Limb loss and limb deficiency occur in significant numbers worldwide. Amputations are performed to remove limbs that are no longer functional because of injury or disease. The common reasons for amputation are related to diabetes, peripheral vascular disease, trauma, and malignancy. Genetic variation and mutation are the typical causes for congenital deficiencies. Upper limb loss is more commonly caused by trauma than lower limb loss. Before 1900, war-related injury was the major reason for limb loss in the United States. As America became industrialized, there was a rise in civilian trauma causing upper limb loss as a result of crush injury, laceration, and avulsion. A great deal is owed to our wounded military and manual laborers, then and now, for pushing the development of the technologies and options for those with limb loss today. The evolution of the upper limb prosthesis is founded on the principles of Salisbury and Newton. Prosthetic scientists stood on the shoulders of these giants while building functional tools that assist with performing daily tasks. As technologies advance, we are even more dependent on the training and the technical skill of the upper limb prosthetist. Despite entering the bionic age, the cable-and-hook systems remain the staple of upper limb prostheses because of their relative versatility and simplicity.
Demographics, Incidence, and Prevalence
In the United States an estimated 185,000 persons undergo an amputation of the upper or lower limb each year. In 2008, it was estimated that 1.9 million persons were living with limb loss in the United States (Johns Hopkins Bloomberg School of Public Health, unpublished data). Of this estimate, 500,000 persons were living with minor (fingers, hands) upper limb loss, and 41,000 persons were living with major upper limb amputations. Because of the aging of the population and higher rates of dysvascular disease related to diabetes and obesity, it is projected that the number of people living with lower limb loss in the United States will double by the year 2050.
Trauma accounts for 90% of all upper limb amputations. During the next 50 years, the incidence of amputations secondary to trauma is estimated to remain flat if not decrease. The incidence is hypothesized to decrease because of more successful occupational safety standards. The future is also likely to bring even more aggressive and successful limb reconstruction and replantation. Other causes of upper limb loss include burns, peripheral vascular disease, neurologic disorders, infections, malignancies, contracture, and congenital deformities.
Finger amputation represents the highest percentage (78%) of upper limb amputations reported on hospital discharges. Most amputations involve single digits, with the index, ring, and long fingers accounting for 75% and the thumb 16%. Excluding finger amputation, the most common upper limb amputations are through the forearm (transradial) and humerus (transhumeral), respectively ( Table 9-1 , Figure 9-1 ). Most civilian limb injuries that result in amputation occur at work and involve saws or blades (e.g., lawnmowers and snow blowers). Blast-related injuries are rare in the civilian population (8.5%). In the active military, however, amputee injuries are from mortars, gunfire, improvised explosive devices, and rocket-propelled grenades. Because of the extreme forces involved, concomitant injuries, such as traumatic brain injury, visual and hearing impairment, soft tissue loss, and burns, are common. A fifth of all combat-related major amputations involve the upper limb. Two thirds of amputations resulting from trauma occur among adolescents and adults younger than 45 years. Males account for greater than 75% of those with upper limb loss, and the more severe the injury, the more likely the victim is male.
Procedure | Percentage of Total Upper Limb Amputation Procedures Performed |
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Amputation through the hand | 15 |
Disarticulation through the wrist | 10 |
Amputation through the forearm (transradial) | 31 |
Disarticulation of the elbow | 7 |
Amputation through the humerus (transhumeral) | 28 |
Shoulder disarticulation | 7 |
Forequarter amputation | 2 |
An estimated 4.1 per 10,000 babies are born each year with all or part of a limb missing, ranging from a missing part of a finger to the absence of both arms and both legs. Congenital deficiencies in the upper limb are more common (58%), and they occur slightly more often in boys. The most common congenital amputation is at the left short transradial level. Most cases of congenital upper limb deficiency have no hereditary implications. Congenital limb deficiencies occur because of the failure of part or all of a limb bud to form. The first trimester is the critical time for limb formation. The bud appears at 26 days’ gestation, and differentiation progresses through the eighth week of gestation. The etiology often is unclear, but teratogenic agents (e.g., medications and radiation exposure) and amniotic band syndrome are two common causes. Maternal ultrasound examination often identifies the limb deficiency before delivery. There have been many descriptions of congenital limb deficiencies ( Box 9-1 ), with the development of the current and preferred system by the International Society for Prosthetic and Orthotics (ISPO; Box 9-2 ). The ISPO terminology divides the limb amputations into transverse or longitudinal. By definition, a child who has a transverse deficiency has no distal remaining parts. For example, a child with a transverse radial deficiency has a normal upper arm and a portion of the radius but is missing the hand and fingers. Longitudinal deficiencies have distal portions present with a partial or total absence of a specific bone. The most common congenital limb deficiency in the upper limb is a longitudinal partial or complete lack of the radius. Longitudinal hand reductions represent half of all congenital upper limb reductions, and multiple limb reductions are found in less than 20% of live births.
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Amelia: Absence of a limb
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Meromelia: Partial absence of a limb
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Phocomelia: Flipperlike appendage attached to the trunk
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Adactyly: Absent metacarpal or metatarsal
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Hemimelia: Absence of half a limb
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Acheiria: Missing hand or foot
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Aphalangia: Absent finger or toe
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Transverse deficiency: No remaining distal portions. Transverse level is named after the segment beyond which there is no skeletal portion.
