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550 Part III Therapeutic Interventions

cal procedures. Collaboration between the surgeon, physia-trist, patient, prosthetist, therapists, and other rehabilitationteam members guarantees that the patient receives optimalsurgical and rehabilitation care. This chapter is written toassist the surgical and rehabilitation team in their efforts tocollaborate and maximize the patients functional outcome.An overview of surgical principles is presented rst, fol-

lowed by a presentation of prosthetic restoration andrehabilitation.

SURGICAL PRINCIPLESGeneral PrinciplesUpper-extremity amputation is performed infrequently. Asa result, few surgeons have the opportunity to work withupper-extremity amputees. Surgeons often consult withphysiatrists to advise them regarding the prosthetic andrehabilitation implications of surgical decisions. Collabora-tion between the surgical and rehabilitation team guaran-tees that the patient will experience the best surgical and

functional outcome.Many consider amputation a surgical failure: Thelimb could not be saved. However, amputation does notequate to failure. New surgical techniques and prosthetictechnology make it possible for amputation to be a part of an overall plan of upper-extremity reconstruction, notsimply a surgery of last resort. Obviously, if amputation isnot necessary, it should not be done. But when it is the bestoption for the patient, amputation can be the basis of upper-limb reconstruction and the rst step in upper-extremity rehabilitation. Approaching the amputation as areconstructive procedure facilitates achieving a painless,cosmetic, and functional limb. This reconstructiveapproach, coupled with a patient-oriented approach,focuses the medical teams efforts on achieving a positivefunctional outcome as dened by the individuals needs.

The goal of successful rehabilitation is an individualwho can assume autonomy and responsibility for allaspects of his or her life. The patients attitude, as well asthe attitude of the surgical and rehabilitation team, is keyto achieving this goal. The patient needs to know that amultidisciplinary coordinated effort is being made to opti-mize upper-extremity repair and reconstruction.

In general, there are two types of amputation. Theopen amputation, also called a guil lotine amputation , is indi-cated when severe infection or sepsis is present. The ampu-tation wound is not closed; treatment is directed atresolution of the infection. Denitive closure is performedonce the infection has resolved. The second type, the closed or deniti ve amputation , involves primary closure of theamputation site. Denitive closure is indicated if the limbis not infected and wound healing is a reasonableexpectation.

Typically, the surgical incision is best placed in atransverse position, with anterior and posterior skin aps of

lost his arm in battle, held his shield using an iron pros-thetic hand during combat (per account by Pliny).

During the following centuries, a variety of deviceswere used to replace the upper extremity. By the sixteenthcentury, Ambroise Par, a French military surgeon,designed the forerunner of todays modern upper-extremity prosthesis. His design allowed the amputee to

passively position the hand and lock it into place. Thougha locksmith could duplicate his design, it was expensive. Asa result, Pars design was only available to the wealthy.

The commoner managed without a prosthesis or used aleather socket with a stationary hook.

In the nineteenth century, Peter Baliff, a dentist,designed the rst body-powered prosthesis, which usedproximal muscle force to produce a weak prosthetic graspand release. Though originally designed for the below-elbow (BE) amputee, it was soon modied for the above-elbow (AE) amputee using a chest lever to control the AEprosthesis. During this same period, Comte de Beaufortdeveloped the double spring hook, the forerunner of todays hook terminal device (TD).

The twentieth century brought major changes inupper-extremity prosthetics. The injuries during the worldwars, as well as the thalidomide tragedy of the late 1950s,accelerated the pace of prosthetic technology and research.After decades of research, the myoelectric prosthesesbecame a reality. These prostheses remain the most suc-cessful externally powered prostheses ever developed.

Though modern prostheses are not as elegant andcomplex as the human upper extremity and hand, thecurrent generation of upper-extremity amputees lead fulland productive lives because of the advances of prosthetictechnology and research (e.g., improved tting and suspen-sion techniques, new lightweight durable materials, andmore sophisticated body-powered and externally poweredcomponents).

Prosthetic technology changes rapidly. It is impossi-ble for a text of this type to keep pace with the rapidchanges and availability of new technology. However, thebasic principles of prosthetic restoration and rehabilitationafter upper-extremity amputation change little. Thischapter focuses on these basic principles. If the physiatristand other rehabilitation team members follow these funda-mental principles, the upper-extremity amputee willachieve the optimal prosthetic restoration and functionpossible with todays advanced technology. As in any eldof medicine, this text cannot substitute for the cliniciansneed to study ongoing research and to learn from onespatients and their experience.

The basic surgical principles of amputation arereviewed. Obviously, a trained surgeon is the appropriateprofessional to perform amputations. However, the physia-trist, and other rehabilitation team members, need tounderstand the surgical principles of limb amputation.

The informed rehabilitation specialist is able to discuss theprosthetic and rehabilitation implications of various surgi-


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Chapter 31 Upper-Extremity Amputat ion and Prosthet ic Rehabi li tat ion 551

equal length. With this technique, the surgical scar will beat the end of the residual limb where it will not be incontact with the prosthetic socket. Scar formation on theposterior or anterior surface of the residual limb causespain from the mechanical pressure of the prosthetic socket.Like other amputations, dog ears, soft-tissue projectionsfrom the medial or lateral end of the surgical incision, are

undesirable.Often plastic procedures, such as placement of skingrafts or aps, are required to preserve length and func-tion. The choice of the type of graft or ap depends onthe specic surgical needs and available viable tissue.Length is a crucial issue for amputations about the shoul-der and below the elbow. Split-thickness skin grafts caneffectively preserve needed length (5).

Bone section should be a clean cut across the level,with rough surfaces smoothed. The shaping of the bonemust be compatible with future prosthetic use and sockettting. In the case of disarticulation, cartilage surfaces arepreserved. The articular cartilage provides a weight-bearing surface, and in children, prevents bony overgrowth

at the distal end of the residual limb. The muscle and tendons are divided distal to the siteof bone sectioning. Except for in digits, a myoplasty is typi-cally performed. Muscles, at their normal resting length,are sewn to their antagonists to secure them together. Amyodesis, which secures the tendon and muscle to thebone, is another option. If the distal musculature andtendons are not secured, they will retract proximally. If thisoccurs, the patient is not able to use these muscles tocontrol the residual limb or use these muscles for futuremyoelectric control sites.

Neuromas are an inevitable consequence of surgicalsectioning of a peripheral nerve. During amputation, nervedivision must be done carefully. The involved nervesshould be isolated, gentle traction should be applied, andthen the nerves sharply sectioned 2 to 4cm proximal to theosteotomy site (4). Once the nerve is sectioned, traction isrelieved, allowing the nerve to retract into proximal tissues.

This technique allows the neuroma to develop deep in softtissues, where irritation from scarring or pressure is lesslikely to occur. Meticulous surgical techniques will ensurethat neuromas form away from areas of potential irritationcaused by the prosthetic socket or components. Neuromasthat develop in exion crease regions trigger acute andchronic neurogenic pain.

Lastly, closure should be meticulous. Closureshould be done in such a way as to avoid the developmentof adherent scar, redundant tissue, or an irregularly shapedresidual limb. Especially in the AE amputee, redundanttissue should be avoided. Excess soft tissue makesprosthetic socket tting and prosthetic control difcult.

Characteristics of a residual upper extremity suitablefor prosthetic tting include a cylindrical limb with a well-placed scar, good skin coverage, adequate soft-tissuecoverage, and intact sensation. Ideally, the patient should

be pain free. If this is not feasible, pain should be suf-ciently controlled so that the person is able to tolerate theprosthesis.

In summary, the goals of surgical amputation are to1) preserve functional length of the extremity, 2) preserveuseful sensation, 3) prevent symptomatic neuromas or painsyndromes, 4) prevent adjacent joint contractures, 5) mini-

mize recovery time, and 6) achieve early prosthetic ttingto facilitate return to work, activities of daily living (ADLs),recreation, and socialization (6).

Lastly, the development of sophisticated micro-surgery techniques makes upper-limb replantation andreconstruction feasible. In some situations of traumaticlimb loss, replantation is an option; replantation of theproximal part of the arm is less successful than BE replan-tation. Kleinert and others (79) suggested that the lowersuccess rate is secondary to warm ischemia affecting agreater muscle mass. Additionally, reinnervation mustoccur over a much longer segment in proximal replanta-tion. If replantation is performed, it is most successful inthe very young patient whose injuries do not preclude

skeletal and neurovascular reattachment (10). Functionalneurologic recovery is best in children. Since replantationis not without risk, the patients overall status, the durationof limb ischemia, and the likelihood of metabolic replanta-tion toxemia must be considered (11).

Selection of Amputation Site The level of amputation is dictated by the site of trauma,tumor, or pathology. Though there is limited control overthe etiology and its effects, the surgeon may have somechoice of the amputation level. The surgeon must choosethe most distal amputation site that will allow satisfactoryhealing, prosthetic restoration, and rehabilitation. Judiciousselection of the surgical level, implementation of appropri-ate amputation techniques, and careful tissue managementwill have a long-lasting positive inuence on future pros-thetic restoration, rehabilitation, and lifestyle.

