Definition

Upper limb amputations are devastating occurrences for individuals, with profound functional and vocational consequences. In the United States, overall, there are approximately 1.7 million people living with a limb loss, or approximately 1 of every 200 people [1]. In contrast to lower limb loss, upper extremity amputation is much less frequent, affecting approximately 41,000 persons, or about 3% of the U.S. amputee population [2]. The primary reason for upper limb loss is trauma; cancer is the next most common reason [2–4]. The rates for traumatic amputations declined by 50% during the period 1988 to 1996 [3], probably because of changing work force patterns and greater concerns for industrial safety. However, as a result of the recent wars in Afghanistan and Iraq, the number of catastrophic injuries due to explosive devices has increased [5]. Traumatic amputation is the major reason for upper extremity loss in the military [5]. As of September 2010, 21% of major limb loss sustained in Operation New Dawn, Operation Iraqi Freedom, and Operation Enduring Freedom involved the upper extremity [5,6]. As of September 2010, there were 1219 major limb and 399 partial limb amputations [6].

Upper limb amputations from trauma occur at a rate of 3.8 individuals per 100,000; finger amputations are the most common (2.8 per 100,000). Hand amputations from trauma occur at a rate of 0.02 per 100,000 [3]. Traumatic transradial amputations occur at a rate of 0.16 per 100,000 persons, and transhumeral limb loss from trauma occurs at a rate of 0.1 per 100,000 [3].

Limb amputations that result from malignant neoplasms have declined approximately 42% from 1988 to 1996 [3]. Their rates of occurrence are lower than for trauma, with an upper limb loss rate in 1996 of 0.09 per 100,000 [3]. These rates of upper limb amputations are lower than the incidence rates of lower limb dysvascular amputations due to diabetes and peripheral arterial diseases, which occur in 45 per 100,000 individuals and disproportionately affect minority individuals [3,7].

In an analysis of the National Trauma database between the years 2000 and 2004, upper limb amputations were more likely to be seen than lower limb amputations in motor vehicle crashes. Motorcyclists and pedestrians were more likely to sustain a lower limb amputation [8]. Machinery, power tools, explosions, self-inflicted injury and assaults, and power tools are among the most common reasons for traumatic upper limb amputations [8]. Electrical burn is an uncommon cause of upper extremity amputation. Heating causes coagulative necrosis, and the passage of the electrical current through the tissues causes disruption of cell membranes [9]. Men are at far greater risk for traumatic amputation than women are, demonstrating about 6.6 times the female rate for minor amputations of the finger and hand [4].

Traumatic amputations often result in irregularly shaped residual limbs and frequently require skin grafts. Efforts to reduce edema and to promote proper limb shaping should be instituted as soon as possible [10]. The level of amputation is the single most important determinant of function after amputation. The primary surgical principle is to save as much limb as possible while ensuring removal of devitalized tissues and residual limb wound healing. Saving of the most distal joint possible dramatically improves the amputee’s function. The elbow joint, for instance, when it is preserved, allows the arm to function in carrying and supporting activities. For the mangled hand, saving of any fingers or remnants provides reconstructive hand surgeons the possibility of constructing a hand that can perform grasping activities.

Rates of prosthetic rejection are high among upper limb amputees [5]. Persons sustaining upper limb amputations present complex rehabilitative needs that are ideally best managed by a rehabilitation center with therapists, prosthetists, and physicians possessing specialized knowledge and experience. Proper rehabilitation and a comfortable and functional prosthesis will facilitate functional restoration. Vocational counseling and vocational retraining are vital aspects of any program as this condition often afflicts young, vocationally productive persons, primarily men. A continuum of care is vital to successful rehabilitation. Patients must be transitioned effectively from the inpatient postsurgical unit, sometimes to an inpatient rehabilitation unit and always to a long-term outpatient rehabilitation and prosthetic program.

Symptoms

Congenital upper limb amputees may report no specific symptoms except the lack of full upper extremity function. In contrast, traumatic upper limb amputees may describe phantom pain (pain perceived in the missing part of the limb) or phantom sensation (nonpainful perceptions of the missing part of the limb). Discomfort with prosthetic fit or skin breakdown on the residual limb may be reported in prosthetic users.

Physical Examination

Upper limb amputees require a thorough musculoskeletal examination that includes muscle strength testing, sensory testing, and examination of the contralateral limb. Examination of the residual limb should assess for areas of skin breakdown, redness, painful neuroma, and volume changes that could affect prosthetic fit. Persons with traumatic amputations of the upper limb can have brachial plexus injuries or rotator cuff tears that weaken the residual upper limb muscles. Insensate skin can predispose a patient to breakdown at the site of contact with a prosthesis. Joint range of motion should be assessed. In particular, the scapulothoracic motion is important as protraction of the scapulae provides the force for a dual-control cable system for body-powered prostheses. Reduced elbow or shoulder range of motion from heterotopic ossification, joint capsule contracture, or muscle contracture can impede maximum recovery of function or use of a prosthesis.

