The Madreporic cementless total hip arthroplasty: short-term North American experience

Forty-four Madreporic, cementless, total hip arthroplasties performed on 41 patients were reviewed, with special attention to overall clinical results and radiologic findings. Follow-up averaged 17 months (range from 6 to 27 months). Subjectively, 87% of patients rated the results of their operation as being excellent or good; objectively, 92.5% were in the excellent or good category, using the Harris hip scale rating system. Short-term radiologic findings were of major interest, with proximal medial calcar reabsorption (7 hips), thickening of the lateral cortex at the tip of the femoral stem (2 hips) and sclerosis at the tip of the femoral component (15 hips) all being present. Complications were associated with 11 operations, but adversely affected long-term results in only two hips. The authors conclude that short-term clinical results using Madreporic total hip replacement are satisfactory. However, long-term biomechanical effects of stress shielding and use of a large, rigid, femoral component in the uncemented total hip replacement are unknown. A long-term, follow-up study is necessary to demonstrate whether the early radiologic findings in this series are progressive and whether they will result in serious morbidity with time. The authors strongly believe that the Madreporic cementless total hip arthroplasty should be used only in centres dealing with a large volume of hip conditions where staff are committed to documenting and reporting the results of surgery regularly.