Extremity Amputations: Principles, Techniques, and Recent Advances

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Extremity Amputations: Principles, Techniques, and Recent Advances 10 Extremity Amputations: Principles, Techniques, and Recent Advances Carol D. Morris, MD, MS Benjamin K. Potter, MD Edward A. Athanasian, MD Valerae O. Lewis, MD Abstract require considerable preoperative plan- It is estimated that approximately 1.7 million Americans are living with the loss of a ning, knowledge of prosthetic design, limb, and this number is expected to nearly double by 2050. The most common reasons and consideration of postoperative ex- for amputation include vascular compromise, trauma, cancer, and congenital deformities. pectations. This chapter reviews the Orthopaedic surgeons are often called on to manage patients requiring an amputation or principles and techniques for perform- those with amputation-related conditions. It is helpful to review the principles and techniques ing lower and upper limb amputations, for performing lower and upper limb amputations, with a focus on common complications with a focus on common complications and how to avoid them and to be familiar with recent advances in prosthetic design and and how to avoid them, and discusses management of a residual limb. recent advances in prosthetic design Instr Course Lect 2015;64:105–117. and management of the residual limb. It is estimated that approximately have decreased over time, but compli- Upper Limb Amputations 1.7 million Americans are living with cations from vascular disease leading to Amputation Levels the loss of a limb, and this number is amputation have increased. The num- Fingertip amputations are com monly expected to nearly double by 2050. Vas- ber of amputations performed for con- seen in the emergency department. cular compromise, trauma, cancer, and genital deformities has remained steady. Treatment methods vary and are large- congenital deformities are among the Although amputation is typically ly based on the level of amputation, the most common reasons for amputation. considered a nonchallenging surgical angle of injury, and soft-tissue status. Traumatic and neoplastic etiologies procedure, good functional results Transverse injuries may be allowed to heal by secondary intention in most cas- es because skin match and sensation Dr. Morris or an immediate family member serves as a board member, owner, offi cer, or committee member of the American Academy of Orthopaedic Surgeons. Dr. Potter or an immediate family member serves as a board member, owner, offi cer, or are often superior to grafting. At times, committee member of the Society of Military Orthopaedic Surgeons and the American Academy of Orthopaedic Surgeons. bone shortening may be required. V-Y Dr. Lewis or an immediate family member has received research or institutional support from Stryker and serves as a board Atasoy and Cutler fl aps may be used on member, owner, offi cer, or committee member of the American Academy of Orthopaedic Surgeons and the Western Ortho- 1 paedic Association. Neither Dr. Athanasian nor any immediate family member has received anything of value from or has occasion. Severe oblique injuries may stock or stock options held in a commercial company or institution related directly or indirectly to the subject of this chapter. require full-thickness skin grafting, © 2015 AAOS Instructional Course Lectures, Volume 64 105 Orthopaedic Medicine and Practice volar advancement fl aps, or cover- age from adjacent digits (for example, cross-fi nger fl aps, reverse cross-fi nger fl aps, and dorsal metacarpal artery fl aps). More proximal-level traumatic digit amputations are most commonly closed directly with some shortening or conversion to a ray amputation. In- dications for ray amputation must take into account individual patient con- siderations. Preoperative consultation should include discussion of cosmetic change, neuroma formation, and grip strength reduction.2 Replantation may be considered for amputations in sin- gle digits distal to the fl exor digitorum Figure 1 Clinical photograph of a superfi cialis insertion on the middle Figure 2 Clinical photograph of a double ray (index and middle fi nger) ring and small fi nger amputation for phalanx, multiple digits, and thumbs amputation for sarcoma. sarcoma. and in children. rarely will metacarpophalangeal dis- Elective Digit and articulation be favored by patients. highest rate of painful neuromas.4,5 Ray Amputation Ray amputation without transpo- Phantom sensation is common, but Elective digit amputation may be in- sition is an excellent treatment op- phantom pain is infrequent. Rarely, dicated in patients with vascular defi - tion for severe ring avulsion injuries painful neuromas may require reexci- ciency, infection, or tumors. In the or malignant tumors of the digits.2 sion or cryoablation. elective setting, the level of amputa- Transposition may be considered for Multiple ray amputation may be tion and fl ap design can be carefully the treatment of middle fi nger lesions; required in the presence of tumor or planned. Fish-mouth incisions often however, it is often not needed. During severe trauma. The defect produced