Long-term survival of the acetabular component after total hip arthroplasty with cement in patients with developmental dysplasia of the hip.

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.