Anatomically, there are many levels of amputation,including partial hand, wrist disarticulation (WD), BE (alsocalled a transradial) amputation, AE (or transhumeral)amputation, shoulder disarticulation (SD), and forequarter(FQ) amputation (Fig. 31-1).

Partial Hand Amputations The hand is a very complex and intricate element of thehuman upper extremity. Object manipulation, precisionpinch, and power grasp are the primary functions of thehand. Precision pinch requires, at minimum, two opposingdigits. Not only must the digits be capable of motion, butthey must also have functional sensation. Pinch can be sub-divided into three basic types: tip-to-tip pinch, three-digitpinch, and lateral pinch. In the normal hand, the thumbopposing the index and long ngers, also called the radial tripod , creates a precise pinch.

Power grasp is the action of holding something


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Primary suture or closure by secondary intention is accept-able and prevents the morbidity associated with skin graft-ing. However with bone exposure, one must shorten thebone or cover using a ap (12). If the amputation isthrough the IP joint, the condyles are usually shaped toimprove cosmesis. Of adults with a ngertip injury andpulp loss, 30% to 50% have cold intolerance or aberrationof sensibility regardless of the technique used (6).

The exors and extensors of the hand are treateddifferently than other upper-extremity muscles. Generally,myodesis or myoplasty is advised when sectioning musclesand tendons. In the hand, however, the exor and extensortendons are divided and allowed to retract. These tendonsare not sewn together. This prevents the development of anger exor condition, known as quadriga . Amputation

securely against the palm of the hand. The prerequisitesfor a power grasp are sufcient hand width, at least threemetacarpal heads, and mobile metacarpophalangeal(MCP) and interphalangeal (IP) joints. The thumb andindex nger facilitate control and strengthen grasp, but themiddle, ring, and small ngers are also considered key ele-ments. The fth nger, or so-called small digit, superciallyseems unimportant but it prevents the object slipping awayfrom the palm by creating an ulnar cup. It is essential forgripping tools. The index nger provides 50% of the sta-bility and 20% of the strength of the power grasp (6).

The most common type of upper-extremity amputa-tion is the ngertip amputation. Some propose graftingwhile others propose conservative treatment if the amputa-tion is distal to the distal interphalangeal (DIP) joint.

5090%

3050%

Level and lossUpper/extremity amputations

Forequarter amputation (FQ)

Shoulder disarticulation (SD)

Short above elbow (AE)

030% Very short above elbow (AE)

Standard above elbow (AE)

90100% Long above elbow (AE)

Elbow disarticulation (ED)

035%Very short below elbow (BE)

3555%Short below elbow (BE)

5590%Long below elbow (BE)

90100%Wrist disarticulation (WD)

Carpal disarticulation (CD)

Transmetacarpal

Figure 31-1. The various anatomic levels of an upper-extremity amputation.


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through the middle phalanx distal to the exor digitorumsublimis (FDS) preserves functional exion of the middlephalanx. However, if the FDS insertion cannot be pre-served, amputation through the proximal interphalangeal(PIP) joint is usually performed.

With loss of the long or ring nger at the level of theMCP joint, or the presence of a very short digital

residuum, small objects can fall out of the hand. If theindividual cannot voluntarily ex the digital remnant, orthe amputation is at the level of the MCP joint, a ray dele-tion or transposition may increase function and improvecosmesis. If transposition is not possible, then deletion withclosure of the central defect creates a functional and cos-metic hand.

Ray amputations are often done electively to mini-mize disability from a previous injury to a digit. This isusually not done at the time of trauma because the patientneeds to determine if a digit stump is useful or not. If theindex nger is very short and cannot be used for pinch, theremnant may interfere with the individual pinchingbetween the thumb and the middle nger. Since the index

nger provides stability to the power grip, signicant effortis made to preserve the length and sensation of the indexnger, particularly in manual laborers. Resection of theindex ray can reduce grip strength by 20%, but canmarkedly improve cosmesis (13).

Though the underlying pathology primarily dictatesthe level of amputation, the patients lifestyle and occupa-tion also impact this decision. The jeweler who has lost anindex nger at the MCP joint requires preservation of aprecise pinch, or if not possible, hand reconstruction torestore precise pinch. This may require resection of theindex ray to prevent it from mechanically interfering withopposition of the thumb and long nger. However, digitloss at the same level in a construction worker dictates adifferent approach. In this case, preservation of the ray of the index nger preserves power grip by preserving palmarwidth and stability.

The thumb provides 40% to 50% of hand functionand 30% of upper-extremity function. It is important forpower and precision grasp. Length, sensation, and stabilityof the thumb for opposition are high priorities. When indi-cated, skin grafting can preserve length, allowing sufcientresiduum for pinch and grip. The precise length needed topreserve thumb function is controversial, but a minimumlength of 2cm has been proposed (14). Distraction, bonegrafting, and phalangealization of the rst web space areoptions available to lengthen the thumb remnant. It isimportant to remember that the replanted thumb, as wellas the reconstructed thumb, will not necessarily havenormal function (15). If pollicization is required, the indexnger is the best digit to use (16).

For multiple-digit amputation, it is important toremember that rudimentary grasp requires a cleft betweentwo opposing poles that are rotated to be opposite to eachother or can be adducted together (parallel adduction).

Wrist Disarticu lationIn the past, WD gained popularity because it preserves thearticular surface of the distal radioulnar joint and maximalforearm supination and pronation. WD provides a tolerantend-bearing surface. The shape of the distal end is con-ducive to a self-suspending socket, though additional strapsmay be required for heavy work (17).

WD has disadvantages, however. The broaddistal socket required to accommodate the residual styloidprocesses makes fabricating an aesthetically acceptableprosthesis difcult. The styloid prominences can bereduced at the time of disarticulation but some of theadvantage of the wide distal residual limb for a self-suspending socket is lost. The addition of a prostheticwrist unit, which allows for an interchange of TDs suchas hands and hooks on the prosthesis, can make the arti-cial limb longer than the intact arm. This is more obviouswith a prosthetic hand than with a hook. Extra lengthreduces cosmesis and interferes with midline hand tomouth activities. Consequently, the selection of wrist unitsand TDs is limited. Additionally, if a persons goal is to

use a myoelectric prosthesis, disarticulation is a poor choicebecause myoelectric units also add length to the prostheticforearm. A long transradial amputation would be a betterchoice if the patient is a candidate for a myoelectricprosthesis.

Transradial or Below-Elbow AmputationFor transradial or BE amputation, the forearm is dividedinto three lengths: the distal, middle, and proximal thirds.It is important to conserve all possible length of the limb(18), with a minimum of 10cm below the lateral epi-condyle of the humerus being preferred. Individualswith a very short forearm remnant have difculty tolerat-ing the weight of a BE prosthesis. However, it is worth-while to save even 4 to 5cm of the limb if the brachialis isintact and the biceps brachii can be divided and trans-ferred to the ulna, to add control and facilitate prosthetictting (19). The radius and ulna are typically sectioned atthe same length. The elbow joint should be saved when-ever feasible. Natural exion and extension are preservedand one less prosthetic joint is required. Many authorscontend that preservation of the elbow cannot beoveremphasized (1).

A longer residuum provides a greater lever arm andconsequently greater forearm strength and power. Greaterforearm rotation is preserved. An amputation at 2cm ormore proximal to the wrist allows more room for pros-thetic components (1,20). At this level, approximately 70%to 80% of natural pronation and supination are preserved.As the forearm length decreases to 60% or shorter, there israpid loss of rotation until no natural pronation or supina-tion is preserved. Without natural forearm supination andpronation, a method of rotating the forearm must beincorporated in the prosthesis.


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width, and contours. Not only is this aesthetically morepleasing, but also the shoulder contours provide a morestable purchase for the prosthetic socket. Additionally, theshoulder contour signicantly affects the t of clothing.

This is particularly important for womens clothing, such asbras and other undergarments. The contour and symmetryof the female breast are relatively preserved because thepectoralis major insertion is not disrupted as with SD.Lastly, if the deltoid remains, it potentially can be used asa site for myoelectric control.

At this level, the upper-extremity residuum providesminimal function. The more proximal an amputation is, theless functional are the available prostheses. Clinically, it isobserved that the more proximal the upper-extremityamputation is, the higher the prosthetic rejection rate is.Clinical experience suggests that externally powered pros-theses are rejected less frequently than body-powered pros-theses. The externally powered hand is more cosmetic andmore functional than the mechanical hand or hook (24,25).However, these prostheses are heavy. Because these prosthe-ses are expensive, many funding agencies will not nance anexternally powered prostheses at this level of amputation.