have the optimal appearance. Vo- this procedure, the base of the index by multiple ray amputation is much lar fl aps are particularly useful in the metacarpal is osteotomized, and the en- more apparent (Figures 1 and 2). setting of distal interphalangeal joint tire digit is transposed to the position of Grip strength is often dramatically de- disarticulation or interphalangeal dis- the middle ray. The index metacarpal is creased. In the tumor setting, it may be articulation in the thumb. The volar then fi xed to the base of the transected reduced by 75%.5 Function is markedly skin provides excellent sensation and middle fi nger metacarpal. Attention to diminished. durable skin and may maximize tactile digit rotation is critical. This procedure Thumb ray amputation is not fre- sensation. The level of amputation re- can improve the appearance of the hand quently indicated. Whenever possible, quired may infl uence the decision for but at the risk of malrotation, nonunion, thumb salvage procedures should be ray amputation. When amputation at and (in the presence of tumors) contam- considered.6 Tumors distal to the in- the proximal phalanx level is indicated ination of the index ray. terphalangeal joint often can be treated in the digits, ray amputation should be Metacarpal ligament reconstruction safely with interphalangeal disarticu- considered. The cosmetic appearance allows narrowing of the defect and lation. Tumors at the proximal pha- and function are often superior in the improves cosmetic appearance. Grip lanx level often can be widely excised setting of ray amputation. If breadth of strength is often reduced by approx- with reconstruction of the defect using the palm is important for function, ray imately 30%.3 Neuroma formation is bone, tendon, and vascular and nerve amputation may not be elected. Only common, and the index ray has the grafts with microsurgical soft-tissue 106 © 2015 AAOS Instructional Course Lectures, Volume 64 Extremity Amputations: Principles, Techniques, and Recent Advances Chapter 10 reconstruction. Ray amputation of the assistive devices and greater use of the thumb produces a substantial function- contralateral limb. Transhumeral-level al defi cit. Toe-to-thumb transfer or in- amputation may be required for severe dex pollicization may be reconstruction forearm trauma, traumatic amputation, options in this setting. or tumors of the proximal forearm or Wrist disarticulation is rarely re- elbow with involvement of multiple ma- quired in the tumor setting. Large jor nerves. Wide excision of the entire tumors in the region of the wrist usu- elbow with reconstruction may be an al- ally require forearm-level amputation. ternative if major nerves can be spared. Smaller tumors may be amenable to In the presence of a malignant tu- wide excision and reconstruction us- mor, the humerus-level amputation site ing vascularized and nonvascularized is determined in large part by the level Figure 3 Intraoperative pho- bone grafts with wrist arthrodesis. At of injury or the level of amputation re- tograph of a myoplasty for a forearm-level amputation. times, bone transport can be used to quired for achieving a wide excision. bridge defects at the wrist. However, In general, amputations that maximize wrist disarticulation may be considered length are preferred, as are anterior and posteriorly or anteriorly. Vessels are su- in the trauma setting when replanta- posterior fi sh-mouth–type fl aps. The ture ligated, nerves are transected prox- tion is not possible. Equal fl aps dorsally triceps and brachialis are used for myo- imally, and the clavicle is disarticulated and palmarly are ideal, but the extent of plasty closure. Nerves are transected at the sternum or transected medially. soft-tissue injury may determine which proximally to minimize pain from neu- Skin fl aps may be determined by the fl aps are appropriate. romas. Suture ligation of vessels is pre- extent of tumor contamination and Forearm-level amputation may be ferred to control proximal level vessels. previous surgical procedures. Preoper- required for large wrist-level or carpal Shoulder disarticulation may be re- ative plastic surgery consultation may tunnel–based tumors. This level of quired for very proximal-level humeral be helpful in planning closure. At times, amputation is functionally devastat- amputations or when the presence of a fi llet forearm fl ap from the amputated ing. Because patients may have diffi - malignancy dictates the need for am- limb may facilitate closure.8 culty coping with the loss, preoperative putation at the level of the joint. Most psychological counseling should be commonly, a lateral fl ap is used for cov- Lower Limb Amputations routinely considered. Most com monly, erage. If the deltoid can be spared, it is General Principles when major nerves can be spared, incorporated into the fl ap. More prox- Between 30,000 and 40,000 lower wide excision and reconstruction are imal level amputations are commonly limb amputations are performed in preferred. Fish-mouth incisions with associated with phantom sensation and the United States annually, and this volar and dorsal fl aps are ideal.
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