[Wear of the polyethylene components of endoprostheses following clinical application]

13 various hip joint and knee joint polyethylene components, previously removed from patients after an implantation period of 1.5 to 4 years, were tested and showed an obvious damage of the sliding surface. Macroscopic and microscopic investigations performed by light and scanning electron microscopy revealed an extreme wear of the polyethylene surface respectively an unregular wear at the component's border up to the mm-range. Additional specific X-ray and infrared spectrometric analyses proved in the clear majority of all cases the contribution of bone cement to increased abrasion and its influence upon the intensity of wear. Surplus bone cement which had not been completely removed from the prosthesis component or loosening of prosthesis components are considered as reason for inclusion of bone cement particles between the sliding surfaces.