Total hip arthroplasty performed without cement in patients with femoral head osteonecrosis who are less than 50 years old

Seventy-two cementless total hip arthroplasties were performed by a single surgeon in 58 patients with the diagnosis of femoral head osteonecrosis. Al l patients were less than 50 years old (mean, 37 years). The mean follow-up was 84 months with a minimum of 48 months. Good-to-excellent results were maintained at final follow-up in 94% of the hips. Revision rate was 1.5% ea ch for the cups and the stems. Mechanical failure rate was 7.6% for the cup s, and 6% for the stems. If the results were analyzed excluding the data fr om the group of patients who received the Mittelmeier prostheses, the mecha nical failure rates for the cups was 0% and for the stems was 4.2%. The pro bability of survival for the entire series using revision as the endpoint w as 96.9% at 11 years. Survival probability decreased to 88.5% if radiograph ic failures were included. Excluding the Mittelmeier prostheses, survival p robability was estimated to be 100% for the cups using both revision and ra diographic failures as endpoints; for the stems, the survival probability w as 98.0% using revision as the endpoint and 95.8% including radiographic fa ilures. Femoral osteolysis was observed in 1.5% of the hips. No hip had ace tabular osteolysis. No measurements of polyethylene wear were attempted in this study. These results appeared superior to total hip arthroplasties don e with early cementing techniques in this population of young patients with femoral head osteonecrosis.