Functional Limitations

An upper limb amputee’s functional status depends on the level of amputation. Persons with finger loss (not including the thumb) are quite functional without a prosthesis. Persons with thumb amputations lose the ability to grip large objects as well as fine motor skills that require opposition with another finger. Reconstructive surgery by pollicization with another remaining finger dramatically improves hand function.

Transradial and transhumeral amputees lose hand function and have limitations in basic and higher level activities of daily living, such as dressing. Jang and colleagues [11] surveyed upper extremity amputees regarding the impact on activities of daily living. Subjects reported difficulty with complex tasks and either changed jobs or became unemployed. The most common difficulties in daily living were lacing shoes, using scissors, and removing bottle tops [11]. Upper limb amputees frequently sustain new vocational limitations that can preclude return to their previous work activities. Most persons can adapt to almost all basic daily activities with use of the intact contralateral hand and upper limb.

Prosthetic devices may or may not improve function. Some amputees find upper limb prosthetic devices cumbersome, discarding their use altogether. Datta and colleagues [12] found a 73.2% return to work rate after upper limb amputation, although 66.6% had to change jobs. The overall rejection rate of the prosthesis in this study population of predominantly traumatic upper limb amputees was about 34%. The vast majority used the prosthesis primarily for cosmesis; 25% of patients reported that the prosthesis was beneficial for driving, and a small proportion used it for employment and recreational activities. Some amputees require a specialized prosthesis to continue their specific work-related activities. Recreational activities such as golf, tennis, and other sports can often be accomplished with the use of adaptive prosthetic devices designed for these specific purposes. Return after amputation to such enjoyable pursuits can be quite therapeutic.

Diagnostic Testing

No special diagnostic testing is generally required beyond a careful physical examination. If there is weakness of the limb, electrodiagnostic testing may clarify whether a plexopathy is also present. Radiographs may be necessary to evaluate for osteomyelitis, heterotopic ossification, or a bone spur in the distal limb causing poor prosthetic fit. If myoelectric prostheses are considered, electromyographic signals and voluntary control of key muscles can be tested by a specialized therapist to determine if such control is possible and to train the amputee to independently use these potential control muscles.

Management of persons with upper limb amputations involves a continuum of care [3,10,13–16]. This begins with provision of preoperative information when the amputation is elective, as in the case of cancer. The overriding concern in planning the amputation is to save all possible length, particularly the elbow joint. This preserves elbow flexion and prevents the need for a dual-control cable system. The early input of a physiatrist, nurse, and physical or occupational therapist with expertise in this area is highly advantageous. Early involvement of the rehabilitation team can provide helpful information about prosthetic options, the rehabilitation continuum, and what can be expected after amputation (such as phantom sensations).

Immediately after amputation, the primary goals are wound healing, edema control, and prevention of contractures and deconditioning. Persons sustaining upper limb amputations due to trauma or cancer generally have normal underlying blood supply, and most surgical sites can readily heal. Edema is prevented by use of a shrinker sock, elastic bandage wrapping with a figure-of-eight technique that provides pressure distally without choking the limb, or a rigid dressing system. In sophisticated centers, immediate postoperative prosthesis fitting in the operating room is implemented. The immediate postoperative prosthesis is placed over the limb after padding of the skin with soft dressings. The immediate postoperative prosthesis accommodates surgical drains yet prevents the formation of edema. Prosthetic components can be attached to the immediate postoperative prosthesis and early training implemented.

Postoperative early identification and treatment of adherent scar tissue are important. Scar can form between skin, muscle, and bone. These adherences can cause pain when muscles are contracted or a joint is moved during operation of the prosthesis [17].

Residual limb pain and phantom pain are two conditions that can affect patients with upper limb amputations [14]. Phantom sensations are common; yet fortunately, disabling phantom pain occurs in only about 5% of amputees [13]. Despite the many interventions used for phantom pain, there are no uniformly effective treatments [13,15]. Medication and physical modalities must be tried in a rational fashion to determine the most effective intervention. Physical modalities include a transcutaneous electrical nerve stimulation unit, physical manipulation, and massage of the residual limb [13]. Fitting of a comfortable prosthesis can often help reduce these painful sensations.

Neuromodulating medications, such as tricyclic antidepressants and antiepileptics (gabapentin and pregabalin), are frequently used with variable results [13,15]. Beta blockers (propranolol and atenolol) have been found to be somewhat effective in treating phantom pain [13]. If patients require cardiac or hypertension medications, the choice of a beta blocker may serve two purposes for these amputees with phantom pain.

Opiates may be effective for these problems when other methods fail to relieve phantom pain [15]. If it is anticipated that the person with phantom pain will need analgesia for a long period, long-acting opiates should be used. Longer acting opiates have less habituation and addiction potential. Most amputees with phantom pain have intermittent severe pain that can be treated with small doses on an as-needed basis of a short-acting opiate, such as oxycodone. For the few patients with severe, unremitting, phantom and residual limb pain, referral to a specialized pain center is suggested.

