the goal of providing reactiva- tion to prevent long-term physical deconditioning and Primary Rehabilitation psychosocial changes that could extend beyond the nor- mal healing period. This phase can begin when an injury The two main objectives of primary rehabilitation are to has undergone sufficient partial healing and/or stabiliza- control pain and to prepare the musculoskeletal system tion (through surgery, bracing, casting, or tissue healing) for proper healing from injury. Pain control can be ac- to permit progressive motion and strengthening exer- complished through the use of medications, physical cises. Active joint mobilization and strengthening of the modalities, injections, and occasionally bracing or rela- involved para-articular muscles are the primary modali- tive immobilization (fracture management). No single ties; treatment may be assisted with bracing, manipula- pain medication is effective for all injuries. With any tion, thermal modalities, medication, and injections. In medication, knowledge of the mechanism of action, side most patients, secondary care is the last component of effect profile, and interactions with other medications is musculoskeletal rehabilitation and is administered after essential for proper use. Acetaminophen (less than 4 an injury is treated nonsurgically or with surgery during mg/day) is an excellent first-line analgesic medication the acute stage of injury. for pain because of its low cost. Serious adverse effects are rare except for liver toxicity, which may occur with Tertiary Care prolonged use at a high dosage; particularly in associa- Tertiary care is the final phase of musculoskeletal reha- bilitation and is needed for only a small percentage of American Academy of Orthopaedic Surgeons 655

Musculoskeletal Rehabilitation Orthopaedic Knowledge Update 8 tion with substantial alcohol intake. Comparisons of ef- outcomes. It is essential to understand indications and fectiveness with nonsteroidal anti-inflammatory drugs contraindications of specific modalities when prescrib- (NSAIDs) are inconsistent. NSAIDs, all of which are ing these agents. In general, short-term use (1 to analgesic, antipyretic, and anti-inflammatory, show no 3 weeks) of physical modalities may be appropriate for significant differences among the various available com- an acute musculoskeletal problem or a flare-up of a pounds. Some patients reported a marked preference chronic condition. No single modality has been shown and variation in efficacy of different NSAIDs, thus war- to be superior to others for relief of musculoskeletal ranting a trial of a second or third class of medication if pain. Prolonged use of these passive modalities should one class provides no pain relief. An adequate trial of be discouraged. Newer treatments such as vertebral ax- NSAIDs may be 2 to 3 weeks. Several rare, serious ad- ial decompression and continuous passive motion have verse effects including clinical hepatitis, aplastic anemia, been purported to alleviate acute and chronic pain. Un- and agranulocytosis can occur. Gastrointestinal adverse til clinical studies confirm these findings, use of these effects are the most common and occur in approxi- treatments should be viewed as another physical modal- mately 25% of patients taking NSAIDs, whereas silent ity and treated accordingly. endoscopically demonstrated lesions occur in as many as 60% of patients. The overall risk for serious gas- Injections of a variety of medications in various ana- trointestinal bleeding in patients treated with NSAIDs tomic locations can be an adjunct to treating acute pain- is 1 per 1,000 patients, with the risk significantly greater ful musculoskeletal conditions. Epidural injections have in patients older than 65 years. been shown to be effective in reducing radicular pain; however, the results in some controlled, prospective Other medications used for acute pain symptoms studies are variable. The benefit of facet joint and sacro- with muscle spasms are muscle relaxants. These medica- iliac injections is controversial. They may provide some tions are centrally acting drugs, which produce nonspe- short-term pain relief that serves as an adjunct to other cific sedation that accounts for their muscle relaxation treatments (for example, manipulation, mobilization, effect. Although peripherally acting muscle relaxants ex- and exercise) by facilitating joint movement in other- ist (such as dantrolene sodium), these medications are wise hypomobile joints or segments. Trigger point injec- not used for musculoskeletal disorders because of po- tions may provide some temporary relief for tight, pain- tential severe adverse effects. Muscle relaxants have ful muscle spasms to allow earlier activation of the been found to be more effective than a placebo in the musculoskeletal system. Multiple, repeat injections with- relief of symptoms of acute musculoskeletal disorders. out concomitant activation of the patient is probably of Oral corticosteroids also may be useful as a strong anti- little benefit. inflammatory agent for patients with radicular symp- toms in the cervical and/or lumbar region. Short-term Secondary Rehabilitation use (7 to 10 days) or corticosteroids taken at a high dos- age (30 to 40 mg prednisone or equivalent) have not Secondary rehabilitation focuses on restoring function been associated with major adverse effects. Opioid anal- to the musculoskeletal system once initial pain symp- gesics, on occasion, can be used for acute pain symp- toms have subsided and tissue healing has been initi- toms. Opioid analgesics act primarily by binding opiate ated. No single component of musculoskeletal rehabili- receptors in the central nervous system and can be asso- tation is effective for every disorder; most disorders ciated with tolerance, toxicity, addiction, and illicit use require multiple components to provide a comprehen- with long-term administration. Even short-term use of sive program. Understanding the roles and skills of chi- these medications should be undertaken with caution ropractors, physical therapists, and other health care because of an association of adverse effects including providers is critical to avoid overuse and abuse of any demotivation, early reactive hyperalgesia, and early de- one treatment. Cornerstones of restoring function are pendency problems in a select group of patients. Al- activation of the patient to prevent the sequelae of im- though more potent than NSAIDs and acetaminophen, mobility and exercise to restore muscle flexibility, mus- in two of three clinical trials, narcotic analgesics were cle balance, and coordination. Initially, exercises are em- found to be no more effective than these medications in phasized in nonpainful ranges and planes of motion. relieving pain. The dosage schedule should be defined Manual treatments and mobilization of restricted joints and use limited to patients whose pain is unresponsive and soft tissues, either by chiropractors, osteopaths, ther- to alternative medications. apists, or physicians, are often initiated before beginning focused strengthening programs. Injections for pain con- Physical agents including ultrasound, electrical stim- trol (for example, local corticosteroids and epidural in- ulation, and heat and cold have been used to promote jections) may play some role in this phase of rehabilita- tissue healing, increase circulation, decrease inflamma- tion if the injections are used as an adjunct to increasing tion, and reduce pain. Although physical agents are fre- the patient’s active participation in therapy or exercise. quently used for symptomatic relief, these passive mo- Exercise programs for musculoskeletal rehabilitation dalities do not appear to have any effect on clinical 656 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 55 Musculoskeletal Rehabilitation should focus not only on mobility and absolute muscle should take place. This assessment should include all ap- strength but also on muscle balance (agonist and antag- propriate imaging tests, supportive electrodiagnostic onist strength ratios), kinetic chain issues (proximal and tests, and diagnostic injection procedures as needed. distal segment interplay with an injured segment), and Electromyography, nerve conduction velocity tests, muscle endurance or ability to function without fatigu- MRI, CT, myelography, diskography, selective nerve ing. Exercise