Juvenile Amputees Though the surgical principles of pediatric amputation aresimilar to those for the adult, there are two major distinc-tions: A disarticulation is preferred to a transdiaphysealsection and more heroic efforts are indicated to conservelength (26). In children, epiphyseal preservation is impor-tant. The growth potential of the distal epiphyses is greaterthan that of the proximal radial and ulnar epiphyses, while

Elbow Disarticulat ionElbow disarticulation (ED) has several advantages. Preser-vation of the humeral condylar ares facilitates prostheticsuspension. Because the humeral condyles t snugly intothe prosthetic socket, humeral rotation is efciently trans-mitted to the prosthesis. ED provides a longer lever armthan an AE amputation does. Additionally, the distal end is

pressure tolerant since the articular cartilage is preserved.Cosmesis is the primary disadvantage of ED. The

distal end of the prosthesis is bulky. Fewer prostheticelbows are available. At this level, outside locking elbowhinges are required but they can damage clothing andreduce cosmesis. Myoelectric elbow units, such as the Utaharm, also create an abnormally long prosthetic arm. Toavoid this length differential, it is possible to t the patientwith a hybrid prosthesis fabricated with both body-powered and electronic components.

Transhumer al AmputationAmputation through the humerus can be done at severallevels. The transcondylar amputation, like ED, preserves

the condylar ares which can transmit humeral rotation tothe prosthesis. Like ED, an external hinge elbow joint isrequired, since other elbow units make the prosthetic limbabnormally long. The remaining humeral condyles requirea socket with a wide distal end, detracting from the overallappearance of the prosthesis.

A residual limb that is at least 10cm long, measuringfrom the axillary fold, is preferred according to manysources. The greater the upper-limb loss, the less humeralrotation is preserved. Designing the prosthesis with aninternal locking prosthetic elbow joint with a turntable forinternal and external rotation (21) offsets this loss to somedegree.

Shoulder Disarticulation and Forequart er AmputationAmputations at this level are uncommon. Tumor is theprimary cause (22), while major trauma is the second mostfrequent cause. Less than 3% of traumatic upper-extremityamputations occur at this level (23). Traumatic amputationat this level is frequently secondary to avulsion forces.

Congenital deciency occurs infrequently at thislevel. Like congenital deciency at other levels, these limbsrarely need revision. Congenital limb absence ofteninvolves the additional problem of bony malformationsand vestiges of missing portions of the limb; therefore,prosthetic tting is often more challenging. A fullunderstanding of the anatomy and function of the con-genitally decient limb is key for proper prosthesis selectionand tting, especially if surgical revision is beingconsidered.

Cosmesis is a major problem (Fig. 31-2). If thescapula can be retained, disgurement is less than thatwith a FQ limb loss. Though amputation through the sur-gical neck of the humerus is functionally equivalent to SD,retention of the surgical neck preserves shoulder fullness,

Figure 3 1-2 . Forequarter amputation results in the loss of

the normal shoulder contour and prole.


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in the humerus, the proximal epiphysis has greater growthpotential.

Disarticulation allows for undisturbed epiphysealbone growth, preserving longitudinal growth. Disarticula-tion also prevents the development of bony overgrowth atthe terminal bone. Since bony prominences (e.g., condyles)become less prominent with age, disarticulation does not

present the same cosmetic problems that are seen in adults.In children, bony overgrowth at the site of a trau-matic amputation is the most common postamputationcomplication. Occurring in about 10% to 30% of pedi-atric metaphyseal or diaphyseal transections, bony over-growth is most common in children less than 12 years old(27). Disarticulation prevents this complication.

The earliest sign of bony overgrowth is the develop-ment of an adventitious bursa between the distal end of the transected bone and the soft tissues. Typically anadvancing bony spike develops, irritating the bursa andlocal tissues. Not only pain develops, but also local infec-tion can occur. Terminal bone overgrowth occurs mostoften after humeral transection, followed by bular, tibial,

and femoral transections (27,28).Studies have shown that bony overgrowth is additiveappositional bone growth from the distal end of the tran-sected bone. Epiphysiodesis does not control the problemsince the bony overgrowth is not the result of epiphysealgrowth. In fact, epiphysiodesis will unnecessarily shortenthe residual limb, potentially causing further functional andcosmetic loss. Interestingly, bony overgrowth typically stopswith skeletal maturity (29).

Bony overgrowth occurs primarily in children whohave had a surgical or traumatic amputation. Childrenwith a congenitally decient limb, particularly those withamniotic band syndrome (30,31), may develop bony over-growth. This problem is also seen in adults whose amputa-tions are secondary to an electrical injury (32,33).

If prosthetic modication cannot control the prob-lems associated with bony overgrowth, surgical resectionremains the most effective option (34). Resection isrequired in about 10% of children (34).

OVERVIEW OF PROSTHETICS FORTHE UPPER EXTREMITYProstheses can be categorized in many ways: exoskeletalversus endoskeletal design, passive versus active, body-powered versus externally powered, and by anatomic level.Prostheses can also be identied by the stage of prostheticrestoration and rehabilitation.

The prosthesis with a rigid external structure iscalled an exoskeletal prosthesis . This type of prosthesis is moredurable than the endoskeletal prosthesis, which has a rigidinternal structure but a soft exterior. The hard externallayer of the exoskeletal prosthesis allows this prosthesis towithstand contact with hard or sharp surfaces. The

endoskeletal prosthesis has a soft removable outer cover,which allows easy access to the prosthetic components.

Though endoskeletal designs often weigh less, exoskeletal

prostheses are typically prescribed because of superiordurability.Some prostheses provide no active function, passively

replacing the missing body part. The appearance resem-bles the missing limb. These prostheses are chosen forcosmesis and their relative light weight. Highly sophisti-cated and nearly perfect anatomic replicas of the missinglimb are available but are very expensive.

Prostheses are also classied by power source, that is,body-powered versus externally powered prostheses. Thebody-powered prosthesis uses a system of straps and cablesto transfer energy of one body part to the prosthesis toperform a specic motion (Fig. 31-3). For example, the AEamputee uses scapular and humeral motion to operate aprosthetic elbow and hand. Externally powered systemsrely on an external source of energy to operate the pros-thesis. The most frequently used externally powered pros-thesis employs the myoelectric control system, but othersystems exist, including electric switch controls. Myoelectricprostheses use the electrical potential of a muscle to volun-tarily operate components of the prosthesis, for example,to open and close a prosthetic hand (Fig. 31-4).

Prostheses are also identied by the stage of rehabili-tation: the temporary and the denitive prosthesis. Thetemporary prosthesis, also called a preparatory or provisional prosthesis , is used while the residual limb volume is stabiliz-ing and the individual is learning how to use a prosthesis.

This period also allows the amputee to determine whichprosthetic components and options are most appropriate.A preparatory prosthesis can be very simple. For example,materials used to make the temporary socket can rangefrom casting materials to sophisticated thermoplastics.

Though the provisional or preparatory prosthesis is madewith the same attention to t and function as the denitiveprosthesis, the materials of the temporary prosthesis are

Figure-of-eight harnesswith O ring

Hook TD

Control cable

Socket

Cable housing

Tricepscuff

Figure 31-3. Illustration of a typical body-powered, orconventional, cable-controlled below-elbowprosthesis with a hook terminal device (TD).


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Patients can be tted while still in the operatingroom or tted early (i.e., within the rst 2 weeks) afteramputation. The techniques of immediate or early ttingremain underutilized, even though studies of both tech-niques have demonstrated high acceptance rates without

jeopardizing wound healing (3638). Early tting appearsto be the single most important variable predicting success-

ful prosthetic use.

Preparatory Prostheses The immediate postoperati ve prosthesis tting technique is available,but it is used infrequently. While still in the operatingroom, the patient is tted with an immediate postoperativeprosthesis made of a rigid dressing with minimal, but func-tional prosthetic components attached. The socket can beapplied once the surgical incision is closed. Initially, theincision is dressed with a light layer of bandages, andplaster or berglass is used to form a socket on thepatients residual limb. The immediate postoperative pros-thesis functions as the nal wound dressing.

Immediate postoperative tting has many advan-

tages, including controlling postoperative edema and pain.Reducing postoperative edema minimizes postoperativepain and phantom pain. The immediate postoperativeprosthesis conditions and shapes the residual limb, prepar-ing it for future prosthetic tting. Additionally, the immedi-ate postoperative prosthesis allows the occupationaltherapist (OT ) to begin training almost immediately. It isimportant that prosthetic training does not begin beforethe surgeon agrees. In some cases, the surgeon may allowthe OT to begin training within the rst 24 hours of surgery, whereas others prefer waiting several days. As aresult, the amputee experiences the immediate usefulnessof the residual limb and the prosthesis.

While immediate postoperative tting sounds ideal, itrequires an experienced, multidisciplinary, surgical andprosthetic rehabilitation team, available to t the prosthesisin the operating or recovery room and to ensure that thet is correct to prevent tissue damage and risk further limbloss. Most amputations are the result of trauma, however,and there is limited time to assemble an experienced multi-disciplinary team.

