High wear-resistance of new ceramics in hip simulator study

摘要

Concerns over PE-mediated osteolysis are the driving interest in today's alternative bearing combinations for total hip replacements (THR). Given that the major limitation of the polyethylene (PE) bearing may be its poor wear-resistance, one may wonder why CoCr or ceramic cups have not yet replaced PE cups? For example, wear of metal or ceramic cups is typically measured in micrometer, i.e. <1 to 5 mu m/year, whereas wear of PE cups is measured in millimeters, i.e. 0.07 to 0.6 mm per year. The objective of this study was to clarify the relative wear benefits of ceramic-ceramic (C-C) as demonstrated by hip-simulator studies. In this report, the wear of an experimental composite ceramic (Crystaloy~(TM)) was compared to that of an alumina-alumina system which has a clinical history of nearly 3 decades. These data are compared to wear-rates from two clinical studies of C-PE THR systems from Japan.