Background: Total hip arthroplasty with cement remains a difficult
procedure in patients with osteoarthritis secondary to developmental dysplasia
of the hip as it is associated with high rates of aseptic loosening of the
acetabular component. The purpose of the present study was to evaluate the
rate of revision of the acetabular component in this group of patients and the
variables that are associated with it.
Methods: We retrospectively reviewed the records and radiographs of
292 hips in 206 patients who had undergone total hip arthroplasty with cement
for the treatment of osteoarthritis secondary to developmental dysplasia of
the hip. The average age of the patients at the time of the index procedure
was 42.6 years, and the average duration of follow-up was 15.7 years (range,
2.2 to 31.2 years). Fourteen patients were lost to follow-up, and seven
patients died from causes unrelated to surgery. A 22.25-mm head was used in
all cases, and bone-grafting of the acetabulum was performed in forty-eight
hips. Survival of the acetabular component was calculated with revision for
aseptic loosening as the end point. Individual survival rates based on age,
component type, previous surgery, and annual polyethylene wear also were
calculated.
Results: The most common reason for revision was aseptic loosening
of the acetabular component, which led to 87.2% of the revision procedures.
The overall rate of survival of the acetabular component was 90.6% at ten
years and 63% at twenty years. A higher rate of acetabular revision was noted
in association with previous acetabular surgery, the offset-bore cup, younger
age, and accelerated polyethylene wear (p < 0.05 for all comparisons).
Conclusions: Aseptic loosening of the acetabular component affects
the longevity of total hip replacements in patients with osteoarthritis
secondary to developmental dysplasia of the hip. The present study identified
the risk factors associated with the long-term survival of the acetabular
component in this group of patients.
Level of Evidence: Prognostic Level II. See Instructions
to Authors for a complete description of levels of evidence.