CHAPTER 30
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The Child with a Limb Deficiency
1587
Partial-foot Prosthesis.
The most important consider-
ation in the fitting of the partial-foot amputee is to ensure that
adequate load-bearing is designed into the prosthesis of choice.
As a general rule, the more proximal the level of amputation,
the higher the prosthesis must fit over the ankle complex and
the more proximally it must fit on the tibia and fibula. Tissue
condition, function of the remaining foot complex, and activ-
ity of the child all play a role in determining the prescription
and design of the prosthesis.
Complete or partial absence of the toes usually requires
little more than a shoe filler. A carbon fiber insert to better
control forces from heel to toe-off may be incorporated in the
shoe filler. In the case of the very young child, no interven-
tion may be required until a need has been demonstrated, for
example, the inability to keep the shoe on, especially when the
child becomes more active in sports.
The prosthesis most commonly used for the moderate/
short partial-foot amputee is the Lange silicone partial-foot
prosthesis (Fig. 30-53). This incorporates a cosmetic foot shell,
silicone-laminated socket with modified foot sole, and a pos-
terior zipper for ease of donning and doffing. The prosthesis is
fabricated over a modified model of the patient’s partial foot.
The socket trim line is proximal to the malleoli and is fitted
intimately to ensure adequate control. The design of a partial-
foot prosthesis may also include a removable insert, to accom-
modate the need for corrective alignment of the residual foot.
The prosthesis is then cosmetically finished to resemble the
contralateral limb. Overall, this type of prosthesis is perfectly
suited for the child amputee and resists premature wear and
tear. If needed, a partial-foot prosthesis should be prescribed
once the child is pulling to furniture, so that foot control will
begin at an early age. It should be noted that a low-profile
insert (distal to the malleoli), used in conjunction with a high-
top boot, will offer adequate function and cosmesis until a
lower cut shoe is requested by the parent.
The Chopart, or midtarsal, amputation is rarely used except
in special instances (230). In the Chopart partial-foot amputa-
tion level, the prosthesis is modified to encompass the calcaneus
and talus, and this results in a prosthesis that is often longer
than the contralateral limb. The prosthesis must encompass the
ankle joint, and it often rises proximally to the patellar tendon
in an effort to reduce forces on the tibial crest–socket interface.
Selection of prosthetic feet is compromised because of the lack
of space distally, and commercially available carbon foot plates
require permanent attachment with vulcanizing rubber cement.
This negates any changes caused by growth, and realignment to
compensate for gait changes is virtually impossible.
Terminal Devices for the Upper Extremity.
The
choices left open to the prosthetist are numerous and, at times,
controversial. Where some clinics maintain rigid protocols for
terminal device selection, other clinics rely more on patient and
parent input, combined with historic success rates for device
types. Clinics that maintain very high caseloads for myoelectric
devices, for example, will most likely have far more experience
in fitting externally powered prostheses, compared to a clinic
that may only see a handful of potential myoelectric candidates.
In simple terms, the terminal devices can be divided into
hands and hooks, and they can be body powered (cable and
harness) or externally powered (electric). Hands and hooks can
be either voluntary opening or voluntary closing. Patton lists
the functional and prescription criteria for the various terminal
devices (203).
The initial fitting of a child with upper extremity limb
deficiency begins at 4 months of age in a passive prosthesis with
a stylized passive hand. There are several hands manufactured
for this age range (Fig. 30-54A). This allows for equal arm
lengths for the development of propping up on the amputated
side and greater acceptance by the parents. Following initial sit-
ting balance, the clenched-fist terminal device is exchanged for
a small infant passive hand. When the infant begins to reach
out (at
∼
15 to 18 months of age), the clinic team begins to
assess the need for either body-powered or externally pow-
ered prostheses. If body-powered prosthesis is recommended,
a cable-operated Hosmer 12P plastic-covered hook
(Fig. 30-54B) or an ADEPT infant hand (Fig. 30-54C) will be
A
B
FIGURE 30-53.
A
: The Lange silicone partial-foot prosthesis is a custom-made prosthesis that can incorporate a keel to aid in
foot stability and push-off in gait.
B
: It is useful for children with partial amputations of the foot or congenital longitudinal defi-
ciencies of the foot, shown here. It is not useful in feet with insufficient length, for example, those with the Chopart amputation.