programs should focus on strengthening root block, peripheral nerve block, and sympathetic weaker structures, with minimal aggravation of pain block tests may be included. Careful surgical decision- symptoms. Nonspecific exercise programs for nonspe- making and discussions with the patient and family cific diagnoses yield nonspecific and often unsuccessful about surgical options should then take place. If the pa- results. tient agrees to surgery, it should proceed with appropri- ate postoperative secondary care. Tertiary rehabilitation Repetitive flexion-biased exercises for a patient with is the last resort when all reasonable surgical interven- a typical posterolateral disk herniation may increase tions have been exhausted or the patient is unwilling to symptoms. Exercises that emphasize centralization of elect additional surgery. pain symptoms to the lumbar spine in patients with low back and leg symptoms may prove useful. The benefit of As a prelude to the tertiary rehabilitation process, determining the directional preference and proper plane special assessment of physical and functional capacity for flexion for each patient with back pain before initi- and psychosocial status is needed. From a physical per- ating exercise treatment has been well documented. A spective, patients have usually already undergone many recent study of patients with acute low back pain has weeks or months of physical therapy guided by a variety shown that a classification-based exercise program im- of health professionals and limited by resistance, fear, proved disability and returns to work status in the exer- and inhibition of function (often termed fear- cise group compared with a control group followed for 1 avoidance). During tertiary rehabilitation, the quantifi- year. Aerobic conditioning has been shown to be benefi- cation of physical function by objective measures may cial in terms of improving aerobic capacity, muscle help to guide the treatment approach by setting param- strength, and flexibility in patients with nonactive to eters for exercise, by providing feedback on progress to moderately active rheumatoid arthritis and osteoarthri- the patient, and by leading to better assessment of per- tis of the hip and/or knee. Short periods of immobiliza- manent impairment. Measurements of the mobility and tion immediately after surgery may be required for ade- strength around the injured joint(s) or spinal region(s), quate tissue healing. However, during the postoperative aerobic capacity, and the functional capacity of perform- period, and especially following anterior cruciate liga- ing various activities of daily living (such as lifting, grip- ment reconstruction, early rehabilitation to prevent loss ping, climbing) are important. Such tests are often of range of motion and muscle strength has been shown termed physical or functional capacity evaluations and to improve functional outcome. may involve goniometers, inclinometers, or three- dimensional digitizers to measure mobility; isometric, Physical conditioning programs, called work condi- isoinertial, or isokinetic strength testing devices; bicycle tioning or work hardening programs, attempt to im- or treadmill ergometers; and a variety of lifting proto- prove work status and function; however, there is no ev- cols and devices. In unmotivated patients or those with idence of their efficacy for acute back pain. Emphasis chronic pain, measurements of functional capacities may should be placed on use of programs that focus on re- not reflect their true physiologic functional abilities. turn to work. Patients should participate in restoration programs that simulate the activities of daily living that Psychosocial assessment is also an essential prereq- they need to perform, and emphasize improvement in uisite for planning tertiary rehabilitation. Traditionally, function. Programs that emphasize pain relief alone and clinicians have searched for causes of pain, seeking a that use short-term passive modalities are not effective. physical basis for pain complaints that, once identified, If no improvement is seen in a 4- to 6-week period with could be eliminated or blocked. When no organic basis physical conditioning or work hardening programs, was identified, a psychological cause was assumed, other options such as tertiary rehabilitation should be hence the term psychogenic pain. However, the concept considered. of a simple dichotomy, that pain is physical or psycho- logical, is inadequate. It is more accurate and clinically Tertiary Rehabilitation effective to identify a variety of psychosocioeconomic barriers to recovery or risk factors creating entitlement, Multidisciplinary Assessment resistance, or fear-avoidance. A variety of simple vali- dated questionnaires have been developed that can be Because the diagnosis in patients with chronic pain or used to assess pain, disability, health status, and depres- disability may be multifactorial, the involvement of sion (Table 1). A psychiatric diagnosis can be made us- many health professionals is often required. Before in- ing the Structured Clinical Interview for the Diagnostic stituting a tertiary rehabilitation program, a multidisci- and Statistical Manual of Mental Health Disorders, plinary assessment of the patient’s treatment options American Academy of Orthopaedic Surgeons 657

Musculoskeletal Rehabilitation Orthopaedic Knowledge Update 8 TABLE 1 | Questionnaires Available for Patient Physical and erature. These programs use the measurement of physical Psychological Assessment and functional capacity to guide the rehabilitation ap- proach quantitatively, limiting the amount of exercise so Pain Drawing Questionnaire that patients neither exert excessive efforts nor do so lit- Oswestry Low Back Pain Disability Questionnaire tle that their time is wasted. Quantification removes some Roland-Morris Disability Questionnaire of the subjectivity inherent in allowing patients to remain Medical Outcomes Study 36-Item Short Form in treatment who are giving only a negligible effort while Million Disability Questionnaire claiming they are “doing their best.”A supportive psycho- logical and case management program must provide ed- fourth edition. Significant psychopathology has been ucation about pain control and stress management tech- noted in chronic pain patients. A psychological inter- niques, provide treatment to resolve the disability, view conducted by a clinical psychologist who considers reintegrate the patient into the work force, become in- identified risk factors for ongoing disability may be use- volved in school or training as needed, and help in case ful. Personality changes may be manifested by anger, settlement efforts. Modalities that may enhance mobility hostility, noncompliance, and resistance to the efforts of or help to control pain, such as intra-articular injections, the therapeutic team. Minor head injuries, organic brain transcutaneous electrical nerve stimulation, and anti- dysfunction, and a history of alcohol or drug use can inflammatory or psychotropic medications may prove to produce cognitive errors and dysfunctions, which could be valuable adjuncts to such programs. Objectively doc- create clinical management problems and make the pa- umented outcomes that show return to productivity are tient refractory to education. the measure of success. Outcome measures for functional restoration programs include work status (for example, re- Finally, it is imperative that the orthopaedic surgeon turn to work and work retention), future healthcare sys- is aware of the influence of the disability system, which tem use (for example, additional surgery to the injured may create a variety of incentives and disincentives to area, persistent healthcare-seeking behavior, number of expected behaviors in treatment. Knowledge of the pa- visits to new providers), recurrent injury after work return tient’s involvement with the workers’ compensation sys- (for example, new claims and lost time) and case closure tem (state or federal) and the key factors associated (workers’ compensation and third-party claims). Re- with this system is needed for proper assessment. It peated use of pain or disability questionnaires may be use- should be determined if the patient is receiving current ful, but should become the primary outcome measure only temporary total disability benefits, impairment or dis- if the patient