Earl y tting of a temporary prosthesis is morecommon than the immediate tting approach. Oncesutures are removed, about 1 to 2 weeks after surgery,tting is begun. Though early tting occurs duringMalones golden period, some (36) question whether use of the early tting technique results in as much acceptance asuse of the immediate tting approach. However, manyinvestigators (35,3741) found no appreciable differencebetween the success rate of prosthetic use between the twoprosthetic tting techniques.

Many of the same advantages of immediate postop-erative tting are also seen with early prosthetic tting.Bimanual activities are preserved and prosthetic accep-tance is high. However, the early tting approach has addi-

not as durable as those of the denitive prosthesis. Thepreparatory prosthesis is modied periodically to meet the

amputees advancing skill and to accommodate changes inthe residual limb volume and shape. At this phase of reha-bilitation, the nal design of the prosthesis is still evolving.

The denitive prosthesis is the nal or permanentprosthesis prescribed and fabricated for the individual. It isprescribed after the residual limb volume has stabilizedand when the patient is experienced using a prosthesis andthe patient and the rehabilitation team have determinedthe most appropriate prosthetic design.

The Principle of Early Prosthetic Fitting The most important development in the last 15 years of upper-extremity prosthetics is the realization that upper-extremity amputees need to be tted for a prosthesis early.Malone et al (35) found that patients tted within 30 daysof upper-extremity amputation, sometimes calledM alones golden period, demonstrate the greatest successin prosthetic acceptance and use. Previous to these obser-vations, most patients were tted with an upper-extremityprosthesis 3 to 6 months after surgery, or even later. Therejection rate was as high as 50%. Fitting a prosthesiswithin 4 weeks of upper-extremity amputation dramati-cally improves the long-term outcome. Some (36) centersreport success rates as high as 90%.

Early prosthetic tting preserves bimanual upper-extremity patterns, increasing prosthetic acceptance anduse. Minimizing the time period between loss of bilateralupper-extremity activity and the return of bilateral func-tion through prosthetic restoration maximizes success. If prosthetic tting is delayed, patients quickly learn to beone handed and forfeit the use of a prosthesis. They doactivities with one hand or expect others to perform two-handed activities for them. Some will avoid bimanualactivities alltogether. The goal of independence is

jeopardized.

Myoelectric orpowered hand

Motor

Battery

EMG amplifier

Dorsal electrode

Figure 3 1-4 . A typical myoelectrically controlled below-elbow prosthesis with a hand terminal device.EMG = electromyograph.


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tional advantages, including allowing a longer time for theincised tissues to heal and allowing the prosthetist moretime to design and fabricate an individualized prosthesisand use a greater variety of prosthetic components.

The bilateral upper-extremity amputee must receivea prosthesis early. Without a prosthesis, the amputee isdependent in virtually all aspects of everyday life. The

earlier a prosthesis is issued, the earlier training in hygiene,feeding, and self-care can begin. Immediate or early ttinghelps to decrease dependency and reduces some of thenegative psychological and social impact of bilateral ampu-tation. Though for somewhat different reasons, both theunilateral and the bilateral upper-extremity amputeeshould be t early.

The preparatory or provisional prosthesis may be abody-powered, myoelectrically controlled, or a combina-tion or hybrid system. This stage of wearing the prepara-tory prosthesis is a distinct step in prosthetic restorationand rehabilitation; it involves an evaluation to determinethe most appropriate prosthetic design for the individual.During this period, the amputee test drives the various

prosthetic designs and develops realistic expectations aboutwhat a prosthesis can and cannot do. The individual expe-riences rsthand the advantages and disadvantages of various sockets, suspension systems, elbow and wrist units,hands, and other terminal devices. Unfortunately, somefunding agencies do not nance a temporary prosthesisand will only pay for a permanent prosthesis. As a result,the amputees nancial situation may not allow for an eval-uation of various prosthetic designs.

Denitive Prostheses The nal or denitive prosthesis represents the culminationof all the experience and information gained during thepreparatory phase. The denitive prosthesis is the perma-nent one, the prosthesis the person is going to live with(Fig. 31-5). Test driving various provisional designs ensuresthat no major oversights occur in the design of the perma-nent prosthesis. Like the provisional prosthesis, the deni-tive prosthesis can be body powered, myoelectric, or ahybrid of both. The permanent prosthesis, which mustwithstand all types of activities over the long term, is con-structed with more durable materials than is the provi-sional prosthesis.

Upper-Extrem ity Prosthetic Control Systems The body-powered prosthesis, also called a mechanical prosthesis , is the conventional upper-extremity prosthesis. Esti-mates indicate that 90% of upper-extremity amputees whouse a prosthesis use a body-powered system at least parttime. Amputees prefer this system because it is relativelyinexpensive, durable, reliable, and functional. This systemprovides some sensory feedback via the cables and harnesscontrol systems (42). Many prefer the speed of operationand accuracy of body-powered prostheses. Because they donot require external sources of power, there are no batter-

ies to recharge or replace. However, many do not like theappearance of body-powered prostheses. In general, theyare less aesthetic and do not have the high-tech appealof the myoelectric system. A body-powered prosthesis hasa weaker grip than the myoelectric one, but it is moredurable for manual work such as lifting (4345).

The myoelectric system is the externally powered

system of choice and is the preference of many amputees.It harnesses the electrical potential of a contracting muscleto operate the prosthesis (Fig. 31-6). These prosthesesrequire minimal proximal muscle control and can be usedin all planes of motion (e.g., overhead reaching). Com-pared to body-powered prostheses, myoelectric prosthesesprovide a stronger, graded grasp. Though more expensivethan body-powered prostheses, they are often more cos-metic since many do not require a harness for suspension.However, some myoelectric TDs, such as the Greifer hook,are bulky and robot-looking. This appearance is unaccept-able to some (Fig. 31-7).

Myoelectric prostheses are expensive. They are com-paratively fragile devices and frequently break down.

Greater technical skill is needed to repair and maintainthese systems. Unlike the body-powered prostheses, myo-electric systems do not tolerate many environmentalfactors, such as dust and moisture. They are not as durableor as well suited as body-powered prostheses for manuallabor. Because the weight of the prosthesis is not trans-ferred to more proximal body parts, as in the body-powered systems, myoelectric prostheses create morepressure at the point of suspension, the distal part of thelimb. Additionally, they feel heavier to the user.

Precise criteria for determining the ideal controlsystem for each person do not exist. The patients lifestyle,needs, funding source, and personal preference dominatethe choice. Frequently, amputees own both a body-powered and a myoelectric prosthesis and then wear theprosthesis most appropriate for a particular situation. Forexample, the construction worker may use a body-poweredsystem on the job, but wear a myoelectric prosthesis atsocial events (46). Recently, hybrid systems, with bothbody-powered and myoelectric components, have becomemore popular, since these systems can provide the advan-tage of both body power and myoelectric power.

In summary, a typical prosthetic restoration andrehabilitation schedule has several stages. Initially, theamputee is tted with a prosthesis in the immediate orearly postamputation period. Over the next 2 to 6 weeks,tting and training with a preparatory body-powered pros-thesis occur. Once trained, and after prosthetic needs aredetermined, the amputee is tted with a denitive body-powered prosthesis. Typically, the amputee is ready for adenitive body-powered prosthesis approximately 6 to 12weeks after amputation. As a general rule, a person is ttedwith a body-powered prosthesis rst. Once the individual issuccessfully using the body-powered prosthesis, he or she isevaluated for the more expensive myoelectric system.


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intimacy of the t between the socket and the residuallimb also provide suspension. The harness is composed of a collection of strategically placed straps around the shoul-der or thorax to transmit the force of proximal bodymotion to the prosthetic components. The straps, whichare typically made of Dacron, must be carefully placedand tted so that body power is efciently transmitted tothe active prosthetic components.

A cable system is secured proximally on the harness

In some cases, the preparatory myoelectric ttingphase may begin prior to the completion of the denitivebody-powered prosthesis phase. Approximately 4 to 6months after surgery, the amputee completes the nal stepsof myoelectric prosthesis training.

Harness The harness provides suspension and a way to control theactive parts of the prosthesis. The type of socket and the

Figure 31-5. The amputee is tted with a prosthesis in stages. A. First, a preparatory or provisional prosthesis is fabricated.After a period of prosthetic training and use, the individual is tted with a denitive body-powered prosthesis.B . Denitive left below-elbow prosthesis with a hook but without a cosmetic cover. C . The same prosthesiswith cosmetic glove and hand. D . The denitive prosthesis used for everyday activities.

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and terminates on the TD. There are two basic types: thesingle control system, which typically operates the TD forthe BE amputee; and the dual control system required bythe AE amputee. The amputee transmits muscle tensionalong the stainless-steel cables of the prosthesis to performthe desired motion. For example, in the BE amputee, thecable terminates on the TD. The OT trains the patient toperform coordinated movements of arm exion and shoul-der abduction to operate the TD. The body-powered AEprosthesis uses the same principles but requires a secondcable to control the elbow unit.

