Wear in conventional and highly cross-linked polyethylene

Abstract

Ultra-high-molecular-weight polyethylene (UHMWPE) has been used successfully as a bearing surface in total knee arthroplasty for over 30 years, although material failures have typically resulted from gamma irradiationinduced oxidative degradation and the high cyclic stress environment of the knee. Since conversion to non-gamma irradiation sterilization methods, the failure mechanisms that were observed with gamma irradiation in air-sterilized UHMWPE have not occurred. Highly cross-linked UHMWPE has been developed in an effort to further reduce wear in total joint arthroplasty. However, cross-linking reduces the mechanical properties of UHMWPE, including fatigue crack propagation resistance, which may limit its application in total knee arthroplasty. © 2005 Springer Medizin Verlag Heidelberg.