has no outstanding disability issues. ability benefits, vocational rehabilitation benefits, or is approaching a variety of financial and medical end Palliative Pain Management points (termed maximum medical improvement or per- manent and stationary status). The case manager, adjus- Many pain management specialists and pain clinics fo- tor, or attorney for the injured worker may be a valu- cus on palliation of pain rather than restoration of func- able resource for information about case status. Other tion. Efforts usually are focused on helping the patient financial benefits from private short- or long-term dis- reduce stress and tension while accepting a relatively ability insurers, federal disability systems (Supplemental nonfunctional lifestyle. Multidisciplinary assessment Security or Social Security Disability benefits), or from may result in recommendations for procedures that may a variety of third parties (such as auto or product liabil- not be beneficial to functional recovery, but which may ity insurance) may affect patient motivation and behav- ameliorate pain. These may include a variety of neuro- ior. ablative procedures, radiofrequency neurotomies in the spine, spinal cord stimulation, or the use of intrathecal Functional Restoration Approaches drug pumps. Treatment programs generally focus on psychological interventions, with only minimal physical Functional restoration approaches to tertiary rehabilita- rehabilitation. Although the physical component of tion are oriented toward recovery from disability as well functionally-oriented rehabilitation usually has greater as pain control. The physical and psychological compo- intensity and more elements of supervision than second- nents of disability are known to be a source of much of ary care options, physical components in palliative pain the disability and it is believed that regaining greater phys- management rely more on elements of primary care ical capacity, particularly in the injured “weak link,” com- (manipulation, acupuncture, massage, and thermal mo- bined with multimodal disability management will ulti- dalities) or very light exercise (aqua therapy, light mately reduce pain perception. A temporary increase in stretching). Contributing to the limited physical aspects pain during treatment is considered acceptable. Such pro- of these programs is a tendency to rely on narcotics as grams have increased in popularity over the past 2 de- an active component of pain control, with acceptance of cades, with multiple outcome studies available in the lit- long-term narcotic use as a permanent component of 658 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 55 Musculoskeletal Rehabilitation the patient’s medical care. Although psychotropic drugs classification-based approach resulted in improvement in dis- and NSAIDs may also be used, the type of narcotic and ability and return-to-work status after 4 weeks as compared dosage tends to determine much about the patient’s ul- with therapy based on clinical guidelines. timate physical and psychological well-being. The regu- lar use of continuous release narcotics (for example, Secondary Rehabilitation methadone, meperidine hydrochloride, hydromorphone hydrochloride), or narcotic pumps is a rapidly growing Mayer T, Polatin P, Smith B, et al: Spine rehabilitation: trend. Psychologic therapies focus on stress manage- Secondary and tertiary nonoperative care. Spine J 2003; ment and learning techniques to cope with inactivity 3(suppl 3):28S-36S. and lack of societal productivity, even in younger indi- viduals. Federal disability benefits (Supplemental Secu- This Contemporary Concepts Review presents a position rity or Social Security Disability benefits) provide a statement of the North American Spine Society Board and safety value for those with preretirement disabilities, summarizes aspects of secondary and tertiary rehabilitation with the number of patients receiving such payments in- specific to spinal disorders in greater detail. creasing from four million to nine million in the United States over the past 20 years. These benefits have in- van Tulder MW, Malmivaara A, Esmail R, Koes BW: Ex- creased from $40 billion to $100 billion over the same ercise therapy for low back pain, in The Cochrane Li- time period, now accounting for 5% of the US federal brary (Update Software on CD-ROM), Issue 3, 2003. budget. Outcome measurement may be problematic, be- cause the patient’s self-assessment of pain and health Thirty-nine randomized controlled trials were identified. status may be markedly influenced by the treatment Exercise therapy was shown to be more effective than the team and requirements for continued narcotic use. usual care given by general practitioners and equally effective as conventional physiotherapy for chronic low back pain. Ex- ercises may be helpful for patients with chronic low back pain to facilitate earlier return to normal daily activities and work. Summary Tertiary Rehabilitation Primary rehabilitation focuses on control of painful Anagnostis C, Mayer T, Gatchel R, Proctor TJ: The Mil- symptoms and prevention of sequelae of extensive im- lion Visual Analog Scale: Its utility for predicting ter- mobility. Secondary rehabilitation stresses early reacti- tiary rehabilitation outcomes. Spine 2003;28:1051-1060. vation of the patient with emphasis on stabilizing the in- jured area while improving flexibility, strength, When a validated disability outcome questionnaire is endurance, and coordination skills. Tertiary care is re- given to a group of patients with chronic disabling spinal dis- served for patients with chronic disabling musculoskele- orders before and after tertiary rehabilitation, excellent pre- tal pain that require a more comprehensive and often dictive value for socioeconomic outcomes (work status, health multidisciplinary approach to improve function even if system usage, recurrent injury 1 year after treatment) is identi- some pain symptoms persist. Palliative care is provided fied, particularly in patients who report high levels of disability when functional progress is no longer deemed feasible. immediately after treatment. Annotated Bibliography Dersh J, Gatchel RJ, Polatin P: Chronic spinal disorders and psychopathology: Research findings and theoretical General considerations. Spine J 2001;1:88-94. McGill SM: Low Back Disorders: Evidence-Based Pre- This prospective study of the prevalence of psychopathol- vention and Rehabilitation. Human Kinetics, Cham- ogy in a large sample of chronically disabled patients with paign, IL, 2002. work-related spinal disorders uses a validated clinician- administered instrument for psychiatric diagnosis. The Struc- This book includes information on epidemiologic studies tured Clinical Interview for the Diagnostic and Statistical Man- on low back disorders, relevant functional anatomy and nor- ual of Mental Disorders, fourth edition was used. mal and injury mechanics of the lumbar spine, scientifically based approaches to back pain prevention at work, and low Jouset N, Fanello S, Bontoux L, et al: Effects of func- back rehabilitation. tional restoration versus 3 hours per week of physical therapy: A randomized controlled study. Spine 2004;29: Primary Rehabilitation 487-494. Fritz JM, Delitto A, Erhard RE: Comparison of A functional restoration multidisciplinary approach featur- classification-based physical therapy with therapy based ing physical training and disability management proved better on clinical practice guidelines for patients with acute than therapy alone in a randomized controlled trial assessed low back pain. Spine 2003;28:1363-1371. by quantifiable outcomes. Seventy-eight patients randomly received therapy based Proctor TJ, Mayer TG, Gatchel RJ, McGeary DD: Unre- on a classification system or clinical practice guidelines. For mitting health-care-utilization outcomes of tertiary re- patients with acute, work-related low back pain, the use of a American Academy of Orthopaedic Surgeons 659