PROSTHESES BY LEVEL OF AMPUTATIONPartial Hand ProsthesisA partial hand prosthesis or orthosis is useful only if itincreases function with minimal impairment of sensationand residual hand function or if it improves cosmesis. Typ-ically, a prosthesis is not required to improve function if two or more digits remain. With two remaining digits, aperson is able to adduct or oppose one nger to the other.If opposition is not possible with the remaining digits, arotation osteotomy may be considered in an attempt to

Figure 3 1-6 . Myoelectric prosthesis with a wrist rotator, prosthetic hand, and polyvinyl chloride glove. The rectangularcompartment on the medial aspect of the forearm contains the battery that powers the prosthesis.

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vides a ne tweezer-like grasp but covers part of thesensate residual hand. In addition, this prosthesis is difcultto use overhead (see Fig. 31-7). Because of its appearance,many patients do not accept the partial hand body-powered prosthesis with a hook.

Cosmesis is the number one concern for some indi-viduals with this level of amputation. Personal preference

create opposition. If only the thumb remains, an orthosisthat provides a surface for opposition can be fabricated.

A partial hand amputation weakens grasp. Graspstrength can be improved by tting the person with a pros-thesis with a hook, for example, to assist heavy lifting orother work. The prosthesis is cable driven and the hookprotrudes from the palmar surface of the hand. This pro-

Figure 31-7. Self-contained myoelectrically powered prosthesis with a wrist rotator and Greifer hook. On the medial aspectof the prosthetic forearm there is a panel to access the battery. A functional arm orthosis. A hook is present onthe palm of the hand, as would be needed after a partial hand amputation. Because of the ail upperextremity, chest expansion activates the hook. However, a partial hand amputee would use arm muscles toactivate the hook.

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that allows them to change the TD depending on the situ-ation, for example, cutting the lawn versus going to awedding. If the individual intends to vary the TD, a quickdisconnect wrist is preferred over a friction wrist, which isscrewed onto the prosthesis.

Below-Elbow ProsthesisFor UE amputation the elbow is the point of reference,that is, AE or BE amputation. This terminology is easy tounderstand and readily conveys the same information tothe physician, the therapist, and prosthetist. One canreadily generalize about the upper-extremity functionremaining, the function lost, and the basic prosthetic com-ponents needed. However, terms such as transradial andtranshumeral are more accurate anatomic descriptions andare consistent with terms used for other common levels of

In the conventional body-powered prosthesis, thenumber of rubber bands located at the base of the hookngers determines the grip force of the TD. One rubberband is equivalent to approximately 1lb (0.45kg) of pinchbetween the two hook ngers. By producing tension on thecable, the amputee is able to open or close the hook (Fig.31-12). Though a hook is more functional, the amputeemay reject it for social and cosmetic reasons.

Prosthetic hands are bulkier and more difcult to usethan hooks. Hook TDs provide a more precise grip. Themechanical hand, which is bodypowered, provides only3lb of grip force while a myoelectric hand can provide 25lb (11.25kg). However, both hands appear the same if acosmetic glove is worn over the TD.

Because of the advantages and disadvantages of thehook and the hand, most patients prefer a prosthesis design

Figure 31-9. A, B . This specialized rie-holding terminal device allows this individual to participate in recreational targetshooting. This prosthesis is a preparatory short above-elbow prosthesis.

Figure 31-10. A, B . This terminal device is made specically for holding a golf club.

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amputation, such as WD and transmetacarpal amputation. Though the terms transradial and transhumeral are preferred,the terms above elbow (AE) and below elbow (BE) are wellestablished in the professional literature.

With the loss of the wrist, and possibly forearm rota-tion, the BE amputee needs a wrist substitute. Three basictypes of wrist units are available for conventional prosthe-ses. The rst two types provide pronation and supinationbut not wrist exion and extension. The amputee mustposition the wrist unit in the desired position of pronationor supination. The variable friction wrist unit adjusts forvariable rotation friction, that is, from loose to tight. Mostindividuals prefer the quick-change wrist units because theamputee can change the TD quickly.

The third type, the wrist exion unit, provides notonly variable friction for wrist rotation but also wristexion. This is an important option for the bilateral

amputee, or the person with a nonfunctional contralaterallimb, who is dependent on the prosthesis to do midlineactivities, such as dressing. In the bilateral amputee, thisunit is placed on the dominant upper-extremity prosthesis.Unilateral amputees rarely require this type.

These three units fulll the basic purpose of a wristunit; that is, they act as a site for attaching and positioningthe TD. The wrist units available for the forearm after WDare considerably thinner than the standard wrist unit buttypically do not lend to a quick interchange of TDs.

There are three basic types of elbow hinges: the ex-ible hinges, the rigid hinges, and step-up hinges. In thepresence of a long residual forearm, exible elbow hingesallow natural forearm rotation. Rigid hinges impede thismotion. However, because functional pronation andsupination motions are lost as the residual forearmbecomes shorter, exible hinges become unnecessary. Rigidhinges are a better option for the shorter residual forearmbecause more forearm stability is needed.

The individual with a very short limb after trans-radial amputation can benet from step-up hinges since

Figure 31-11. A variety of tools that are also terminaldevices.

Figure 31-12. This child demonstrates how to use humeralexion to open the terminal device of thebody-powered below-elbow prosthesis.

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clothing. A gure-of-nine harness affords more freedom of motion and is an excellent choice for a BE prosthesis, butusually requires supracondylar suspension as well.

Elbow Disarticulation Prosthesis The person who has undergone ED needs mechanicalreplacement of elbow exion and extension. There is littleroom for a standard prosthetic elbow, however. To avoidmaking the prosthesis too long when compared to theintact upper extremity, an external locking elbow joint isrequired rather than the standard internal locking joint.

These units are less cosmetic and easily damage clothing.However, ED can be a valuable option for the bilateralamputee who must use a residual limb for self-care. ED ispreferred in children to avoid the complication of bonyovergrowth associated with diaphyseal amputations.

Because an ED prosthesis requires the individual tocontrol both elbow and TD functions, a dual type of shoulder harness is needed. Humeral rotation, preservedby disarticulation, is captured by conguring the internaldistal socket with an oval shape and achieving an intimatesocket-limb interface in the region of the humeralcondyles. Only about 50% of available humeral rotation istransmitted to the prosthesis, however.

The physical characteristics of the residual limbinuence the socket design prescribed. For this level of amputation, there are basically three options available:socket with a fenestration or window, a screw-in type of socket, or a socket with supracondylar wedges. Socketswith pneumatic bladders are available. Though used infre-quently, pneumatic bladders are an option for the person

anatomic elbow exion is usually limited to less than 90degrees. These hinges amplify the range of motion (ROM)at the elbow in a ratio of 1: 2. For instance, 50 degrees of elbow exion results in approximately 100 degrees of pros-thetic exion. The step-up hinge design requires that thesocket be a separate unit from the prosthetic forearm (splitsocket design) (Fig. 31-13). Unfortunately, though exion isincreased, the lever arm force is reduced approximately50%. The force applied to the volar surface of the residualforearm is high and many patients do not tolerate the pres-sure. This system is preferred for the amputee with a veryshort residual forearm with limited ROM for whomincreased ROM is more important than strength. Thesehinges can be very useful, particularly for the bilateralupper-extremity amputee.

The distal inner socket in the long BE , or transradial prosthesis , characteristically is at to capture the naturalpronation and supination of the forearm and to transmitthis motion to the TD. The triceps cuff transfers the forcesbetween the socket and the shoulder harness. TheMuenster-type socket often is used in the case of the short BE amputation . It reduces the amount of suspension needed;however, a cable system is still required to operate the TD.

Two basic types of harnesses are available for thepatient who underwent transradial amputation: the gure-of-eight harness and the shoulder harness with a cheststrap. Because the gure-of-eight harness allows for thewidest range of activities with the least restriction, it is themost common harness used by unilateral and bilateralupper-extremity amputees. It is the harness of choice forwomen because there is no chest strap to interfere with

Figure 31-13. A step-up elbow amplies the amount of natural elbow exion in the individual with a very short limb after

below-elbow amputation.

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with a bulbous distal limb or whose limb volume varies

signicantly.Sockets with exible inner liners, like those used forlower-extremity prostheses, are popular among upper-extremity amputees. They are cooler than the standardhard socket. Made of moldable plastics, these liners arethin and accommodate changes in limb shape and volumethat occur with muscle contraction. Many amputees ndthese more comfortable than other sockets.

Above-Elbow Prosthesis The shorter the remaining humerus is, the more thepatient loses rotation, power, and leverage. An amputationat or below the distal third of the humerus affords theamputee many of the advantages of ED, but supracondy-lar suspension and rotation control are lost. Though scapu-lar motion provides some control, humeral motionprovides primary control for the transhumeral prosthesis. Agure-of-eight harness with dual-control design is the mostpopular system.