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Longitudinal deficiency: Some remaining distal portions. Longitudinal deficiencies name the bones that are affected.
ISPO, International Society for Prosthetic and Orthotics.
Nomenclature and Functional Levels of Amputations
Radial amputations ( Figure 9-2, A ) involve the thumb and index finger and compromise grasp. Fingertip amputation ( Figure 9-2, B ) is the most common type of amputation. The thumb is the most functionally critical digit. Thumb amputation, partial or complete, results in loss of palmer grip, side-to-side pinch, and tip-to-tip pinch. Amputation of one of the other digits causes less functional loss. Transverse digit amputations occur at one or more digits and can be fit with functional finger prostheses. Ulnar amputations ( Figure 9-2, C ) involve digits IV and V with resultant loss of hook grasp. The loss of digit V is functionally underestimated because of this powerful grasp. Central amputation ( Figure 9-2, D ) involves digits III and IV, and reconstruction is usually not attempted. A cosmetic substitute is used instead. The residual limb refers to the remaining part of the amputated limb. The sound limb refers to the nonamputated limb. Wrist disarticulations are rare, but are preferred over more proximal amputations because maximal pronation and supination are preserved.
Proximal to the hand, amputations are divided into the following categories: transradial, elbow disarticulation, transhumeral, shoulder disarticulation, and forequarter amputation . Depending on the percentage of the limb remaining compared with the sound side, further categorizations can be made, such as “short” and “long,” to define the residual limb. These categorizations have functional implications. For the transradial residual limb, the longer the length, the more pronation (normal, 120 degrees) and supination (normal, 180 degrees) is preserved. Of the pronation and supination preserved, 50% can be transmitted to the prosthesis.
Transradial amputations are based on measurements made from the longest residual bone (ulna or radius) to the medial epicondyle. This is then compared with the measurement of the sound side from the ulnar styloid to the medial epicondyle. The remaining length impacts the ability to pronate and supinate the forearm with the prosthetic device. A long transradial amputation preserves 55% to 90% length, allows up to 60 degrees of supination and pronation with a prosthesis, and maintains strong elbow flexion. A medium transradial amputation preserves 35% to 55% length, but pronation and supination with a prosthesis are lost. Elbow flexion is reduced because of the inhibiting prosthesis. A short transradial amputation is defined as 0% to 35% preservation, which results in difficult prosthetic suspension and the additional loss of full range of motion (ROM) at the elbow.
Elbow disarticulation creates functional and prosthetic fit difficulties related to suspension and elbow joint placement. This level of amputation preserves humeral rotation of the prosthesis and can be accommodated by modern socket fabrication techniques and cosmesis. It is most suitable for the growing child to preserve the epiphysis for growth. Elbow disarticulation is recommended instead of bilateral transhumeral because of functional prosthetic control.
The transhumeral amputation can also be classified into three levels. The more humeral length preserved, the more optimal the prosthetic restoration. The long transhumeral is defined as preservation of 50% to 90% of length relative to the sound side. Glenohumeral motions are preserved and uninhibited by the prosthetic socket. The short transhumeral is defined as preservation of 30% to 50% of length, which results in loss of glenohumeral motion because of the inhibition of the prosthetic socket that encompasses the acromion. The glenohumeral motions of flexion, extension, and abduction are lost with humeral neck level amputation, shoulder disarticulation, and forequarter amputation . They are usually amputations related to malignancy and severe trauma in which no distal level amputation was possible. These levels of amputation present challenges to achieving adequate suspension and functional use of the prosthesis. Newer myoelectric techniques are gaining ground in achieving the multijoint control that is needed in optimal prosthetic restoration for these very proximal upper limb amputations.
Principles of Limb Salvage and Amputation Surgery
Limb Salvage
Limb-sparing procedures have become possible because of advances in imaging, reconstructive surgery, microsurgery, and cancer treatment. Improved methods of resuscitation and time-sensitive transport have decreased ischemia time. Optimal skin and soft tissue closure with pedicle flaps and microvascular free flaps allows the surgeon to meet the initial goal of critical limb length and the later goal of skin durability for long-term socket use. Whether it is tumor, trauma, or congenital malformation, the decision to attempt salvage with reconstruction or amputation remains difficult. The best decision is one formed by the consensus of the experienced trauma, oncology, and rehabilitation specialists. Upper and lower limb characteristics are different and must be kept in mind when considering limb salvage or amputation. The upper limb is non–weight bearing. It remains functional with significant sensory impairment, which is different from the lower limb. An upper limb that preserves only assistive function is still often more functional than one with a prosthetic replacement.
Injury scores were developed for severe trauma-related limb injuries, to help determine which vascular injury patients would benefit from primary amputation versus an attempt at limb salvage. Their validity has been questioned. The mangled extremity syndrome is defined as significant injury to at least three of the four tissue groups (skin/soft tissue, nerve, vessel, and bone). The mangled extremity scoring systems have been shown to be poor predictors of amputation or salvage with regard to functional outcome. Ly et al. concluded that the available injury severity scores are not predictive of functional recovery of patients who undergo reconstruction surgery. Bosse et al., using the Sickness Impact Profile , presented evidence that the functional outcomes from limb salvage and reconstruction after severe trauma were the same at 2 years for those who underwent amputation. Finally, in this salvage-versus-amputation equation, no significant long-term psychological outcome advantage has been reported for limb salvage surgery compared with amputation. Consequently, objective measures have not functionally supported the natural desires of the patient and the tendency of the trauma team to make all attempts at salvaging the limb.