Rehabilitative and Prosthetic Management

Prevention of contractures in the residual limb and prevention of generalized deconditioning are important goals of early rehabilitation. Any other injuries, as are common in persons sustaining severe trauma, should be identified and rehabilitation efforts directed at their remediation. For body-powered prostheses, scapulothoracic motion provides power through a cable system to operate the prosthesis. Therefore, to optimize function, therapeutic exercise to optimize shoulder range of motion and scapular stabilization is important. Likewise, elbow contractures or shoulder contractures or capsulitis will severely impede maximal prosthetic use, and these problems should be aggressively addressed. Early training in activity of daily living skills should be pursued as well. Therapies should be directed toward amelioration of weakness through exercises or of contractures through active-assisted range of motion exercises and prolonged stretching.

A detailed discussion of prosthetic devices is beyond the scope of this chapter, and consultation with a skilled prosthetist and physiatrist is desirable. Prostheses can serve a cosmetic (passive) role or a functional role, or both [18]. In general, there are two types, body-powered and myoelectric devices [3,16,18]. Body-powered prostheses enable an amputee to harness residual body movements to generate controlled movement and force of a terminal device [18]. Body-powered devices are usually less cosmetic and associated with limited range of motion and limited prehensile strength, yet they are less expensive and much more durable [18]. Myoelectric prostheses are controlled by electrical signals generated in muscles from the remaining residual limb or shoulder girdle. Myoelectric prosthetic devices extract signals from remaining muscles under voluntary control to activate and to control drive motors in the prosthesis [19]. These devices are expensive, and special prosthetic skills are required to fabricate and to maintain them, but they are generally more cosmetic in appearance and well suited for selected patients. Prosthetic functional outcomes depend on an individual’s goals related to cosmesis, function, and psychological factors [17]. Prosthetic prescription should also consider an individual’s level of cognitive functioning and ability to learn to operate a device. Skin breakdown can occur over bone prominences, where there are skin grafts, or where skin is adherent to underlying bone. Alteration of the prosthetic socket and suspension systems or temporary discontinuation of prosthetic use until the skin has healed may be necessary.

To meet the needs of military amputees, the Defense Advanced Research Projects Agency (DARPA) has funded development of two advanced upper limb prosthetic solutions. One of the technologies uses neural control; the other, DEKA arm, uses a “strap and go” system that can be controlled by noninvasive means [5]. Implementation of advanced technology requires a coordinated approach using multiple members of the rehabilitation team. Success is largely contingent on the availability of highly trained and specialized personnel to fit and train amputees and resources to pay for these services [5]. Telemedicine may help overcome some of these barriers. The field of upper extremity prosthetics is changing with the development of implantable neurologic sensing devices and targeted muscle innervation. Targeted motor reinnervation incorporates the transfer of residual peripheral nerves into muscles in or near the residual limb, with subsequent reinnervation of those muscles. By use of these surface electromyographic signals that relate directly to the original function of the limb, control of the externally powered prosthesis occurs [20]. Multidextrous terminal devices may soon be available [17].

Procedures

Most procedures related to the care of upper extremity amputees focus on pain management techniques, such as injection of local anesthetic around a painful neuroma, nerve blocks, massage, or chiropractic manipulation. Acupuncture, hypnosis, and biofeedback have also been used in the management of phantom limb pain with variable success [15].

Surgery

Revision surgeries are sometimes necessary to remove bone spurs that interfere with prosthetic fitting. The initial surgery should spare all length possible, particularly the elbow joint. A well-healed surgical site with good distal soft tissue coverage of the bone end is an optimal result that facilitates prosthetic use. In addition, surgical treatment of adherent scar tissue may be necessary to improve function of a prosthesis. In a study of combat-related upper extremity amputations, 42% underwent revision surgery. The most common indications for revision surgery, in order of decreasing frequency, are heterotopic ossification excision, wound infection, neuroma excision, wound dehiscence, scar revision, and contracture release. In the group that underwent revision surgery, regular prosthesis use increased from 19% before the revision to 87% after it [21].

Potential Disease Complications

As a result of the upper limb amputation, residual limb pain, including severe phantom pain, can occur. Joint contractures can develop in the remaining part of the limb, as can frozen shoulder and adhesive capsulitis. This is a particular concern with coexistent peripheral nerve or brachial plexus injury. Self-reported musculoskeletal pain is more frequent in upper limb amputees than in controls, frequently located in the neck, upper back, and shoulder region [22].

Depression brought on by the difficulties of adjusting to limb loss is reported. Psychological counseling and support groups incorporating peer support are valuable resources.

Potential Treatment Complications

Surgical complications include postoperative wound infections and postoperative failure of the surgical wounds to heal. Neuroma formation can occur after transection of a nerve. Burying the nerve ending under large soft tissue masses may reduce the likelihood of neuroma irritation.

Many medications used in the treatment of phantom pain associated with amputations have potential side effects, including dry mouth, constipation, weight gain, mental cloudiness, cardiovascular effects, and addiction. The side effect profiles vary by the medication class and dosage.

Skin breakdown from a poorly fitting prosthesis can occur. This can be aggravated by hyperhidrosis, folliculitis, or poor hygiene.

Overuse injuries in the nonamputated limb reportedly are higher than expected in the normal population [12]. These include repetitive strain-type injuries due to the individual’s performing certain tasks with poor body posture and ergonomics [23].