Transhumeral amputation that is performed at least5cm proximal to the elbow leaves a limb that canaccommodate an internal or inside locking elbow unit (Fig.31-14). The turntable multiple locking elbow unit, which isthe most common unit used by the AE amputee, has 11locking positions. It provides 5 to 135 degrees of exion,whereas the elbow unit used in a disarticulation prosthesishas only seven positions, or fewer if it is a heavy-dutydesign. With a body-powered prosthesis, if the elbow isunlocked, pulling the cable exes the elbow. If howeverthe elbow is locked, a pull on the main cable operates the

TD (48).A residual limb of less than 10cm after transhumeral

amputation can be tted with an AE prosthesis but oftenrequires a forearm spring lift assist incorporated into theelbow unit. The most proximal transhumeral amputation

that results in a functional limb is performed at approxi-mately 5cm distal to the axillary fold. A shorter residuumis unable to control the prosthetic socket effectively (49).

Hybrids of myoelectric and body-powered systemsare very valuable for the AE amputee. A body-poweredelbow with a myoelectric hand is a common choice. Themyoelectric hand, with its stronger grip and gradedcontrol, is valuable for the person whose work or avocationinvolves a lot of holding and stabilizing objects. The myo-electric elbow with a body-powered TD affords moresensory feedback for the patient who needs feedbackregarding TD function.

Shoulder Disarticulation and Forequarter ProstheAt this level of amputation the majority of upperextremityfunction is lost. The patient has little residuum to operate aprosthesis. More mechanical replacement is required tocompensate for the lost hand, wrist, elbow, and shoulderfunction (Fig. 31-15). In general, the individual needs a

TD, wrist rotator, elbow exion-extension unit, and alocking turntable. Passive shoulder positioning is required.Not surprisingly, the prosthetic rejection rate is highestamong these patients. For some persons, this level of pros-thetic replacement represents overgadgetization, that is,more technology than they nd functional or tolerable.

These individuals often opt for a simple passive prosthesisfor aesthetic reasons. Others choose no prosthesis at all.

Figure 31-14. An example of an above-elbow prosthesisbeing used as a functional assist. Note theinternal locking elbow unit with an externallyattached forearm lift assist (spring loaded).

Figure 31-15. Forequarter body-powered prosthesis. The

prosthetic components include a chest strap,detachable shoulder cap, single-controlterminal device cable, passive locking elbow,quick-change wrist, and hook terminaldevice.


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Currently, shoulder units require passive positioning.Basic types include the single-axis joint that allowsonly shoulder abduction, the double-axis unit that providesshoulder exion and abduction, and the four-way frictionshoulder design that allows full passive motion. The shoul-der exion and abduction unit is the most common andmost functional.

Cosmetic ProsthesisFor some patients, cosmesis far outweighs the need ordesire for a functional prosthesis. Some individuals are notable to operate a prosthesis. Often individuals whose upperextremity was amputated at a very proximal level prefer acosmetic prosthesis and do not want a prosthesis withactive components. Individuals with an FQ amputation orSD may do best with a simple shoulder cap to restore theprole of a normal shoulder (Fig. 31-16). The physicianmust know the patient and keep in mind that prescribing aprosthesis is typically a compromise between cosmesis andrestored function. Hybrid systems of passive and active ele-ments, with body-powered and externally powered compo-

nents, are often the best choice.

Depending on the shoulder prole remaining, stabi-lizing a prosthesis can be difcult. Sockets are fabricatedusing plastic laminates. Control of perspiration is moreproblematic than with more distal amputations. The pros-thetist is challenged to achieve an intimate socket-limbinterface to suspend the prosthesis while providing suf-cient ventilation. Moisture-absorbing material placed or

worn under the socket (e.g., cotton T-shirt) helps to controlperspiration. Antiperspirants that control excess perspira-tion and need only to be used once or twice weekly areavailable commercially. The weight of the prosthetic armcreates high pressure over bony prominences. Duringsocket fabrication, sufcient relief must be provided inthese areas to avoid pain and skin breakdown.

Some individuals benet from a prosthetic shoulder joint while others prefer a bulkhead design. With thebulkhead design, the prosthetic humerus is attacheddirectly to the socket and no shoulder motion is provided.Omitting the shoulder unit reduces the weight of theprosthesis, making it very attractive to some amputees. Atthis level, a lightweight endoskeletal prosthesis is also an

option.

Figure 31-16. Forequarter amputation. Individuals who have had an amputation at this level often prefer a simple shouldercap without other prosthetic components. This passive prosthesis restores the shoulder prole, improving thet of clothing, but does not provide additional upper-extremity function.

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PEDIATRIC PROSTHETICSUpper-extremity limb loss in children is most often con-genital. The etiology is highly variant, ranging from mater-nal infection, chemical or drug exposure, and amnioticband syndromes, to single gene mutations. Though somecongenital limb deciencies are associated with known syn-

dromes, for example, craniofacial and thrombocytopeniaabsent radius (TAR) syndromes, or thalidomide exposure,the majority is of unknown etiology. The most commoncongenital limb loss is transverse deciency of the proxi-mal third of the left forearm (Fig. 31-17).

Acquired limb loss accounts for 40% of pediatriclimb loss, typically involving a single limb; 60% involvesthe lower limb. Trauma is the most common cause; tumorand disease are next in frequency. With trauma, the limbloss is primarily due to power tool accidents, burns, andmotor vehicle accidents. In the toddler and preschooler,power tools, such as lawn mowers, and household acci-dents are the primary causes. Regarding surgical amputa-tions for disease, more than half are secondary tomalignant tumors in preadolescents and adolescents.

Over the years, efforts have been made to classifyand describe congenital limb deciencies. Much of the ter-minology, being imprecise and ambiguous, generated con-fusion. The International Organization for Standardization(ISO), involving the work of the International Society forProsthetics and Orthotics (ISPO), has developed a widelyaccepted classication system and standard terminology forcongenital limb deciency. There are two major classica-tions: transverse limb deciencies and longitudinal limbdeciencies. The system is restricted to skeletal absence orreduction and does not consider the etiology or embryol-ogy. Since the classication is restricted to the absence orreduction of normal skeletal elements, radiography, orother methods to identify skeletal elements, is used. Lack of

a skeletal element beyond a certain level is classied as atransverse deciency. The limb has developed normally toa certain level, after which no further skeleton exists dis-tally. In transverse limb deciency, often limb bud rem-nants (often referred to as nubbins ) are present. Thetransverse level is named by the terminal bone and thelevel at which no further skeletal elements exist. All other

limb deciencies are described as longitudinal deciencies,that is, skeletal absence or reduction in the skeletal longaxis of the arm or leg.

The child with a congenital limb deciency is ttedwith a prosthesis in accord with the childs developmentalstage. A child with an upper-extremity deciency can betted with a passive hand prosthesis at 2 to 3 months oldto facilitate the development of hand skills.

Children with partial hand amputations or congeni-tally absent digits are typically not t with a prosthesisbecause of the sensory loss created by the device coveringareas of sensation. Children are very adaptable and func-tion very well without a prosthesis. Often, a prosthesis addslittle function at this level. Like adults, opposition posts and

pads can be used. Acceptance of these devices is variableand often are task specic. A childs acceptance is affectedby the function provided by the device and by the attitudeof parents or caregivers toward the prosthesis or orthosis.

Children with limb deciency or loss at a more prox-imal level benet from a prosthesis, and need to be t at ayoung age before they develop compensatory techniquesthat preclude the use of a prosthesis. If a child has notbeen tted and trained by the age of 2 years, the rejectionrate is signicantly higher than it is for those tted beforeage 2. For the child with a congenital deciency, a prosthe-sis must add function or the child will reject it. In the childwith a traumatic or surgical amputation, the prosthesisprovides both limb replacement and functional restoration.Children are very active and require prostheses that aredurable and functional. Like adults, children who have hadan amputation benet from early prosthetic tting.

Children require frequent retting. A child mayrequire socket modication or replacement to accommo-date limb growth as often as every 3 to 6 months. Many of the previous prosthetic components can be reused in thereplacement prosthesis. The use of multilayered socketsreduces the need for socket replacement as they can beeasily modied to accommodate growth. Removablegrowth liners or exible liners, which are composites of sil-icone and polyethylene, can reduce the frequency of socketreplacement.

Cosmesis is important in pediatrics. Often theappearance of the prosthesis is more important to theparents than it is to the preschool child. Parents want thechild to appear normal, as much for the childs sake astheirs. Once the child enters school, he or she becomesmore concerned about appearance. Children, like adults,want to be accepted by peers and not perceived as differ-ent or odd.

Figure 31-17. Transverse deciency of the proximal part of the left forearm is the most commoncongenital limb deciency.


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some patients need professional psychological assistance.Others thrive on their own.

PRE-PROSTHESIS MANAGEMENTIdeally, one would like to begin prosthetic restoration

and rehabilitation before amputation. However, mostupper-extremity amputations are performed emergently.Generally, there is little time to prepare the individualfor amputation or prosthetic restoration andrehabilitation.

