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CHAPTER 30
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The Child with a Limb Deficiency
foot in the best mechanical position. Children who have mild
equinus contractures of 30 degrees or less will usually stretch
these out with prosthetic use and do not need special atten-
tion preoperatively. Crutch training should be done preop-
eratively, as in all elective surgery that will require crutch use
postoperatively.
The improvement in function with the rotationplasty,
compared to other procedures, has been documented both
for patients with tumor (181–183) and for those with PFFD
(178, 184). These studies demonstrate patients with rotation-
plasty function better than those with knee arthrodesis and
foot ablation, not quite so well as those with a below-knee
amputation, and not as well as those who have rotationplasty
for noncongenital conditions, for example, tumor. Those
with rotationplasty for noncongenital conditions probably
do better because of the normal hip function that remains
one of the major problems in those with PFFD.
Limb Lengthening.
The general concepts surrounding limb
lengthening are covered in other chapters. Several issues spe-
cific to limb lengthening in patients with congenital short
femur are worthy of discussion. Issues concerning knee insta-
bility during lengthening were previously discussed in the sec-
tion on fibular longitudinal deficiency.
Stabilization of the Hip.
Most patients with PFFD, whether
undergoing lengthening or prosthetic fitting, will have hip
instability. This is not only because of the deficient bony anat-
omy, but also because of the deficient musculature. This has
resulted in some controversy about the value of surgical proce-
dures to stabilize the hip. Some feel that nothing of functional
value is gained and surgical intervention is not warranted (165,
171, 185), whereas others feel that surgical correction can be
of value (32, 163, 186, 187). It is the authors’ opinion that
in Aitken class A and B patients who have a mobile femoral
head within the acetabulum, surgical correction of an existing
pseudarthrosis with correction of the varus and retroversion
deformity if there is less than a 110 degree neck-shaft angle is
beneficial (Fig. 30-26B–D).
There are multiple anatomic problems to consider: the
pseudarthrosis and consequent malalignment, the flexion/
abduction/external rotation soft-tissue contracture, and the
bony stability of the femoral–pelvic articulation. In those
patients for whom lengthening is planned, it is necessary to
obtain good containment of the femoral head, which may
require an acetabular procedure. In contrast to the typi-
cal anterolateral acetabular deficiency as seen in DDH, the
acetabulum is often retroverted in PFFD, resulting in a lack
of posterior and lateral coverage (188). Therefore, reshaping
acetabular procedures must address this posterior deficiency. In
addition, femoral retroversion and varus are also usually pres-
ent and should be corrected prior to lengthening. The soft-
tissue contractures include the hip flexors (predominantly the
rectus femoris and iliopsoas) and hip abductors (primarily the
gluteus medius and minimus). These may be addressed as part
of the proximal femoral reconstruction as described by Paley
et al. Alternatively, the proximal femoral reconstruction may
be performed without addressing the soft-tissue contractures.
Anecdotally, the soft-tissue contractures may stretch out over
time with prosthetic use, although there is insufficient litera-
ture to advocate one approach over another.
In patients with Aitken class B PFFD, there will be a
pseudarthrosis of the femoral neck. This can be repaired while,
at the same time, restoring more normal alignment. It may not
be necessary to wait until complete ossification of the femoral
neck to perform this procedure (189). Ossification may accel-
erate after realignment.
Iliofemoral Arthrodesis.
There are two types of iliofemo-
ral arthrodeses described. These procedures are an attempt
to address the problem of hip instability predominantly in
patients with Aitken class D femoral deficiency.
In 1987, Steel (190) described arthrodesis of the distal
femoral segment to the pelvis in the region of the acetabulum
in four patients. The femur was fused in 90 degrees of flexion
so that it was perpendicular to the axis of the body. This results
in knee extension being equivalent to hip flexion, and knee
flexion being equivalent to hip extension.
More recently, Brown (191) has described a rotationplasty
in conjunction with iliofemoral arthrodesis. In this procedure,
the distal end of the femur is rotated 180 degrees before it is
joined to the ilium with its axis in line with that of the body.
The knee now functions as the hip joint, and the ankle now
functions as the knee joint, as in a Van Nes rotationplasty
(Fig. 30-36). In his opinion, the complication of derotation was
less likely in these patients than with the Van Nes procedure.
FIGURE 30-36.
AP pelvis radiograph of a patient with PFFD who
underwent 180 degree rotation and fusion of the proximal femoral
segment to the ilium (as described by Brown KL. Resection, rotation-
plasty, and femoropelvic arthrodesis in severe congenital femoral defi-
ciency. A report of the surgical technique and three cases).
