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CHAPTER 30
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The Child with a Limb Deficiency
recommended against the Brown procedure in cases of com-
plete absence of the tibia.
In patients with Jones type 1b tibial deficiency, it is
important to monitor the patient over time, both for ossifica-
tion of the proximal tibial remnant and to verify good active
extension. It is possible that this remnant will be present, but
good active extension will be absent or the remnant will not
ossify. If there is active extension in a child, but the remnant
is not sufficiently ossified by 1 year of age, the surgeon has
several choices. The patient may be fitted with an extension-
type prosthesis that accommodates the current foot position.
Although this prosthesis (or prosthosis) is cosmetically unap-
pealing, the child is usually quite functional. Alternatively, the
surgeon may attempt to transfer the fibula to the unossified
tibial segment with the goal of obtaining a successful tibial/
fibular synostosis. Lastly, the physician can perform a Syme or
modified Boyd amputation, fit with a prosthesis, and wait for
ossification before performing the transfer.
In the rare patient with type Ia tibial deformity and proxi-
mal femoral deficiency with a very short limb, the best option
may be to arthrodese the fibula to the distal end of the femur.
The goal of this procedure is to increase the lever arm of the
femoral segment, for the same reasons that a knee fusion is
performed in children with PFFD.
In Jones type 2 deficiencies, the treatment of choice
is to create a synostosis between the existing fibula and the
tibial remnant to increase the length of the lever arm. A
Syme or modified Boyd amputation, where the calcaneus is
fused to the distal fibula instead of the tibia, is performed
at the same time, and the patient is fit with a BK prosthesis
(Fig. 30-24). Whether the synostosis is performed side-to-side
or end-to-end, it is important to achieve good alignment of
the fibula in relation to the knee joint. The residual proximal
FIGURE 30-24.
A,B
: Pre- and postoperative lateral radiographs of
a patient with type 2 tibial deficiency. The patient has undergone an
end-to-end synostosis of the tibia and fibula with proximal fibular
resection and a modified Boyd amputation with fusion of the calca-
neus to the distal fibula.
fibula should be removed to avoid problems later with pros-
thetic fit.
Type 3 deficiencies of Jones are very unusual, and there is
not much published experience. Jones et al. reported one case
that was bilateral (148). They described a cartilaginous por-
tion of the tibia, proximal to the ossified portion, which was
“under voluntary muscle control.” Their patient was treated
with excision of the proximal fibula and Syme amputation.
Fernandez-Palazzi et al. (127) had two cases in their report.
Both were treated with Syme amputation, implying that there
was an active quadriceps mechanism.
Jones type 4 deficiency presents a unique problem. At
birth, the foot is deformed, often appearing like a clubfoot to
the inexperienced. In addition, the amount of tibial shortening
that will result is not apparent. This all makes it difficult for the
parents to accept amputation. The difficulty for the surgeon
is that this deformity is a spectrum of deformity. Garbarino
et al. (149) have emphasized the distinction between a short
tibia with a varus foot and a true congenital diastasis of the
ankle joint. The former is usually amenable to reconstruction
according to Schoenecker (131), whereas the true type 4 defi-
ciency with diastasis of the ankle joint usually is treated with
amputation (148, 150).
There are reports of reconstruction for the type 4 deficien-
cies, but in general the follow-up is short and the problems of
a plantigrade foot and limb-length discrepancy are just begin-
ning in these patients (149, 151–153). One patient followed
up to the age of 15 years is described as having satisfactory
ankle function and 6.5 cm of shortening (154), while another
followed up to the age of 10 years (6 years after reconstructive
surgery) is reported as having a stable ankle and plantigrade
foot, but projected limb-length discrepancy is not mentioned
(155). Choi et al. have recently reported on three patients
treated with foot deformity correction with an Ilizarov device
followed by distal tibial/fibular synostosis to stabilize the ankle
mortise. This was followed with limb lengthening, includ-
ing differential lengthening of the tibia and fibula. At skeletal
maturity, all three had a plantigrade foot, less than a 3-cm leg-
length discrepancy and were able to participate in group games
or sports (156).
In their review of tibial deficiencies, Schoenecker et al.
(130) reported on 10 patients with Jones type 4 deficiencies,
of which nine had initial reconstruction of the foot. A Syme
amputation was subsequently done in six of them, usually at
the parents’ request. Of the four patients who retained the
foot, two had contralateral deficiencies in which the prosthesis
accommodated the length discrepancy. One had a lengthening
of 4.6 cm and one remained 4.8 cm short.
From the available information, it seems reasonable to
attempt to retain the foot, if the deformity is at the less severe
end of the spectrum, or if there is a significant contralateral
deficiency. In most other cases, Syme amputation seems most
reasonable.
Prosthetic Management.
Depending on the severity of the
anomaly and the surgery performed, there are several