Musculoskeletal Rehabilitation Orthopaedic Knowledge Update 8 habilitation of chronic musculoskeletal disorders. J Bone Mayer T, Gatchel R, Polatin P: Occupational Musculosk- Joint Surg Am 2004;86:62-69. eletal Disorders: Function, Outcomes and Evidence. Lip- pincott Williams & Wilkins, Philadelphia, PA, 1999. Comparison of patients who persistently seek health care after tertiary rehabilitation with those who do not reveals that Mayer T, Gatchel R, Polatin P, Evans T: Outcomes com- persistent healthcare seekers demonstrate poor outcomes in parison of treatment for chronic disabling work-related work-related injuries that lead to higher societal costs and de- upper extremity disorders and spinal disorders. J Occup creased worker productivity. Environ Med 1999;41:761-770. Schonstein E, Kenny D, Keating J, Koes B, Herbert RD: Mayer T, McMahon MJ, Gatchel RJ, Sparks B, Wright Physical conditioning programs for workers with back A, Pegues P: Socioeconomic outcomes of combined and neck pain: A Cochrane systematic review. Spine spine surgery and functional restoration in workers’ 2003;28:E391-E395. compensation spinal disorders with matched controls. Spine 1998;23:598-606. A meta-analysis by the Cochrane collaboration of ran- domized trials of chronic back pain in work-related injuries Mayer TG, Gatchel RJ, Mayer H, Kishino N, Keeley J, demonstrates that physical conditioning programs that incor- Mooney V: A prospective two-year study of functional porate a cognitive behavioral approach reduce work loss. restoration in industrial low back injury: An objective assessment procedure. JAMA 1987; 258:1763-1767. Classic Bibliography Mazanec D: Medication use in sports rehabilitation, in Bendix AE, Bendix T, Haestrup C, Busch E: A prospec- Kibler WB, Herring SA, Press JM (eds): Functional Re- tive, randomized 5-year follow-up study of functional habilitation of Sports and Musculoskeletal Injuries. restoration in chronic low back pain patients. Eur Spine Gaithersburg, MD, Aspen, 1998, pp 71-79. J 1998;7:111-119. O’Sullivan PB, Phyty GD, Twomey LT, Allison GT: Eval- Hazard RG, Fenwick JW, Kalisch SM, et al: Functional uation of specific stabilizing exercise in the treatment of restoration with behavioral support: A one-year pro- chronic low back pain with radiologic diagnosis of spective study of patients with chronic low-back pain. spondylolysis or spondylolisthesis. Spine 1997;22: Spine 1989;14:157-161. 2959-2967. Jordan KD, Mayer TG, Gatchel RJ: Should extended disability be an exclusion criterion for tertiary rehabili- tation? Socioeconomic outcomes of early versus late functional restoration in compensation spinal disorders. Spine 1998;23:2110-2117. 660 American Academy of Orthopaedic Surgeons

Chapter 56 Genetic Diseases and Skeletal Dysplasias William G. Mackenzie, MD R. Tracy Ballock, MD Introduction months to achieve stability has been recommended for children younger than 6 years. Surgical intervention for The recent advances in the fields of human and mouse this type of hip dislocation has a high failure rate and genetics and molecular biology have led to rapid has not been shown to improve outcomes. progress in understanding the etiology and pathogenesis of many human skeletal dysplasias and other genetic Other musculoskeletal disorders occurring in chil- diseases affecting the skeleton. Some of these new find- dren with Down syndrome are also the result of excess ings relate to the diagnosis and treatment of children ligamentous laxity and joint instability. Patellofemoral with inherited disorders affecting the skeleton. subluxation and dislocation may develop in the absence of symptoms. Soft-tissue reconstruction alone is fre- Trisomy 21 (Down Syndrome) quently unsuccessful in preventing recurrent instability. Pes planovalgus and hallux valgus are also common and Duplication of a portion of the long arm of chromosome usually respond to shoe wear modifications. 21 occurs once every 800 to 1,000 live births and results in the disorder known as Down syndrome. The most com- Turner’s Syndrome mon chromosomal abnormality in humans, Down syn- drome can be diagnosed prenatally by amniocentesis. In 1 of every 3,000 live births, a single X chromosome Postnatal diagnosis can be made by recognition of the (XO) is present instead of the normal XX or XY combi- characteristic facies (upward slanting eyes, epicanthal nation, resulting in Turner’s syndrome. Patients are phe- folds, and a flattened profile) as well as the single trans- notypically females with short stature, a webbed neck, verse flexion crease in the palm (simian crease).Although mental retardation is usually associated with Down syn- Figure 1 MRI showing spinal cord compression in a 12-year-old girl with Down syn- drome, the degree of mental deficiency is variable. Other drome. An os odontoideum (arrow) has become lodged between the ring of C1 and the abnormalities may include congenital heart disease, dens. The patient had hyperreflexia but was otherwise neurologically intact. duodenal atresia, hypothyroidism, and hearing loss. Children with Down syndrome may develop muscu- loskeletal problems as a result of the increased ligamen- tous laxity that occurs with this condition. Approximately 10% of patients will exhibit asymptomatic atlantoaxial in- stability. Therefore, it is recommended that children with Down syndrome have screening flexion-extension radio- graphs of the cervical spine obtained before athletic par- ticipation. Spinal cord compression is rare, and surgical in- tervention is reserved for children who exhibit symptoms of myelopathy (Figure 1). In addition to C1-C2 instability, children with Down syndrome also may develop hip instability. Unlike typi- cal hip dysplasia in which the shallow acetabulum allows progressive migration of the femoral head out of the socket, in children with Down syndrome the hip may dislocate out of an acetabulum that may be only mildly dysplastic. This is possible because of the degree of liga- mentous laxity present. Brace treatment for 6 to 8 American Academy of Orthopaedic Surgeons 663

Genetic Diseases and Skeletal Dysplasias Orthopaedic Knowledge Update 8 Table 1 | Diagnostic Criteria for Neurofibromatosis 1 in children age 6 years or younger. Nondystrophic scoli- osis in younger children can modulate into the dystro- Six or more café-au-lait spots whose greatest diameter is 5 mm in pre- phic type over several years. Radiographic features of pubertal and 15 mm in postpubertal patients dystrophic scoliosis include scalloping of the vertebral Two or more neurofibromas of any type or one plexiform neurofibroma end plates, foraminal enlargement, and penciling of the Axillary freckling ribs. These dystrophic curves are notoriously resistant to Optic glioma brace treatment and will progress if not treated by early Two or more Lisch nodules (iris hamartomas) anterior and posterior fusion. Preoperative MRI is es- A distinctive osseous lesion sential to identify areas of dural ectasia and intraspinal A first-degree relative with neurofibromatosis 1 neurofibromas. and a low hairline. Girls with Turner’s syndrome do not Hereditary Multiple Exostosis pass through puberty or develop secondary sexual char- acteristics because of the lack of sex steroid hormones. Hereditary multiple exostosis (HME) is an autosomal Cubitus varus is a common finding in Turner’s syndrome dominant disorder with a prevalence of 1 in 50,000 pa- but rarely requires treatment. Scoliosis may also de- tients. Bony projections with cartilage caps develop near velop and management is similar to that for idiopathic the ends of multiple long bones (Figure 3). These exos- curves. toses continue to grow until skeletal maturity is reached, and they may cause partial growth inhibition in Neurofibromatosis the adjacent physis, resulting in limb deformity, limb- length discrepancy, and occasionally subluxation of an Neurofibromatosis (NF) is divided into two distinct clin- adjacent joint. Although initially a benign lesion, the ical entities, NF1 and NF2. NF1 is the most common sin- risk of transformation to a malignant chondrosarcoma gle gene disorder, occurring once in every 3,000 births, or osteosarcoma has been estimated at 0.5% to 3%, and it results from a mutation in the gene encoding a which is higher than the general population risk. protein now known as neurofibromin. Neurofibromin helps regulate cell growth through modulation of the HME is caused by mutations in EXT1 or EXT2, Ras signaling pathway. The diagnosis of NF1 relies on members of a newly described family of putative tumor identification of up to six clinical criteria (Table 1). suppressor genes that encode glycosyltransferases. Common clinical findings include café-au-lait macules, EXT1 and EXT2 proteins have been localized by immu- axillary freckles, Lisch nodules of the