In severe limb trauma that includes defects from burns and tumor resection, the appropriate soft tissue restoration is an essential component of the overall treatment. This is common both to limb salvage and amputation, especially when critical lengths are being preserved. It requires a vascularized flap that can protect the neurovascular and musculotendinous structures ( Box 9-3 ). The pedicle flap is a local muscle inclusive of the overlying skin that is moved over with its own blood supply to fill a large defect. A microvascular free flap is one in which the donor tissue is taken from a different site and the microvasculature of the donor tissue is anastomosed to the available vessels in the site of the defect. The feasibility of limb salvage is determined partly by the ability to reconstruct the soft tissue defect. In the upper limb, few pedicle flap options are available to repair significant defects. The recent advancement of microvascular reconstruction techniques and free flaps from sites like the rectus abdominis have expanded the option of limb salvage and preserved limb length.
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Pedicle flap: A flap in which a local muscle inclusive of the overlying skin is moved over with its own blood supply to fill a large defect.
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Microvascular free flap: A flap in which the donor is not local and the microvasculature of the donor muscle is anastomosed to the available vessels at the defect site.
Once it has been decided that amputation is more appropriate than limb salvage, the team must determine the most distal level possible, based on principles of wound healing and functional prosthetic fitting. Skin flaps now afford closures that were not historically possible. The skin closure must be without tension and should be done so that nonadherent, strategically placed, mobile scars are produced. It is the artful surgeon who crafts the distal residual limb with the appropriate muscle padding, rather than producing a bony atrophic limb or one with excessive preservation of soft, redundant tissue that makes it difficult to fit the prosthetic socket. Stable distal muscle padding can be accomplished through myodesis, in which the deep layers are sutured directly to the periosteum. It can also be accomplished by myoplasty, in which the superficial antagonistic muscles are sutured together and to the deeper muscle layers. These techniques typically produce muscle padding with sufficient balance and tension.
Although these are the conventional surgical techniques to address the residual muscle tissue, myoplasty presents a challenge later when attempting to localize an optimal myoelectrode placement. Because the muscles are sutured together, they tend to contract simultaneously. The ideal distal muscle stabilization occurs with tenodesis . If the muscle is preserved with its tendon, the tendon can be sutured to the periosteum.
Neuroma formation is the normal and expected consequence of nerve division. Nerves should be gently withdrawn from the wound, sharply divided, and allowed to retract under cover of soft tissue. The goal is to locate the ends of incised nerves away from areas of external contact, such as the socket interface, so the cicatrix will remain asymptomatic.
For those with malignant tumors, 70% to 85% are treated by limb salvage without compromising the oncologic result. The goal of this type of surgery is to preserve function, prevent tumor recurrence, and enable the rapid administration of chemotherapy or radiation therapy. For tumors of the hand, ray resection is done. In the wrist, multiple options are available such as an endoprosthesis implant or an allograft or vascularized bone transplant (e.g., fibula). For the elbow, an endoprosthetic reconstruction is the best possible option. The humerus is similar to the wrist in that an endoprosthesis, or an allograft, or a vascularized bone transplant can be used. For tumors of the scapula or proximal humerus, a forequarter amputation or flail arm is prevented by reconstruction with a combination of an endoprosthesis and allograft. These types of reconstruction would not be possible without major improvements in radiography, chemotherapy, radiotherapy, and staging.
The complication rate is much higher after limb salvage than after amputation in the oncology population. These complications can be divided into early and late. The earliest complications include infection, wound necrosis, and neurapraxia. The late complications include aseptic loosening, prosthetic fracture and dislocation, and graft nonunion. Consequently, additional surgery is often necessary. Advancements in resection techniques, radiation, and chemotherapy have improved both functional limb survival and life expectancy. Serletti et al., using the Enneking Outcome Measurement Scale , reported the functional outcome as “excellent” or “good” in more than 70% of the patients who had reconstruction after resection of limb sarcomas. The Enneking Outcome Measurement Scale is an outcome tool that assesses seven characteristics of upper limb use: ROM, stability, deformity, pain level, strength, functional activity, and emotional acceptance. Limb salvage has cosmetic advantages, but whether the quality of life of these patients is superior to that of those who undergo amputation is unclear.
Hand Replantation
Hand replantation (HR) of traumatically amputated limbs is now possible, especially in children, because of the potential for successful neurologic recovery. Effective treatment of the patient and the ischemic, detached body part requires appropriate early cooling and prompt replantation within the initial 12-hour window. The success of digital replantation is well documented, whereas successful hand and distal forearm replantation is less common. The decision to replant is based on evidence that the function and overall well-being of the patient will be better than with a prosthetic device. All indications for replantation must take into account the patient’s general health, the ischemia time and the level, type and extent of tissue damage. It requires prolonged recovery periods, multiple procedures, and motivated patients to achieve optimal outcomes. Predictors of successful replantation include adequate preservation, contraction of the muscle in the amputated limb after stimulation, the level of injury, and no tobacco use. The best predictor of success is the serum potassium level in the amputated segment. If the serum potassium level is higher than 6.5 mmol/L, replantation should be avoided.
