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A radiographic and histological analysis of 17 retrieved ultrahigh-molecular-weight polyethylene porous-coated femoral stems.

Radiographic and histological and evaluation for failure of 17 retrieved implants was performed. The implants consisted of a titanium stem with a 3-mm ultrahigh-molecular-weight polyethylene coating and an outer 1.5-mm ultrahigh-molecular-weight polyethylene fiber layer. Particular attention was paid to osteolysis, subsidence, debris, and foreign body reaction. Radiographic analysis showed subsidence (14 of 17), osteolytic lesions (9 of 14), and unique posterior medial exostoses (8 of 14). Histological analysis showed no significant evidence of acrylic bone cement either as debris or reactive tissue. There was an intense foreign body reaction directly related to the amount and size of polyethylene debris.