iris, and neurofi- nohistochemical techniques to the Golgi apparatus of bromas. Malignant transformation of a neurofibroma to the cell, where they form a protein complex that is re- a neurofibrosarcoma results if a somatic mutation oc- sponsible for the biosynthesis of heparan sulfate gly- curs in the remaining normal copy of the gene. There- cosaminoglycans. The consequence of the disease- fore, neurofibromas that enlarge suddenly or become causing mutations is loss of heparan sulfate on the cell painful should be managed as potential sarcomas. surface, where the molecule frequently functions as a coreceptor for peptide growth factors to increase bind- The typical bone lesion in neurofibromatosis is an ing affinity. anterolateral bowing deformity of the tibia that may progress to pseudarthrosis (Figure 2). Prophylactic brac- Although EXT genes are ubiquitously expressed, the ing with a total contact orthosis is recommended to di- disease appears to only result in aberrant proliferation minish the likelihood of pseudarthrosis formation. Once of growth plate chondrocytes. Histologically, abnormal a pseudarthrosis is established, bone grafting with in- cytoskeletal inclusions consisting of actin and α-actinin tramedullary fixation is the initial treatment. For persis- are found in chondrocytes comprising the cartilage cap. tent pseudarthroses, either a vascularized bone graft or The relationship between this observation and the aber- bone transport by distraction osteogenesis may be re- rant chondrocyte proliferation is unclear, however. Re- quired for healing. Although amputation and prosthetic cently it has been demonstrated that the Drosophila fitting for recalcitrant pseudarthrosis may result in im- EXT1 homolog tout-velu is necessary for the diffusion proved lower extremity function over these salvage of the hedgehog protein in the developing wing tissue of techniques, this is not commonly performed. the fly by affecting the transduction of the hedgehog signal across adjacent cells. Therefore, EXT mutations Scoliosis occurs commonly in children with neurofi- may also affect the function of the Indian hedgehog bromatosis, and it is classified as either dystrophic or protein in the growth plate, whose role is to modulate nondystrophic. Nondystrophic curves resemble idio- the rate at which chondrocytes stop proliferating and pathic scoliosis and are managed in a similar fashion. differentiate into hypertrophic cells. Dystrophic curves are short and sharp, occurring over four to six spinal levels, and represent 80% of scoliosis Current genetic observations indicate that HME may not be a true chondrodysplasia, but rather a neo- plastic condition. According to the Knudsen “two-hit” 664 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 56 Genetic Diseases and Skeletal Dysplasias Figure 2 Radiograph showing anterolateral bowing in a child with neurofibromatosis, which progressed to congenital pseudarthrosis of the tibia. model of tumor suppressor gene inactivation in cancer, both copies of the gene must be inactivated to abolish the normal tumor suppressor activity. In hereditary can- cer, the first hit usually consists of a germline mutation, whereas the second hit is the inactivation of the remain- ing wild-type copy through a somatic mutation. This model has recently been applied to patients with HME. An inherited haploinsufficiency (malfunction of one of the two working copies of a gene within the cell) com- bined with a subsequent loss of function in the remain- ing copy of the gene through a somatic mutation is re- quired for osteochondroma formation. The growth dysregulation that ensues then predisposes the cell to further genetic alterations, resulting in chondrosarcoma in a small percentage of patients. Skeletal Dysplasias Figure 3 Typical radiographic appearance of multiple osteochondromas around the knees in a patient with hereditary multiple exostosis. Achondroplasia and Related Disorders Several chondrodysplasia phenotypes result from muta- tions in the fibroblast growth factor receptor 3 gene, in- American Academy of Orthopaedic Surgeons 665

Genetic Diseases and Skeletal Dysplasias Orthopaedic Knowledge Update 8 Figure 4 Typical clinical (A) and radiographic (B) findings in a child with achondroplasia. cluding achondroplasia, hypochondroplasia, thanato- achondroplasia involves the proximal limb bones, in- phoric dysplasia, and severe achondroplasia with cluding the humerus and femur, whereas children with developmental delay and acanthosis nigricans dysplasia. other disorders have mesomelia (shortening of the fore- These disorders are closely related and represent a con- arm and leg) and acromelia (shortening of the hands tinuum of severity. and feet). The diagnosis is often made prenatally by ul- trasound; if not identified prenatally, this disorder is Achondroplasia identified at birth by the presence of rhizomelic short- Achondroplasia, the most common form of dwarfism, is ening, a trunk of normal length, macrocephaly, frontal an autosomal dominant disorder that is caused by a sin- bossing, a depressed nasal bridge, and trident hands gle nucleotide substitution. More than 90% of instances (Figure 4). Elbow flexion contractures are the result of of achondroplasia result from a sporadic mutation. The bowing of the distal humerus and posterior radial head specific mutation in achondroplasia converts either gua- subluxation/dislocation. Classic radiographic findings in- nine to arginine or guanine to cysteine at position 380 in clude shortening of the long bones, progressive narrow- the transmembrane domain of the protein, resulting in a ing of the interpedicular distance through the lumbar glycine to arginine substitution. This single amino acid spine, squared iliac wings, horizontal acetabula, and nar- substitution not only causes stabilization of the fibro- row sacrosciatic notches. blast growth factor receptor protein and its accumula- tion on the cell surface, but also results in uncontrolled, Foramen magnum and upper cervical stenosis is a prolonged ligand-dependent activation of the receptor. life-threatening disorder that affects these children at The result of this sustained fibroblast growth factor re- birth and in early life. Cervicomedullary cord compres- ceptor activity is growth retardation in the proliferative sion can result in hypotonia, delayed development, zone of the growth plate, leading to decreased bone weakness, and apnea. The central apnea can be compli- length. The most profound effect on the skeleton is in cated by obstructive components, including abnormal the areas of greatest endochondral growth (humerus nasopharyngeal development and enlarged tonsils and and femur), resulting in the characteristic rhizomelia. adenoids. Routine perinatal screening with MRI is con- The rhizomelic pattern of shortening in children with troversial. Symptomatic children are typically assessed with MRI and a sleep study. Surgical management in- 666 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 56 Genetic Diseases and Skeletal Dysplasias Figure 5 A and B Radiographs showing spontaneous correction of thoracolumbar kyphosis. cludes decompression and occasionally shunting for hy- with thoracolumbar kyphosis and those with significant drocephalus. Unlike other forms of skeletal dysplasias, degenerative changes. Scoliosis is unusual in this patient cervical instability is rare. population. Thoracolumbar kyphosis occurs commonly in in- Genu varum is typical in over 90% of patients with fants. It is thought to be secondary to truncal hypotonia achondroplasia. The deformity may occur at multiple and weakness and an enlarged head. Avoidance of levels, including the distal femur, the proximal and distal propped sitting is advocated. The kyphosis typically re- tibia, and through the lateral ligaments of the knee. Re- solves as children achieve independent ambulation alignment osteotomies are recommended for patients (later than in children of average stature with achondro- with progressive, symptomatic genu varum. Correction plasia who typically have a mean walking age range of of the associated internal tibial torsion is done concur- 18 to 24 months) (Figure 5). rently. Bracing is reserved for those children with severe Short stature in achondroplasia is moderately severe progressive kyphosis and wedging of the apical verte- and can result in functional limitations. Teenagers with bra. Anterior and posterior spinal fusion is indicated in achondroplasia have concerns about their body image. older children with persistent severe kyphosis, but it is Adult studies indicate that function and self-image in rarely required. Lumbar spinal stenosis is common patients with achondroplasia are similar to those of (30% of children are symptomatic in the second de- average-statured adults. Growth hormone has been ad- cade), and it is caused by interpedicular narrowing, vocated in growing children, but its use is controversial short pedicles, disk bulging, and hyperlordosis. In older because the improvement in final height is variable. Ex- patients, the stenosis is aggravated by degenerative tended limb lengthening to increase stature has been changes. Lumbosacral decompression is recommended used commonly in Europe, but is more controversial in for patients with symptomatic spinal stenosis. Spinal fu- North America. Long-term effects on the adjacent artic- sion is required in addition to decompression in patients ular surfaces have not been well studied. American Academy of Orthopaedic Surgeons 667

