Advantages and Limitations of Shelf Acetabuloplasty for Dysplastic Osteoarthritis of the Hip

We retrospectively reviewed 47 hips with symptomatic acetabular dysplasia treated with shelf acetabuloplasty. The mean follow-up period was 17 years with a minimum of 5 years. Ten hips (21%) had been converted to total hip arthroplasty (THA) at a mean of 18.2 years. Survival analysis using conversion to THA as an endpoint showed survival rate of 97.8% at 10 years and 78% at 20 years. Forty hips without preoperative joint space narrowing had a survival rate of 90% at 20 years postoperatively. This was significantly higher (p < 0.01) than that of seven hips with joint space narrowing, which was 29% at 20 years. In 27 hips from patients aged <35 years at operation, the survival rate was 95% at 20 years. This was significantly higher (p = 0.00761) than the survival rate of 55% at 20 years in 20 hips from patients aged ≥35 years.