Background: Total hip arthroplasty in patients with unilateral
congenital high dislocation of the hip (Crowe type IV) presents many
challenges, including the problem of a marked limb-length discrepancy. The
purpose of this retrospective study was to analyze the results of total hip
replacement with limb-length equalization in these patients.
Methods: From 1988 to 1996, fifty-six patients (forty-seven women
and nine men) with unilateral Crowe type-IV dislocation of the hip were
treated with a cementless total hip arthroplasty at a mean age of 35.4 years.
The preoperative limb-length discrepancy averaged 4.9 cm. Prior to the total
hip arthroplasty, forty-eight patients with a limb-length discrepancy of
>4.0 cm underwent iliofemoral distraction with use of an external fixator
for eight to seventeen days. The acetabular cup was placed in the anatomical
position in every patient. Shortening femoral osteotomies were not
Results: The iliac fixator pins loosened in six patients. No patient
had a pin-site infection, hip joint infection, or nerve palsy. At the time of
follow-up, at an average of 147.2 months, the Harris hip score averaged 90.2
points. Overall, the mean lengthening after the total hip arthroplasty was 4.6
cm. There were no revisions of the femoral stem. Nine cups were revised, four
because of polyethylene wear and five because of loosening.
Conclusions: We were able to safely place the acetabular cup at the
anatomical position without femoral shortening by bringing the femoral head to
the normal level preoperatively; thus, we could restore nearly normal limb
length. We believe that our twelve-year results are similar to those of total
hip arthroplasty in patients without dysplasia.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.