Replantation is indicated in levels from the distal forearm to the fingers. The more proximal to the wrist, the greater the amount of ischemic muscle mass and the more complex the metabolic and surgical demands. Approximately 85% of replanted parts remain viable. Sensory recovery with two-point discrimination occurs in 50% of adults. The functional results are more promising in children, but the viability rate is lower because of the technically demanding microvascular surgery. Major limb replantation entails significant metabolic disturbance and risk. It requires scrupulous medical management. Replantation is contraindicated in those with crushed and mangled limbs and those with atherosclerosis. Because nerves transected in the proximal arm must regenerate over a considerable length, only limited motor return is typically seen in the forearm and hand, particularly the intrinsic muscles of the hand. Useful function of the wrist and hand is unusual and limited at best. Function can often be improved by converting these patients to transradial prosthetic wearers. Unfortunately, it means performing a transradial amputation after successful transhumeral replantation. This is known as segmental replantation, in which portions of compromised limbs are salvaged that would otherwise have been discarded.
The steps in replantation surgery are given in Box 9-4 .
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Open reduction and internal fixation of the ulna (with six-hole plate) and radius (with eight-hole plate).
- 2.
This was followed by repair of all injured tendons: flexor digitorum profundus (FDP) 2-5, flexor digitorum superficialis (FDS) 2-5, flexor pollicis longus, flexor carpi radialis, flexor carpi ulnaris, palmaris longus, extensor carpi ulnaris, extensor digitorum 2-5, extensor digiti minimi, extensor pollicis longus and brevis, abductor pollicis longus, extensor carpi radialis longus and brevis.
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The radial and ulnar arteries were repaired.
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Repair of the median, ulnar, radial, and dorsal ulnar sensory nerves.
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The basilar vein was repaired, and a 3-cm vein graft repair was made of the cephalic vein.
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Closure was achieved with advance of skin flap and the use of a skin graft.
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Total tourniquet time of the surgery was 2 hours and 45 minutes.
Hand Transplantation
During the past 15 years, collaboration between hand surgeons and immunologists has led to successes in hand transplantation (HT). Advances learned from clinical organ transplant immunosuppression known as composite tissue allograft (CTA) have permitted HT to progress beyond the first operation in the United States in 1997. CTA is the term used to describe transplantation of multiple tissues (skin, muscle, bone, cartilage, nerve, tendon, blood vessels) as a functional unit. The first long-term success was when a team in Louisville, Kentucky performed a transplant on a 24-year-old man who had lost his hand in a firework accident. The Louisville patient is still alive, enjoying a restoration of function and appearance once deemed impossible. Since then, more than 65 hand and upper limb transplantations have been performed around the globe, in the era of immunosuppression. The ultimate goal of HT is to achieve graft survival and useful long-term function. For these goals to be achieved, selection of the appropriate patient, detailed preoperative planning, and precise surgical technique are of paramount importance. Transplantation should be reserved for motivated, consenting adults in good general heath, who are psychologically stable and have failed a trial of prosthetic use.
Although HR and HT are similar with regard to the surgical procedure, differences can exist ( Table 9-2 ) starting with the most obvious: selecting a donor for a HT must involve additional and careful emphasis on matching skin color, skin tone, gender, ethnicity and race, and the size of the hand. Next is a difference in operative sequence. As for HR, the operative sequence of HT varies based on the amount of muscle transplanted. Distal transplantations (distal to the distal one third of the radius) have relatively less muscle mass than more proximal level HTs. The more distal HTs can tolerate a longer period of ischemia. Thus, some groups have delayed the revascularization to later in the surgical sequence. Proximal forearm transplantations, with the concomitant increased muscle bulk, require rapid revascularization to avoid ischemic injury and prevent muscle fibrosis. Ischemia time is one of the main factors influencing the outcome after HT because total ischemia time is often 1.5 to 3 times longer than replantation. Other differences include the fact that HRs are often performed by a single microsurgeon in contrast to HT logistics, which require two surgical teams: the harvesting team and the transplant team, working in tandem against the clock. In HT, the allograft is harvested according to the specific anatomic needs in the recipient; various structures must be dissected with excess length to facilitate reconstruction and allow vascular and nervous repairs without tension. With HR there is a paucity of tissue, and efforts are made to conserve tissue. Limited bone shortening is done to alleviate tension on the neurovascular and tendon repairs. However, the relative tension and balance between the flexor and extensor tendons is generally left intact. With HT, an excess of tissue is available and one must judge exactly what is needed to suit the recipient’s unique requirements. As a result, the relative tension between the flexor and extensor tendons must be reestablished. Barring major traumatic bone loss, forearm length is generally preserved with HR. With HT, the appropriate forearm length must be reconstructed to match the contralateral side. The HT surgery can last from 12 to 16 hours, almost double that of heart and liver transplants. Immunosuppression after CTA is composed of two elements: (1) treatment of the patient with monoclonal antibodies on the day of transplant, followed by (2) a donor bone marrow infusion several days later. Typical postoperative complications include vessel thrombosis, infections, and rejection. Rejection can appear as a spotty, patchy, or blotchy rash. It could appear anywhere on the transplant and is usually painless. As rejection appears first in the skin, the clinical team and patients are encouraged to carefully watch for the signs. Unlike internal organ transplants, rejection is easier to detect early.
