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CHAPTER 30
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The Child with a Limb Deficiency
traditional scanogram radiographs can overestimate the
amount of shortening. Scanograms should be obtained in the
lateral position, which will account for any flexion deformity
at the hip (or knee) in these patients.
For patients where knee fusion and foot ablation is the
treatment plan, an accurate prediction of femoral and tibial
segment length at maturity will help the surgeon decide if the
distal femoral and/or proximal tibial epiphysis and physis need
to be removed at the same time. If one (or both) physes about
the knee are removed at surgery, the physician should counsel
the family that the residual limb will appear “too long” imme-
diately after surgery, but that the normal limb will overgrow
the residual one with subsequent growth.
With regard to the hip flexion, abduction, and external
rotation deformity seen in these patients, the authors experi-
ence is that the deformity resolves after knee fusion and foot
ablation with prosthetic use over several months. Therefore,
when performing knee fusion, the tibia should be fused in line
with the femur rather than in a flexed, adducted, internally
rotated position to compensate for the proximal femoral seg-
ment alignment. The authors do not have experience with
concurrent soft-tissue release at the time of osteotomy (so-
called “super-hip” procedure).
Complications.
Progressive hip subluxation and frank dis-
location can occur with femoral lengthening. Prevention of
this complication is the best treatment. Careful evaluation of
the hip should be undertaken prior to femoral lengthening, if
it is to be performed. Hip dysplasia should be addressed prior
to lengthening with appropriate acetabular reorientation or
augmentation procedures.
As mentioned previously, insufficient or recurrent rota-
tion can occur after Van Nes rotationplasty. Treatment of this
problem is with repeat tibial rotational osteotomy.
Congenital Deficiencies of the Upper
Extremity
Definition and Classification.
If upper extremity defi-
ciencies were completely discussed like lower extremity deficien-
cies, the list of topics covered in this section would be much
larger. Longitudinal deficiencies in the upper extremity include
radial and ulnar longitudinal deficiencies, as well as symbrachy-
dactyly and cleft-hand deformity. Thumb hypoplasia or aplasia
might also be listed. In contradistinction to the lower extremity,
the shortening which results from these longitudinal deficiencies
is rarely the primary clinical problem as it is in the lower extrem-
ity. In reality, pediatric hand and upper extremity surgeons
participate in multidisciplinary team clinics to care for these
patients (much like pediatric orthopaedic surgeons participate
in multidisciplinary team limb-deficiency clinics), and surgical
reconstructive treatment of these patients is best described in
chapters dedicated to the care of these specific disorders. Often,
it is the patient with terminal deficiencies of the upper extremity
that are treated in limb-deficiency clinics, are often candidates
for prosthetic use, and are the focus of this section. The child
with an upper extremity amputation has an inherently different
disability than the child with a lower extremity amputation. The
importance of sensation in the hand, which is seen as the termi-
nal “working end” of the entire upper extremity, cannot be over-
emphasized. Without sensory feedback, the child with an upper
extremity limb deficiency must look at the prosthetic hand to
help it function. In addition, the child must think actively to
control the terminal device of an upper extremity prosthesis.
Both of these factors make upper extremity prostheses much less
efficient and much more difficult to use than a lower extremity
prosthesis. At best, any upper extremity prosthesis will be used
more as an assisting limb rather than as a substitute capable of
achieving bimanual function.
Additionally, upper extremity amputations are very visi-
ble. Unlike the child with a below-knee amputation who walks
without a limp, has a prosthesis hidden under clothes, and can
often match his or her peers in physical activity, the child with
an upper extremity amputation is more easily seen as differ-
ent. For both of these reasons, many patients with transverse
upper extremity deficiencies will not be well served by pros-
thetic prescription. If the prosthesis does not afford the child a
functional gain or cosmetic benefit, he or she will be quick to
reject it. The reasons for some children becoming good users of
a prosthesis, whereas others with the same characteristics reject
it, are not well understood. Although the age at initial pros-
thetic fitting, as well as the parents’ acceptance and compliance
are important, this is not the whole answer. The incredible
ability of the young child to learn to use one hand assisted by
the residual limb with minimal concession to activities that are
assumed to require two hands must also be a significant factor.
Quantification of successful upper extremity prosthetic
use is very patient specific. The number of hours a prosthesis
is used per day is not a good criterion. Many children will use
the prosthesis for specific tasks (riding a bike) while preferring
to remove it for others (swimming). Some children will wear
and use it every day in school, but will wear it very little during
the summer while playing.
What the child can do with the prosthesis when asked and
what he or she actually does with it in the course of a normal
day can be very different. Although some children develop an
amazing facility with the prosthesis in their everyday activities,
many will demonstrate their skill with the prosthesis only in the
medical setting, preferring to use the prosthesis much like their
residual limb during daily activities. Standardized tests have
been developed to measure spontaneous use versus voluntary
control as it relates to age-appropriate activities. The University
of New Brunswick test of myoelectric control is used by thera-
pists to assess the child’s ability to use the prosthesis in a con-
trolled situation. The Prosthetic Upper Extremity Functional
Index is a self-reported measure of the child’s functional abili-
ties during daily activities. The Unilateral Below Elbow test is
an observed functional evaluation instrument that examines
both completion of specific tasks and how the prosthesis was
used in that task. James et al. found that, when evaluating uni-
lateral below-elbow amputees with and without a prosthesis,