Genetic Diseases and Skeletal Dysplasias Orthopaedic Knowledge Update 8 clude rhizomelic shortening, macrocephaly, platy- spondyly, and severe restrictive lung disease resulting from a small thoracic cavity. Severe Achondroplasia With Developmental Delay and Acanthosis Nigricans Dysplasia Children with severe achondroplasia with developmen- tal delay and acanthosis nigricans dysplasia exhibit ex- treme short stature, developmental delay, acanthosis ni- gricans, and genu varum. Dysplasias Secondary to Type II Collagen Abnormalities This spectrum of disorders includes spondyloepiphyseal dysplasia congenita, spondyloepimetaphyseal dysplasia, and Kniest dysplasia. Figure 6 Photograph showing typical clinical appearance of a child with spondyloepi- Spondyloepiphyseal Dysplasia physeal dysplasia congenita. Spondyloepiphyseal dysplasias are characterized by short stature secondary to a short trunk and short limbs. Hypochondroplasia Many different types of this disorder exist, with the Hypochondroplasia is an autosomal dominant disorder most common type being the congenita form. This is with clinical features and radiographic findings similar caused by mutations in COL2A1 (collagen type II α 1 to those associated with achondroplasia, but to a milder chain). This gene encodes type II collagen, which is degree. The diagnosis is rarely apparent before age found primarily in cartilage and in the vitreous humor, 2 years and typically results from investigation of short locations consistent with the phenotype of spondyloepi- stature. Musculoskeletal problems that present for man- physeal dysplasia congenita and other disorders such as agement in hypochondroplasia include lumbar spinal Kniest dysplasia and type I Stickler’s syndrome. Radio- stenosis, genu varum, and short stature. Management of graphic changes include abnormal spinal development hypochondroplasia is the same as for the disorders asso- with odontoid hypoplasia and platyspondyly, abnormal ciated with achondroplasia. formation of the long bone epiphyses with variable metaphyseal involvement, and generalized delay in epi- Thanatophoric Dysplasia physeal ossification. The diagnosis is made at birth. Pa- Thanatophoric dysplasia is a severe, usually lethal disor- tients have marked short stature with a very short trunk der resulting from mutations in the fibroblast growth and often a barrel-shaped chest (Figure 6). Lumbar lor- factor receptor 3. Clinical features of this dysplasia in- dosis is typical, and progressive kyphoscoliosis occurs. Retinal detachment, severe myopia, and sensorineural hearing loss are common in childhood and adult life. Atlantoaxial instability resulting from odontoid hypo- plasia and ligamentous laxity must be evaluated early in life and monitored on a regular basis with flexion- extension lateral C-spine radiographs and/or MRI. Surgi- cal management is indicated in patients with significant instability or cervical myelopathy. Progressive kypho- scoliosis in the growing child can be managed with a brace; however, with progression, surgical management is usually required. Lower extremity malalignment is common in these children. Coxa vara, genu valgum, valgus alignment of the distal tibia, and planovalgus foot deformities are typical. These deformities can result in significant gait ab- normalities consisting of increased lumbar lordosis, a wad- dling gait, and a crouch gait with the knees knocking to- gether. The coxa vara is often progressive and is difficult to assess radiographically because of the delayed capital femoral ossification (Figure 7). 668 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 56 Genetic Diseases and Skeletal Dysplasias When considering realignment of the lower extremi- ties, deformity at the hip, knee, and ankle must be con- sidered and managed together. Abnormal epiphyseal development typically results in early osteoarthritis of the weight-bearing joints, and most young adults require total joint arthroplasty. There is no evidence that re- alignment osteotomies will delay the need for joint ar- throplasty. An uncommon tarda form of spondyloepiphyseal dysplasia is milder and presents later in the first decade of life. This form has X-linked inheritance and is caused by a mutation in the SEDL gene, which is thought to be involved in vesicle transport from the endoplasmic retic- ulum to the Golgi apparatus. Patients with this type of spondyloepiphyseal dysplasia present with deformities that are milder but similar to those of patients with spondyloepiphyseal dysplasia congenita. In this patient population, the upper cervical spine must be assessed, scoliosis may develop, and osteoarthritis frequently oc- curs in later life. Kniest Dysplasia Kniest dysplasia is an autosomal dominant disorder caused by mutations in COL2A1. The trunk is dispro- portionately shorter than the limbs in patients with Kni- est dysplasia, and the face is flattened with midface hy- poplasia. Myopia, retinal detachment, deafness, joint contractures, limb malalignment, and kyphoscoliosis can occur throughout life in this patient population. The ra- diographic features include dumbbell-shaped long bones with broad metaphyses and irregular dysplastic epiphy- ses. Joint stiffness and pain typically result from deterio- ration of the articular cartilage. Metaphyseal Chondrodysplasia Figure 7 Radiograph showing coxa vara in a child with spondyloepiphyseal dysplasia congenita. Although many forms of metaphyseal dysplasia have been described, metaphyseal involvement with short mutation of RMRP, a nuclear gene (RNA component of stature and bowing of the legs is a common feature to mitochondrial RNA processing endoribonuclease). Pa- all. The most common Schmid type is autosomal domi- tients with this disorder have fine, sparse body hair and nant and is caused by a type X collagen mutation significant complications, including impaired cellular im- (COL110A1). This type is the mildest in this group, with munity, anemia, Hirschsprung’s disease, and malignancy. patients typically exhibiting moderate short stature, a Patients with metaphyseal chondrodysplasia may need waddling gait, and genu varum. The diagnosis is usually surgical management of short stature and limb malalign- made in early childhood. The radiographic features re- ment (Figure 8). semble those seen in patients with rickets and include metaphyseal irregularity and flaring with widening of Pseudoachondroplasia the physes. Pseudoachondroplasia is an autosomal dominant disor- The Jansen type is a rare autosomal dominant disor- der caused by a mutation in the gene encoding for carti- der caused by a mutation in the parathyroid hormone lage oligomeric matrix protein (COMP). COMP is an receptor gene that regulates the differentiation of extracellular calcium-binding glycoprotein belonging to growth plate chondrocytes. Severe short stature with de- formity is typical, and some affected children have hy- percalcemia, hypercalciuria, and hyperphosphaturia. The McKusick type is an autosomal recessive disor- der (also called cartilage-hair hypoplasia) caused by a American Academy of Orthopaedic Surgeons 669