Hand Transplantation | Hand Replantation | |
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Surgery | Planned and performed electively | Emergency surgery |
Donor tissues | Intact | Missing, avulsed, crushed, or contaminated |
Modification of donor graft | Tailored to match specific requirements | Limited by type of injury |
Recipient site | May be scarred with muscle contracture and reduced tendon excursion | Missing, avulsed, crushed, or contaminated |
Warm ischemia time | Minutes | Minutes to hours |
Immunosuppression | Long-term antirejection drugs needed | Not necessary |
Rehabilitation After Hand Replantation and Hand Transplantation
Rehabilitation after HR focuses on mobilization of the replanted hand through conventional hand rehabilitation ( Box 9-5 ). Exercises maintain optimal length of ligament and joint capsular structure of the metatarsophalangeal (MP) joints, balancing the tension between flexors and extensors, and, at the same time preventing edema formation in finger joints. After a hand has been lost, much time can pass before a donor is found. Representation of the hand in the individual’s brain is lost because of cortical reorganization during this time. Researchers have learned through functional magnetic resonance imaging that after transplantation, amputation-induced cortical reorganization is reversed to reestablish the hand “image.” Thus, rehabilitation after HT involves cortical reprogramming and reintegration of the transplanted limb, in addition to conventional hand rehabilitation. A rehabilitation protocol should focus on dynamic orthotic intervention, active/passive exercises to improve ROM, grip strengthening, and sensory reeducation over the first year of therapy. Supportive surgeries, interrupting the episodes of therapy, are often needed to treat problems of bone nonunion, tendon transfer, and excessive scar tissue development affecting neural and muscle tissue. Recovery is relatively slow, requiring an extensive program of occupational therapy episodically, for years.
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Proper hand positioning: wrist extension (15 degrees to 30 degrees) protects extensors for as long as needed to prevent any lag while hand is in intrinsic plus/thumb abducted palmarly and radially.
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Prevent clawing: do not allow full metatarsophalangeal extension until intrinsics have recovered enough function.
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Control edema: elevation and gentle soft tissue massage; no compression.
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Exercises: early tendon gliding exercises and range of motion.
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Cognitive exercise training with electrostimulation (Perfetti protocol).
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Electromyographic biofeedback training.
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Patient and family education and training of all exercises and orthotic wear.
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Control pain: pain medications (neuropathic), gentle early mobility, and modalities.
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Educate about protection because of sensory precautions.
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Keep limb warm, avoid smoking, caffeine, and cold for at least 3 to 4 weeks.
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Begin dominance retraining when appropriate.
Outcomes
The more proximal level of limb amputation, the lower the chances of regaining satisfactory hand function after transplantation. The major challenge in HT is the long distance between the nerve stumps and their end organs. Experience in “forearm” transplantation suggests that motor function may continue to improve during 5 or more years after transplantation. One of the main hurdles limiting the efficacy of hand rehabilitation is the cortical organization shift that occurs after sensory and motor deprivation in amputees. There is a superiority of reinnervation in HT, including good sensitivity as well as a two-point discrimination. The favorable outcome with regard to nerve regeneration may be related to possible neuroregenerative properties of tacrolimus, which promotes nerve growth in vitro, enhancing regeneration in various peripheral nerve injury models. The functional results achieved after unilateral and bilateral HT worldwide showed that all patients had protective sensitivity, 90% of the recipients had tactile sensitivity, and 84% also had discriminative sensation. Many patients have returned to work. The quality of life scores have improved in 75% of patients after transplant. Patient satisfaction seems to be greater after HT. This may be related to the observation that patients with HT constitute a selected group of highly compliant patients who are well prepared for the surgical procedure and rehabilitation. Their expectations might therefore be more realistic.
In HR, the innervation of intrinsic hand muscles, responsible for precise movements, is limited. A claw hand deformity can occur because of poor positioning and limited and slow nerve regeneration, specifically secondary to decreased ulnar nerve innervations to the intrinsic musculature. This results in functional limitations consisting of poor opposition of the thumb due to lack of innervations to the thenar muscles, diminished fine motor abilities, and lack of sensibility due to lack of ulnar nerve innervation. Traumatic amputations of the hand often result in large cortical areas of the brain being deafferented, which is followed by extensive cortical reorganization so that the adjacent and contralateral cortical areas take over the function of the vacant area. After replantation of the hand, functional return can only occur after the peripheral sensory nerves reclaim their original cortical territory. Thus, after HR, studies have used functional magnetic resonance imaging to map the activation pattern of the motor cortex. Recovery of normal activation pattern varies between patients, but a general consensus of 6 weeks for normal activation pattern is seen. Most patients after HR have fairly good motor function return, although sensory recovery is poor. In addition, they often have severe cold intolerance. It is unclear why these individuals have such an extensive loss of functional sensory recovery. Grip strength was superior after HR, even in cases with extensive bony shortening. In HR, the severely impaired muscles seem to have greater potential for recovery when compared with inactivated, fibrotic, and atrophic muscles of a HT recipient’s stump. Patients undergoing HR are a random group of people undergoing emergency surgery compared with those receiving HT and expect their replanted hand to function as well as before the amputation.