If the surgery is elective, the patient, the physicians,and the rehabilitation team are able to collaborate anddevelop a treatment plan. There is also time to educate thepatient about the level of amputation, preoperative andpostoperative course, functional implications of the ampu-tation, and available prosthetic and rehabilitation options.Additionally, the patient is counseled about phantom painand sensation as well as psychosocial concerns.

Unfortunately, the patient and the members of the

rehabilitation team typically do not meet until aftersurgery. However, patient assessment and education shouldbegin as soon as possible. An initial assessment is per-formed. Information is collected about the individuals pre-amputation functional level, including vocational andrecreational activities, upper-extremity dominance, andpsychosocial situation. The initial assessment, or inventory,begins the process of determining the individuals pros-thetic and rehabilitation needs. An individualized pros-thetic rehabilitation program is initiated, integratingmultiple factors including the status of the residual limb,the patients overall functional status and general health,the persons nancial resources, and the amputees goalsand expectations.

As a rule, ADL training does not begin until aperson receives a prosthesis. If the individual becomesadept doing activities with one hand he or she is less likelyto accept and use a prosthesis. Learning to be one-handedinitially seems an acceptable option. However, after 20 or30 years of performing activities with one hand, individu-als who have not used an upper-extremity prosthesis fre-quently develop cumulative trauma syndromes of the back,neck, and the intact upper-extremity. Bilateral upper-extremity amputees are the exception to the rule. Allefforts should be made to enable these individuals to beginfeeding and performing ADLs as soon as possible, evenbefore a prosthesis is available.

Other rehabilitation issues addressed early afteramputation include wound management, edema and paincontrol, scar management, range of motion of the limb,and upper-extremity strength.

Wound Management The surgical site requires close monitoring until healing iswell established. The surgeon prescribes necessary postoper-

terminal illness, are shock, denial, anger, depression, andacceptance (5355).

Every individual feels a personal loss but the grief felt by the amputee is not directly proportional to the phys-ical extent of limb loss. For example, the salesman who haslost his right hand may perceive the loss as deeply as theelectrical lineman who has lost the entire upper extremity.

The lineman may adjust more easily while the salesmanexperiences more grief because of the appearance of hishand for social greetings, whether at work or socializing. Itis crucial for the rehabilitation team to be aware of theindividuals response to amputation. Peer counselors canhelp the patient realize that there is life after amputa-tion. Referral to mental health professionals, ideallysomeone experienced working with individuals with limbloss, can assist individuals whose grieving exceeds the pa-rameters of normal grief.

Every amputee eventually grieves, but not everyonedoes so at the same rate. Some reach acceptance quickly,while others are still grieving 10 years later. Cliniciansreport that the grief process lasts approximately 2 to 3

years. The individuals past experiences, cultural back-ground, premorbid personality, coping skills, current inter-personal relationships, and support systems impact theindividuals ability to achieve acceptance of the limb loss.Grieving is a dynamic process and may recur. Later events,such as a wedding, may remind the individual of theimpact of the limb loss on personal appearance and lifechoices. Typically, the anger, irritability, and depressionassociated with the loss eventually resolve. Life resumes.

The amputee works, socializes, and plays. The individual isdifferent because of the amputation. The amputee doesnot like it, but it is okay. Life is different but not over. It issomething the individual can live with. Unfortunately,some never reach this level of acceptance.

The amputee is not the only one who grieves. Familyand loved ones also grieve, though less intensely. Children,who experience traumatic loss, tend to move throughthe grief process more quickly than adults. Parents of children with congenital limb deletions feel responsibleand grieve deeply, while the infant is unaware of the de-ciency. However, at a later age, when other children oradults react to the childs limb loss, the child learns thatshe or he is different. The child may grieve and wonderWhy do I have to be different? The experiences of thevarious psychosocial and physical stages of maturationremind the amputee of the impact of limb loss on his orher life.

Limb loss is difcult at any age. Grief is painful.However, normal grief allows the person to adjust to theloss and to progress through rehabilitation to a full andproductive life. The rehabilitation team must acknowledgethe individuals loss and support the individual through theprocess. Direct discussions about limb loss, the personaland social impact, and prosthetic restoration and rehabili-tation assist the amputee in accepting the loss. However,


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externally powered prosthesis.An experienced therapistlistens to the electronics, monitors the speed of movement,and determines if the correct control muscle is utilized(e.g., wrist extensors for opening TD, not closing TD). Inaddition, the therapist checks the mechanical componentsof the prosthesis to determine that they are functioningproperly.

PROSTHETIC TRAININGProsthetic training that focuses on the patient increases thelikelihood that he or she will effectively use the prosthesis.

Typically, patients learn to use the prosthesis by trial anderror once they have been instructed in the specic controlmotions. Not all amputees approach activities using thesame technique. Amputees who are experienced with toolstend to nd training easier than those who are unfamiliarwith tools. The OT acts as a facilitator, encouraging inde-pendent problem solving and providing guidance and assis-tance as needed. Only one therapist should do the trainingor the amputee will become confused by the different

approaches. An experienced therapist who is a strongadvocate of prosthetic use signicantly increases the likeli-hood of successful prosthetic training (41). The amputeewho is not tted with a prosthesis during the 30-daygolden period needs to relearn how to perform activitiesonce the prosthesis is tted. Having to abandon one-handed techniques and relearn prosthetic techniquesreduces the likelihood that the individual will become asuccessful user of the prosthesis.

The individual must have realistic expectationsregarding what the prosthesis can and cannot do. Theamputee must consider the prosthesis as an assist. In aunilateral amputee, the prosthesis assumes the role of anondominant upper extremity for activities. If the amputa-tion involved the individuals dominant hand or arm,the contralateral limb assumes dominance. Typically, bilat-eral amputees use the longer residual limb as the dominantone.

Prosthetic training is divided into three distinctphases: orientation, controls training, and use training.During prosthetic orientation, the patient learns aboutprosthetic components. General instructions in the wearand care of the prosthesis are reviewed. During prostheticcontrols training, the individual learns to operate all pros-thetic components. The amputee must learn to operate thecomponents smoothly and efciently, avoiding strain orawkward movements. During prosthetic use training, theperson learns to perform ADLs with the prosthesis. Bilat-eral tasks, such as cutting with scissors, cutting meat, andtying shoes, are emphasized.

Prosthetic Orientation The patient rst learns how to wear the prosthesis. Typi-cally, the amputee learns to don and doff the prosthesisusing either a pullover technique or a coat technique. The

strength and endurance of muscles, particularly thosemuscles that will operate the prosthesis. This is particularlyimportant in patients with known weakness around theglenohumeral joint and scapula.

PROSTHETIC CHECKOUTWhen the patient receives any prosthesis, preparatory ordenitive, the OT checks the prosthesis to make sure it isjust what the doctor ordered (56). In addition to verify-ing that the prosthesis meets the specications of the pros-thetic prescription, the OT evaluates cosmesis, comfort, t,control efciency, stability of suspension, and the mechani-cal components of the prosthesis. Ideally, the prosthetist ispresent and makes the appropriate modications beforethe amputee takes the prosthesis home (57).

The prosthesis should appear to be the same length,circumference, and shape as the sound extremity. Theprosthesis should not have the same dimensions as the con-tralateral side or it would appear too large and bulky.

Proper length is achieved when the end of the hook or thetip of the prosthetic thumb is level with the tip of the con-tralateral thumb with the arms extended at ones side(5860). Length is important not only for appearance butalso for the most effective use of the TD. For example, if the prosthesis is too long it will interfere with hand-to-mouth activities. The cosmetic glove covering the pros-thetic hand needs to be similar in color to the sound hand.No glove will match the color of the intact hand exactly,but reasonably priced cosmetic gloves that provide a goodmatch are available commercially.

Comfort is a major issue. The amputee will not weara prosthesis that causes pain. The socket should provideeven pressure on the residual limb. Pressure should beeliminated or reduced at bony prominences or neuromasites. The socket should not leave red skin marks that lastmore than 15 to 20 minutes after removal of the prosthe-sis. Skin irritation, breakdown, or pain suggests an unsatis-factory t. Modication of the socket t or suspensionsystem usually corrects these problems.

The prosthesis should permit maximal active ROMof the residual limb. Often this is not feasible with a veryshort residual forearm or Muenster-style sockets(41,6163). Though harnessing systems may preclude fullshoulder exion or abduction, active shoulder exionshould be no less than 90 degrees (41).

The mechanical efciency of the control system of abody-powered prosthesis is evaluated. Stable suspension of the prosthesis is also crucial. With a 25-kg axial load (i.e.,50lb or one-third of the body weight of a child), theamount of socket displacement on the residual limb shouldnot exceed more than approximately 2.5cm (41,6163). If the socket migrates more than 2.5cm, the harness needsmodication.