Genetic Diseases and Skeletal Dysplasias Orthopaedic Knowledge Update 8 Figure 9 Radiographic appearance of the hips of a patient with multiple epiphyseal dysplasia. Figure 8 Radiographic appearance of the knees of a patient with Jansen metaphy- be observed. Limb alignment procedures are indicated seal chondrodysplasia. for patients with severe progressive deformities that in- terfere with function, but there is a high rate of recur- the thrombospondin family, and it is involved in chon- rence because of ligamentous laxity and abnormal bone drocyte migration and proliferation. The COMP mole- growth. Early arthritis resulting in hip arthroplasty oc- cule is composed of five flexible arms with large globu- curs in about one third of patients with this disorder by lar domains at the end of each arm, resembling a the fourth decade of life. bouquet of flowers. Mutations affecting the type III re- peat region or C-terminal domain of the protein result Multiple Epiphyseal Dysplasia in decreased calcium binding caused by a structural change in the protein. Approximately 30% of patients Multiple epiphyseal dysplasia (MED) describes a spec- have an in-frame deletion mutation, resulting in four as- trum of autosomal dominant disorders characterized by partic acid residues instead of five at amino acids 469 epiphyseal dysplastic changes resulting in mild to mod- through 473 of the protein. It is interesting to note that erate short stature, genu valgum, and early onset os- mutations in the COMP gene have also been discovered teoarthritis. Short, hyperextensible fingers are present in in patients with multiple epiphyseal dysplasia. This sug- patients with severe involvement. The diagnosis is usu- gests that pseudoachondroplasia and multiple epiphy- ally made in midchildhood, with reports of pain and seal dysplasia, although originally described as distinct joint stiffness in patients with short stature. Radiographs disorders, are now recognized as part of a disease spec- demonstrate delayed epiphyseal ossification with subse- trum. quent irregular development of the epiphyses. The spine is usually not affected. The clinical phenotypes are vari- Children with pseudoachondroplasia have a short able, ranging from mild epiphyseal abnormalities in the trunk and short limb dysplasia that is not usually diag- hips that can lead to a misdiagnosis of bilateral Legg- nosed until early childhood. Atlantoaxial instability is Calvé-Perthes disease to severe widespread epiphyseal common. Generalized ligamentous laxity is present, and dysplasia with joint contractures, osteoarthritis, and this is particularly noticeable in the hands (the fingers short stature. are short and hypermobile). Radiographic features in- clude shortening of the long bones with irregular, ex- In the hips of children with MED, capital femoral os- panded metaphyses and small fragmented epiphyses. sification is delayed with subsequent fragmented ossifi- Evidence of platyspondyly can be observed with unique cation, and it eventually coalesces to form an intact but anterior projections. Genu valgum, genu varum, or small ossific nucleus. Although the radiographic appear- windswept deformities of the lower extremities can also ance in the fragmented stage appears similar to that seen in patients with Legg-Calvé-Perthes disease, the typical stages of sclerosis, collapse, fragmentation, and reossification are not apparent (Figure 9). Osteonecrosis can occur in the hips of patients with MED, thereby 670 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 56 Genetic Diseases and Skeletal Dysplasias complicating the radiographic appearance. Management Figure 10 Radiograph showing genu valgum in a patient with Ellis-van Creveld syn- in this circumstance is similar to the containment meth- drome. ods used for patients with Legg-Calvé-Perthes disease. Painful, stiff joints are managed by avoidance of activi- gum resulting from characteristic deficiency of the ante- ties that result in significant joint stress, administration rolateral tibial epiphyses (Figure 10). Realignment typi- of nonsteroidal anti-inflammatory drugs, and aquatic cally requires femoral and tibial osteotomies. and physical therapy. The typical genu valgum can be managed by staple hemiepiphysiodesis or osteotomy. Ellis-van Creveld syndrome has recently been linked Progressive osteoarthritis usually results in total joint ar- to a new gene named EVC, which encodes a protein throplasty. that has no homology to known proteins. It is expressed at higher levels in the distal limb than the proximal limb Three separate genetic loci have been linked to in human embryonic tissue, and it is also expressed in MED. As noted previously, mutations causing all clinical the developing vertebral bodies, ribs, heart, kidneys, and forms of MED have been identified in the gene encod- lungs. Although the structure of the EVC gene product ing COMP. The phenotype of the mild pseudoachondro- includes both putative nuclear localization signals and a plasia patients overlaps with those of MED. Other mu- transmembrane domain, its function is currently un- tations have been identified in COL9A2, which encodes known. the α 2 chain of type IX collagen. Type IX collagen is a nonfibrillar heterotrimeric molecule with three chains Dyschondrosteosis (Leri-Weill Syndrome) encoded by three different genes. It is a structural com- ponent of hyaline cartilage, intervertebral disks, and the Dyschondrosteosis (Leri-Weill syndrome) is a common vitreous body of the eye. Type IX collagen decorates the dominant disorder resulting in mild short stature, me- surface of type II collagen molecules to which it is co- somelic shortening, and Madelung’s deformity. The ra- valently cross-linked. Its function is postulated to in- diographic features are typical of Madelung’s deformity, volve mediating the interaction of type II collagen with with bowing of the radius and dorsal dislocation of the other extracellular matrix components in cartilage. ulna. Mutations in the short stature homeobox (SHOX) gene have recently been implicated as the cause of dys- The phenotype of the COL9A2 mutants seems to be chondrosteosis. Located at the very tip of the short arms milder without hip involvement compared with the of both sex chromosomes, the SHOX gene encodes a more severe disease caused by mutations in COMP. All mutations in COL9A2 described to date result in splic- ing errors that eliminate exon 3, and hence delete 12 amino acids from the N-terminal portion of the mole- cule. This may affect the structure and function of the molecule in mediating interactions between type II col- lagen molecules and other extracellular matrix compo- nents. Recently, an unclassified form of MED has been linked to COL9A3 in a four-generation family with au- tosomal dominant disease. This is the first disease- causing mutation to be identified in COL9A3, which en- codes another of the three α chains of type IX collagen. The phenotype of the COL9A3 mutants overlaps signif- icantly with COL9A2 mutants, but it differs by the pres- ence of hip involvement. Ellis-van Creveld Syndrome Ellis-van Creveld syndrome is an autosomal recessive disorder characterized by postaxial hand polydactyly, short stature with mesoacromelic shortening, sparse, thin hair, and dysplastic nails and teeth. Severe congeni- tal heart disease is seen in approximately 60% of chil- dren with this disorder. The diagnosis is typically made at birth. The radiographic features include the postaxial polydactyly, fusion of the capitate and hamate, and me- dial spikes projecting from the iliac bones. Children with Ellis-van Creveld syndrome develop severe genu val- American Academy of Orthopaedic Surgeons 671