Amputation
Hand function is vital in our competitive and industrialized society. There are many techniques for reconstruction of the hand. It is much better to have a painless hand with some grasp function and sensation preserved than to have a prosthesis. The most important part of the hand is the opposable thumb. The goal is to preserve as much of the sensate thumb as possible. Phalangization of the metacarpals is a reconstructive technique in which the web space is deepened between the digits to provide more mobile digits ( Figure 9-3 ). This works well for the thumb, especially if the first metacarpal is adjusted to create opposition to the thumb. Pollicization is the process of moving a finger with its nerve and blood supply to the site of the amputated thumb ( Figure 9-4 ). This allows fine and gross grasp through opposition. A prosthesis for a hand amputation is inferior to the functional outcomes achieved with reconstructed hands. In reconstructing the hand, three issues should be considered: (1) preservation of sensitivity to the grasping surface; (2) the consequences of scarring; and (3) cosmetic acceptability.
Wrist disarticulation involves removal of the radius and ulna to the styloid processes, because there is no benefit to retaining the carpal bones. It retains the distal radial-ulnar joint, preserving more forearm rotation. The prosthetic attachment to the bulbous end is enhanced if the distal radial flare is retained for suspension. Burkhalter et al. indicate that it is important that the radial and ulnar styloids be resected slightly to minimize the discomfort the amputee will experience in active supination and pronation within the prosthetic socket. Tenodesis of the major forearm muscles stabilizes these groups and improves functional outcome, including myoelectric performance. Pronation and supination, as well as full elbow motion, are preserved with wrist disarticulation. Some will argue that (1) the wrist disarticulation creates a complicated prosthetic situation with difficult socket fabrication; (2) conventional wrist units are too long and cannot be used; and (3) it is harder to fit with a myoelectric prosthesis because there is no room to conceal the electronics and power supply.
Transradial amputation involves the myodesis of the forearm muscles and equal volar and dorsal skin flaps for closure. It is extremely functional, with forearm rotation and strength that is proportional to the length retained. The shorter the transradial amputation, the more the elbow and humerus are needed for suspension. Preserving the elbow joint is paramount because of the functional outcome possible with prosthetic enhancement. If the amputation must be very proximal, then an ulna 1.5 to 2 inches long is still adequate to preserve the elbow joint. For this very short residual limb to be fit with a prosthesis, it might be helpful to detach the biceps and reattach it to the ulna.
A couple of special situations arise with transradial amputations. First, when one forearm bone is considerably longer than the other and the longer bone can be covered with an adequate soft tissue envelope, it may be preferable to create a one-bone forearm rather than decrease prosthetic function by shortening the longer bone. Second is the Krukenberg amputation, which transforms the residual ulna and radius into digits that have significant forceful prehension and retained ability to manipulate because of preserved sensation ( Figure 9-5 ). This is an option for patients with at least 4 inches of residual limb, those with bilateral amputation, and those with limited prosthetic facilities. It can be fitted with conventional as well as myoelectric prostheses.
Elbow disarticulation allows the transfer of humeral rotation to the prosthesis, through the myodesis of the biceps and triceps, and it preserves a stronger lever. Although the skin flaps are approximately equal, the posterior muscle flap remains longer than the anterior muscle flap, to wrap around and cushion the end of the humerus. With modern total-contact sockets, the ultimate position of the scar is not critical; however, clinicians should be aware of the vulnerable skin over the medial epicondyle. The full humeral length precludes the use of a myoelectric elbow. Elbow disarticulation causes some prosthetic fitting challenges because the outside “elbow” hinge creates a bulky limb that is longer and asymmetric compared with the opposite limb. Disarticulation is the level of choice for juvenile amputees. The high incidence of residual limb revision because of bony overgrowth is avoided and humeral growth is preserved. It remains controversial who is a good candidate for elbow disarticulation, but modern prosthetic fabrication techniques can overcome the socket and cosmetic difficulties.
Transhumeral amputations are performed at or proximal to the supracondylar level. The humerus is sectioned at least 3 cm from the joint to allow for fit of the prosthetic elbow mechanism. Transhumeral amputations should be performed with minimal periosteal stripping to prevent the occurrence of bony spurs. Rough edges should be removed, but beveling of the bone is unnecessary. All possible length should be preserved to transmit glenohumeral motions through the prosthesis. To help preserve humeral length, free flap coverage and skin graft coverage should be considered as possible alternatives for primary closure. The anterior fascia and posterior fascia over the flexor and extensor muscle groups are sutured together to cover the end of the humerus. Biceps and triceps myoplasty preserves strength for prosthetic control and myoelectric signals. Myodesis is rarely needed. Performing a more proximal amputation at the level of the surgical neck, which is the site of insertion of the pectoralis major, results in the same function as if a shoulder disarticulation had been done. This is because independent motion of the humerus is no longer possible. However, because the terminal device is controlled by active shoulder girdle motion, the humeral head should be preserved when amputation has to be done proximally.
