Cone femoral prosthesis for osteoarthritis of the hip with femoral dysplasia.

PURPOSE To assess the clinical and radiological outcomes of total hip replacement (THR) using the cone femoral prosthesis. METHODS Four men and 15 women (26 hips) aged 19 to 78 (mean, 45) years underwent THR for osteoarthritis of the hip with femoral dysplasia using the cone femoral prosthesis. Only 17 patients (24 hips) were available for review. Pain and functional limitation were assessed using the Oxford hip score. Stable fixation by bone ingrowth was defined as no subsidence or radiolucent lines around the prosthesis. RESULTS The mean follow-up duration was 50 (range, 25-92) months. The mean Oxford hip score improved from 44 (range, 32-54) preoperatively to 17 (range, 12-28) at the latest follow-up. Prosthesis survival was 100%. All prostheses showed stable integration with bony ingrowth and no measurable subsidence. 15 hips had excessive anteversion of 25 to 90 degrees. No patient had venous thromboembolism, deep prosthetic infections or dislocations. CONCLUSION The cone prosthesis is less complex and expensive than the modular prosthesis. The early functional and radiological outcomes were excellent, with marked improvement in pain and function. This constitutes effective treatment for osteoarthritis of the hip with femoral dysplasia.