Genetic Diseases and Skeletal Dysplasias Orthopaedic Knowledge Update 8 homeobox-containing DNA transcription factor. SHOX Diastrophic Dysplasia defects also appear to be associated with growth failure Diastrophic dysplasia is an autosomal recessive disorder in Turner’s syndrome, although it is not clear why fe- characterized by marked short stature and progressive male patients with Turner’s syndrome do not develop deformity. The diagnosis can be made prenatally by ul- dyschondrosteosis. trasound and by findings at birth, including a cleft pal- ate, tracheomalacia, hitchhiker thumbs, and bilateral Disorders Caused by Abnormalities in Genes equinocavovarus or skewfoot deformities. Cervical ky- Important in Normal Skeletal Development phosis is typically present in the perinatal period and in later childhood, joint contractures develop, and ky- This spectrum of disorders includes cleidocranial dysos- phoscoliosis is common. Cauliflower ear deformities re- tosis and nail-patella syndrome. sulting from cystic swelling in the cartilage of the ear commonly develop after birth. Cleidocranial Dysostosis Cleidocranial dysostosis is an autosomal dominant dis- Mutations in the diastrophic dysplasia sulfate trans- order with subtle clinical features consisting of a broad porter gene have been identified as causing diastrophic forehead, delayed closure of the anterior fontanel, in- dysplasia. The diastrophic dysplasia sulfate transporter creased ability to appose the shoulders, shortening of gene is ubiquitously expressed and encodes a protein the middle phalanges of the third through fifth fingers, that facilitates the transport of sulfate across the cell delayed eruption of the permanent dentition, and mild membrane. The disease primarily affects cartilage be- short stature. The diagnosis can be made at birth but is cause of the importance of negatively charged sulfate often delayed. Radiographic features include multiple groups in the function of proteoglycan molecules, which wormian bones in the skull, with delayed closure of the is to maintain the hydration and compressive strength of sutures and anterior fontanel. The clavicles are small cartilage. One in 70 Finnish citizens are carriers of a mu- and absent, and there is widening of the symphysis pu- tant diastrophic dysplasia sulfate transporter gene. bis. The disorder is caused by a mutation of core binding factor α1 (CBFA1). CBFA1 is a gene that is important Cervical kyphosis often resolves spontaneously. Pro- in the induction of osteoblast differentiation. The clini- gressive deformity and/or spinal cord compression re- cal features result in abnormal development of the ante- quires surgical management. Kyphoscoliosis can also oc- rior midline skeleton. Coxa vara can occur, and if symp- cur in the thoracolumbar spine; if progressive, it tomatic or progressive, it can be corrected with a typically requires anterior and posterior spinal fusion. proximal femoral osteotomy. Early hip development is normal, but most children with this disorder develop hip flexion contractures with Nail-Patella Syndrome epiphyseal irregularity. End stage osteoarthritis is man- Nail-patella syndrome or osteoonychodysplasia is an au- aged with total joint arthroplasty. Patients with di- tosomal dominant disorder characterized by aplasia or astrophic dysplasia often have flexion contractures of hypoplasia of the patellae and dysplastic nails, with the the knees, valgus alignment, and patellar dislocation. thumbnails being most commonly involved. Mutations Surgical realignment of the knees can be difficult in of the Lim homeobox transcription factor 1β (LMX1B) these patients. Congenital foot deformities include the gene cause this syndrome. LMX1B is involved in deter- equinocavovarus feet or skew feet. The traditional surgi- mining normal dorsoventral patterning in the develop- cal management results in rigid deformities with a high ing limb bud, and it is expressed in the eyes and kidneys. rate of recurrence, of which recurrent equinus is the Up to 30% of affected individuals develop renal failure most common. Supramalleolar osteotomies are often by the fourth decade of life. Glaucoma is another com- needed for realignment. plication associated with this disorder. The radiographic features include small or absent patellae and iliac horns. Mucopolysaccharidoses Posterior dislocation of the radial head limits elbow ex- The mucopolysaccharidoses consist of a large group of tension. Knee deformity and patellar malalignment may lysosomal storage diseases. Abnormal function of lyso- require soft-tissue releases and realignment osteoto- somal enzymes results in the intracellular accumulation mies. of partially degraded compounds. The mucopolysaccha- ridoses are subdivided by the enzymatic deficiency and Disorders Caused by Abnormalities in Genes That Play the accumulation of these partially degraded com- a Role in the Processing of Proteins pounds (Table 2). The subtypes are inherited in an auto- somal recessive manner, with the exception of Hunter’s This spectrum of disorders includes diastrophic dyspla- syndrome, which is a sex-linked recessive disorder. sia and a large group of lysosomal storage diseases called mucopolysaccharidoses. The clinical features vary depending on the severity of the subtype. Corneal clouding, deafness, hepatosple- nomegaly, and cardiovascular abnormality all are present in Hurler’s syndrome, and children with this dis- 672 American Academy of Orthopaedic Surgeons

Orthopaedic Knowledge Update 8 Chapter 56 Genetic Diseases and Skeletal Dysplasias Table 2 | Mucopolysaccharidoses Subtypes Subtype Cause Prognosis Type I H (Hurler’s syndrome) Alpha-L-iduronidase deficiency Type I H: Death in the first decade of life Type I HS (Hurler-Scheie syndrome) Type I HS: Death in third decade of life Type I S (Scheie’s syndrome) Sulpho-iduronate-sulphatase deficiency Type I S: Good survival Type II (Hunter’s syndrome) Multiple enzyme deficiency Death in second decade of life Type III (Sanfilippo’s syndrome) Type A (galactosamine-6-sulfate-sulphatase Death in second decade of life Type IV (Morquio’s syndrome) deficiency) More severe involvement in patients with type IV A Type B (beta-galactosidase deficiency) Type VI (Maroteaux-Lamy syndrome) Arylsulphatase B deficiency than in those with type IV B; survival into Type VII (Sly’s syndrome) Beta-glycuronidase deficiency adulthood is possible Poor survival with severe form Poor survival order usually die in the first decade of life. Morquio syn- Figure 11 Radiograph showing the presence of characteristic vertebral anterior drome, in contrast, has a much better prognosis, and beaking in a patient with Morquio syndrome. there is only mild corneal clouding with deafness, no hepatosplenomegaly, and only mild cardiovascular ab- ment can be achieved by osteotomies or staple hemiepi- normalities. Biochemical analysis of the urine can lead physiodesis in the growing child. to the diagnosis of the specific mucopolysaccharidoses. Specific enzyme activity known to be abnormal can be Bone marrow transplantation has been used success- detected in skin fibroblast culture and prenatally using fully to treat patients with Hurler’s syndrome and other chorion villous sampling. All of the subtypes lead to mucopolysaccharidoses. Although there has been im- short stature; patients with Morquio syndrome are the provement in the coarse facies and hepatosplenomegaly, most severely affected. Although there are common ra- the neurologic abnormalities and skeletal deformities diographic findings among this group of disorders, it is persist. Extensive research in the areas of gene therapy not possible to differentiate the various types based on and enzyme replacement is ongoing. radiographic features alone. The skull is enlarged with a thick calvarium. The ribs are broader anteriorly than posteriorly. The vertebral bodies are ovoid when imma- ture, but in time they develop platyspondyly. In patients with Morquio syndrome, an anterior beak develops at the thoracolumbar junction (Figure 11). Kyphoscoliosis is common. Epiphyseal ossification is delayed, and marked deformity of the joints can develop. The second through fifth metacarpals are narrowed at their proxi- mal ends and the phalanges are bullet-shaped. Atlantoaxial instability resulting from odontoid hy- poplasia and ligamentous laxity is very common, partic- ularly in patients with Morquio syndrome. Soft-tissue deposition in this area also results in further narrowing of the spinal canal. Children with this disorder must be very carefully evaluated for clinical signs of cervical my- elopathy and for any evidence of atlantoaxial instability. Treatment is by surgical stabilization of this area and decompression if required. Thoracolumbar kyphosis with anterior wedging is commonly seen in patients with Morquio’s syndrome. Bracing may be required; if it is progressive, anterior and posterior fusion is indicated. Severe hip deformity is common in this patient popula- tion, and proximal femoral and periacetabular osteoto- mies are typically used to realign the hip. Genu valgum can be secondary to distal femoral or proximal tibial valgus. If severe and interfering with function, realign- American Academy of Orthopaedic Surgeons 673