Amputations through the glenohumeral and scapulothoracic articulations, shoulder disarticulation and forequarter amputation, respectively, are rare, and both result in loss of normal shoulder contour. Advances in vascular surgery have made reestablishment of blood flow to severely traumatized limbs effective, but replantation of a limb amputated through the shoulder girdle is seldom feasible. The cosmetic deformity of both of these amputations is significant. When possible, retention of the scapula is far less disfiguring and is of psychological benefit to the patient. Personal concerns of having standard clothing fit supersede more complex concerns of functional restoration. In shoulder disarticulation, the rotator cuff tendons should be sutured together over the glenoid wing. The deltoid is attached to the inferior glenoid and lateral scapular border to fill the subacromial space. In forequarter amputation, the pectoralis major, latissimus dorsi, and trapezius are sutured together to form additional padding and contour over the chest wall. During forequarter amputation, osteotomy of the clavicle should be performed at the lateral margin of the sternocleidomastoid insertion to preserve contour of the neck.
Acute Management: Preamputation Through Early Rehabilitation
Preamputation
The team approach to amputee rehabilitation begins in the preamputation phase whenever possible. The surgical team joins forces with the rehabilitation team to educate and counsel each other and the patient. It is important to include family members and other supporting individuals in the counseling. A plan of the surgery must be made that takes into account an understanding of the healing potential and the most realistic and optimal functional prosthetic restoration. This is based on the information flow between the rehabilitation team and the surgical team. Important discussions need to be held with the patient about the planned surgical outcome and postsurgical period. This should include a discussion about the different types of pain that might occur, the prevention of possible complications, and a preview of potential functional outcome. It is important to acknowledge the loss and mitigate the fear with education. A powerful intervention is to have a trained amputee volunteer, a “peer visitor,” who has successfully gone through a similar limb loss and can give support to the patient throughout the recovery process.
Acute Postamputation
This phase begins with an understanding that the decision to amputate is emotionally powerful for the patient, family, and clinical team. Amputation is not a failure but rather reconstructive surgery that creates improved functional possibilities and resumption of one’s life. The focus of the immediate postamputation period is to control pain and edema, promote wound healing, prevent contractures, initiate remobilization, and continue the supportive counseling and education ( Box 9-6 ). This must be individualized to meet the needs of each patient. Surgical site infection needs to be seriously considered when pain, drainage, and edema are increasing despite the reasonable control measures instituted. The earlier an infection is eradicated, the earlier the time-sensitive prosthetic phase can begin. The goal for rehabilitation is for patients to acquire the skills and equipment needed to achieve prosthetic acceptance and holistic reintegration back into their own lives. It is imperative that the prosthesis be introduced at the earliest possible time after amputation.
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Promote wound healing
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Control pain
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Control edema
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Prevent contracture
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Initiate remobilization and preprosthetic training
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Manage expectations through supportive counseling
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Continue education, including orientation to prosthetic components
The team has a responsibility to explain and give visualization of the postamputation treatment phases, from the early postoperative phase through rehabilitation and community reentry. Each team member (including the surgeon, physiatrist, prosthetist, and rehabilitation therapist) has specific duties related to physical, educational, and psychological support through these phases. An amputee peer visitor, preferably someone who has been formally trained, is a team member who has a unique perspective because of real-life experience. The Amputee Coalition of America (ACA), which is the national nonprofit limb loss advocacy group in the United States, can serve as a comprehensive source of information to persons with limb loss and their professional team. This includes locating ACA-trained peer visitors and regional support groups.
Pain control requires an early, aggressive approach that considers the multiple potential pain generators in the postsurgical period. The patient-controlled analgesia systems are often the first-line treatment by the surgical team. This is transitioned to regularly scheduled long- and short-acting oral narcotic medications. It is imperative to maintain consistent pain control. Loss of adequate pain control is painful for the patient and disrupts the timely pursuit of the rehabilitation program. The escalation of the doses of opiates needs to be avoided, if possible, by addressing other pain generators. Understanding the characteristics of postsurgical residual limb pain and phantom pain allows the clinical team to choose pain interventions wisely. Residual limb pain is located in the remaining limb and generated from the soft tissue and musculoskeletal components. Phantom limb pain is pain in the absent limb and is considered neuropathic. Nonsteroidal antiinflammatory drugs and nonopiate pain relievers are helpful and can diminish the need for higher doses of opiates. Opiates administered at safe doses are often ineffective against phantom pain. Careful attention should be given to the description, timing, and quality of the pain complaint to tease out the central neuropathic pain component inclusive of painful phantom sensations versus peripheral nerve-generated pain. Peripheral nerve pain is more intense at night and is characterized as burning, stabbing, and buzzing. Phantom sensations occur in more than 70% of amputees and do not have to be treated unless painful and disruptive. The use of medications known for controlling neuropathic pain and sensations, such as some anticonvulsants and antidepressants, can also diminish the need for opiates.
