[Polyethylene wear of the Optifix cementless acetabular component after 5 years]

The aim of this study is to review our experience with the Optifix porous-coated cementless acetabular component at an average 5 year follow-up. In a retrospective clinical investigation, the amount and rate of linear wear of the polyethylene of 26 cementless Optifix acetabular components implanted during a primary Hybrid (Spectron femoral component) total hip replacement in 24 patients, were determined by a comparison of the thicknesses of the cup as measured on the initial and most recent follow-up radiographs. The measurements were corrected for magnification error by direct measurement of the diameter of the femoral head on each radiograph according to the technique of Livermore et al. The mean duration of follow-up was 60 months (range, 48 to 73 months). Linear wear averaged 0.53 +/- 0.12 mm (0 to 2.28 mm) overall, with a mean rate of 0.11 +/- 0.02 mm (range 0 to 0.46 mm) per year p < 0.005. No osteolysis of the acetabulum was seen. None of the acetabular components migrated. Osteolysis of the endosteum of the femur was found in six hips. None of the femoral components subsided. In conclusion, wear of the polyethylene in this cup has not been previously reported, and is consistent with results published with other types of acetabular components.