The checkout procedure is slightly different for the


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amputee initially wears the new prosthesis for periods of 30 to 60 minutes, and then gradually increases the wearingtime. Within 1 or 2 weeks, the amputee should be comfort-ably wearing the prosthesis for an entire day. Newamputees continue to wear shrinker socks or elasticizedwraps when not wearing the prosthesis. This is requireduntil the volume of the residual limb stabilizes, or inde-

nitely in patients with uctuating limb volumes. The wearer of a conventional, or body-powered,prosthesis is taught how many socks to wear and the indi-cations for changing the number of socks. The amputeemust learn how many rubber bands to put on the VOhook. Typically, the individual begins with about 1lb(0.5kg) of pressure, as measured by the pinchometer. Thenumber of rubber bands is gradually increased until suf-cient pressure is provided to meet the amputees functionalneeds, that is, 3 to 15lb (1.356.75kg) of pressure. Gener-ally, BE amputees need approximately 8lb (3.6kg) of pinchforce, while AE amputees develop about 5lb (2.25kg) of pinch force with the VO hook.

The amputee is able to communicate effectively with

the team once he or she learns to identify basic prostheticcomponents (64). Basic prosthetic concepts should be intro-duced as well. The prosthetic rehabilitation team, on theother hand, must learn to discuss aspects of prostheticrestoration and rehabilitation in lay terms.

Since many amputees require more that one TD,they must learn to switch from one TD to another and theindications for the various TDs. Users of conventionalprostheses often learn to change cables and adjust theharness to improve control.

It is important for amputees to learn to care for limbsocks, sockets, harnesses, cables, TDs, rubber bands, cos-metic gloves, and batteries. They are taught auditory andvisual clues that indicate malfunction or deterioration.Amputees are to contact the prosthetist as soon as a mal-function is detected, to prevent further damage.

Conventional Prosthesis Controls Training The patient learns the proper body mechanics andmotions to operate all prosthetic components. Eventually,the amputee will perform the appropriate motions auto-matically. For most amputees, basic controls training isaccomplished in 30 minutes.

Basic Controls Training There are two parts to basic controls training: opening andclosing the TD and learning to preposition it.

Opening and Closing the Terminal Device

The patient learns to open and close the TD and to acti-vate the TD with the elbow and shoulder in different posi-tions, including full exion and full extension. For instance,the amputee learns to activate the TD using the controlmotions of humeral exion, biscapular abduction, orshoulder depression.

Prepositioning the Terminal Device The person learns to strategically place the TD in aposition to grasp the object most easily. Using the soundhand, the unilateral amputee passively pronates orsupinates the TD into the desired position. Next, thestationary nger of the hook or hand touches the objectand the movable hook or ngers grasp the object. To

position the TD, the bilateral amputee uses the other TDs or pushes the TD against the body or a stable object,such as the edge of a table. The friction wrist should betight enough to maintain the hook or hand in positionwhen the cable is activated. The bilateral amputee with awrist exion unit learns to position the unit and the TDclose to the body, for activities such as toileting, eating, andshaving.

Above-Elbow Controls Training In addition to the above-mentioned techniques, the AEamputee learns additional control techniques. Typically, anadditional 30 minutes of training is necessary to learnthese skills.

Elbow Flexion and Extension The patient learns how to activate elbow exion. With theelbow unlocked, the patient learns that humeralexion causes the prosthetic elbow to ex. This is thesame motion that operates the TD if the elbow unit islocked.

Elbow Locking Mechanism The AE amputee learns to activate a second control cablefor locking and unlocking the internally or externallyhinged elbow. The amputee learns to use elbow nudging tolock and unlock the elbow hinges. Sometimes, this is a dif-cult motion to learn. This motion, often described asdown, back, and out, combines humeral extension andabduction with scapular downward rotation and depressionto control the elbow hinges (48). There are other controlmotions for activating the elbow cable. Some prosthetistsdesign the cable so it goes through a pulley on the shoul-der saddle and then attaches to a belt loop. Shoulder ele-vation activates this system. The patient learns to listen forthe clicking sounds made by the elbow locking cable as acue to verify that the elbow lock is on or off. Elbow lockingin various degrees of elbow exion and extension is alsolearned.

Humeral TurntableAE amputees who lack 5cm or more of humeral lengthbenet from a humeral turntable. The humeral turntable,located just proximal to the internal locking prostheticelbow, requires passive prepositioning into the appropriateamount of internal or external rotation. The turntablemust be tightened enough so that the selected position ismaintained when the TD is activated.


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sors, while AE amputees learn to isolate the biceps andtriceps. Some myoelectric systems are proportionally con-trolled; that is, the greater the muscle contraction, thefaster the TD reacts or the greater the grip force produced.Amputees must learn to use proportional controls appro-priately. Greater speed and more force do not translateinto more control.

Amputees who are t with the myoelectric AE pros-theses often need to learn to perform quick co-contractionsof the biceps and triceps to switch control between theelbow and hand. The prosthesis is in a hand mode exceptwhen co-contraction is used to switch it to the elbowmode. Like the TD, the elbow is controlled by the bicepsand triceps. If the elbow is held in the same position for abrief period of time, the elbow automatically locks and theprosthesis automatically switches back to the hand mode.

Single-site electrodes are available for the individualwho does not have two acceptable control sites or cannotisolate muscle contractions. In this case, the patient istaught to create a quick muscle contraction for one pros-thetic action and a slow muscle contraction for another.

This same control concept is used for activating poweredwrist rotators.

Switch-Control Training When myoelectric control sites are not available, other pos-sible control motions (e.g., those that activate an on-off rocker, button, or pull switch) are considered. Thesecontrol motions are usually proximal movements that arenot used for normal ADLs, such as shoulder elevation. Asmentioned earlier, chin nudge switches are occasionallyused. Most of the controls training for this type of external power is conducted after the individual receivesthe prosthesis.

Shoulder Disarticulation and Forequart erControls Training Control Motion

Typically, these individuals use chest expansion to activatethe cable for TD use. This strap attaches both anteriorlyand posteriorly to the prosthetic socket. Full cable excur-

sion is often an unrealistic goal, and as a result, full volun-tary TD opening is not achieved. Often the amputee isunable to provide sufcient strength to utilize a body-powered prosthesis and nds it is more work than it isworth. For these individuals, externally powered compo-nents may be a good option.

Four-Way Friction Shoulder HingeIf the patient chooses to have a shoulder unit, this type is afrequent choice. The patient is taught how to passively(manually) preposition the prosthetic arm in humeralexion or extension, adduction or abduction, or anycombination.

Nudge Control This button or lever mechanism is on the thoracic shelland enables the individual to engage or disengage theelbow lock. Typically, the amputee uses the chin to operatethe nudge control. The individual passively positions theelbow into the position appropriate for the task and locksit. This option is selected when other motions are notavailable to control the prosthesis.

Externally Powered Controls TrainingMyoelectric Site Selection and Training Controls training for the myoelectric prosthesis is begunbefore the patient is tted with the prosthesis. Selectionand training of appropriate control sites is most important.An experienced therapist or prosthetist is essential to suc-cessful training (57).

The amputee must be able to generate sufcientmuscle contraction to activate the myoelectric sensor con-tained in the prosthesis. Possible myoelectric control sitesare tested using an electronic biofeedback system or a myo-electric tester that provides quantication of the electricalpotential generated by the selected muscle site (Fig. 31-19).

The most distal site with the strongest signal is chosen. Asa rule, muscles that approximate normal motion areselected. For instance, wrist exors and extensors areselected to close and open the TD of the BE prosthesis.

Control of muscle site signals is the basis of success-ful myoelectric prosthesis use. Dual-site control is preferredover the more difcult single-site control. With dual-sitecontrol, two muscles must be able to generate indepen-dently a sufcient electrical potential to operate the pros-thesis without interfering with each other. Typically, thepatient is taught to isolate antagonist muscles. For example,BE amputees learn to isolate the wrist exors and exten-

Figure 31-19. Electromyographic site selection and controlevaluation are performed in preparation fortting a myoelectric prosthesis.


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amputee include rocker knives, cutting boards, or scrubbrushes with suction cups to stabilize the object. Unilateralamputees may require turning knobs afxed to the steeringwheel for turning when driving an automobile.

Bilateral Amputees Persons with bilateral BE amputation can become com-

pletely independent in ADLs (Fig. 31-22). However, learn-ing to do overhead activities is difcult. Individuals withbilateral amputations may require driving rings, buttonhooks, lever-type doorknobs, or ring pulls for zippers toachieve independence.

In addition to AE prosthetic training, children withcongenital bilateral AE limb deciencies should learn touse their feet as they would hands. These amputees fre-quently require a bidet for toileting. Telephones with aspeaker phone work well for these individuals. Certainactivities (e.g., dressing above the waist or cutting meat) areextremely challenging. Typically, these individuals, andamputees with more limb loss, require assistance fromanother person at various times during the day for certain

activities such as bathing.Amputees with bilateral SD or higher limb loss ndit very difcult to don and doff prostheses independently

Figure 31-22. The occupational therapist trains an amputeeto use the prosthesis to perform activities of daily living (ADLs).

Figure 31-21. The individual with upper-extremity loss canlearn to perform activities necessary forschool or work.

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(48). They

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