The new amputee should be taught how to change the dressings and use desensitization techniques. Desensitization techniques help to eliminate the hypersensitivity to touch. They include compression, tapping, massage, and application of different textures. These techniques are performed for 20 to 30 minutes 3 times per day as tolerated by the skin and scar. The use of modalities, such as transcutaneous nerve stimulation, heat, and cold, are also useful adjuvants for pain control and diminish opiate need. Ramachandran and Rogers-Ramachandran have reduced phantom pain using mirrors to visually trick the brain. Because the loss of a limb is emotionally “painful,” the team should address and acknowledge this. It should be kept in mind that from the individual’s psychological standpoint, it might be more socially acceptable to express the psychological pain in terms of generalized pain complaints. It is important to address the psychological pain early through grief counseling, peer visitation, and education.
Edema control begins once the last suture or staple is placed by the surgeon. If there is no contraindication and the surgeon has the appropriate training, an immediate postoperative rigid dressing (IPORD) can be placed in the operating room. This is a special cast placed on the residual limb by the surgeon or certified professional. The control of edema leads to earlier wound healing and improved pain control through the reduction of pain mediators in the accumulated “third-spaced fluid.” Typically, additional shrinkage of the residual limb occurs after the initial IPORD placement, necessitating its early replacement. The rigid dressing can be removed in 5 to 7 days and replaced with a fresh cast. The attachment of joints and a terminal device to this rigid dressing creates an immediate postoperative prosthesis that can allow early functional use of the residual limb. The IPORD is the preferred treatment approach for the transradial amputation, and if healing progresses without issue, the second cast can be replaced with the first prosthesis.
Traumatic upper limb loss is often accompanied by large tissue defects, burns, and wound contamination from complex infections. These make immediate postoperative techniques impossible. In these cases, once drains and negative pressure dressings are discontinued, a soft compressive dressing can be placed to control edema and initiate shaping of the residual limb.
The ideal residual limb shape is cylindrical. The dressing should be placed and replaced by a trained clinician. It should extend beyond the proximal joint to maximize suspension and improve edema control. Those not placed correctly can create problems with distal edema accumulation, skin breakdown, and abnormal shaping (such as a dumbbell shape). The healing surgical and trauma sites frequently have patches of sensory impairment and should be monitored by the team to prevent the development of pressure sores. Once the skin has closed, dressings are replaced with “shrinkers,” a silicone liner, or both. Edema control is a lifelong daily management issue for most amputees.
The control of pain and residual limb edema allows for early functional remobilization of the residual limb, which in turn helps prevent contracture formation . Contractures are not fully reversible, and it is critical to begin remobilization as early as possible. Techniques for prevention of elbow flexion and shoulder adduction contractures should be reinforced with the patient and team. This can be difficult in the setting of uncontrolled pain, burns, and other complex trauma factors, such as fractures, brain or spinal cord injuries, spasticity, and systemic illness.
The formation of heterotopic bone impairing joint function and ROM should be considered in these complex trauma cases and can be diagnosed with the help of laboratory testing and triple-phase bone scan. The treatment of heterotopic ossification beyond trying to maintain ROM and nonsteroidal antiinflammatory drugs is limited. Surgical intervention is not feasible until the heterotopic bone matures at approximately 12 to 18 months after injury. Proper limb positioning and frequent monitoring of joint mobility are necessary. Any loss of ROM in a joint of the residual limb can have significant effects on functional use of the prosthesis. The loss of ROM needs to be investigated and aggressively managed to maximize range.
Preprosthetic training begins with the early postsurgical therapy visit and continues until prosthetic fitting is completed. Prosthetic fabrication and fitting ideally should be completed within 4 to 8 weeks after surgery. Early prosthetic fitting is important, because prosthetic acceptance declines if fitting is delayed beyond the third postoperative month. Preprosthetic training is critical to maintain motivation and create an easier transition to prosthetic use. Amputation results in a loss of body symmetry. This imbalance results in shoulder elevation and scapula rotation on the affected side, as well as loss of neutral positioning of the residual limb. Close attention must be paid to the individual’s awkward or compensatory body motions when approaching an object. The rebalancing begins with observing and correcting static postures in the mirror. The mirror remains an important tool in conscious recognition and correction of the abnormal positioning. The amputee is encouraged to use muscle memory to relearn correct postural and limb positioning control. As remobilization progresses, emphasis is placed on recognizing the abnormal postures and positioning that occur with basic activities of daily living (ADLs).
ADLs are mastered with one hand and, when appropriate, with the use of adaptive equipment. The amputee progresses from independence with basic hygiene to advanced homemaking tasks. Hand dominance is retrained when necessary, especially with handwriting and keyboarding. Repetitive tasks can be used for strengthening. These tasks include fine motor exercises with nuts and bolts or tweezers, as well as gross motor exercises with equipment and mirrors. Proprioceptive neuromuscular facilitation is a particularly effective approach that enables the therapist to work in diagonal planes, vary the amount of resistance, and concentrate on specific areas of weakness. Isometric exercises are effective in creating muscle bulk for stabilization of the arm in the socket of the prosthesis. The stability of the prosthesis depends on both the bulk of the stabilizing musculature and the amputee’s ability to voluntarily vary residual limb configuration. Because balance is often disrupted in a new amputee, the goals should include strengthening of the trunk, core, and lower limbs using isometric exercise and aerobic training. Depending on the level of loss, the upper limb amputee should begin to practice several motions that will be needed to control the prosthesis ( Box 9-7 ).