Mechanical properties and wear performance of cross-linked UHMWPE for orthopaedic joints

Wear of artificial joints is a major problem for the long-term performance of orthopaedic prostheses. Wear particles, especially in the micrometer and nanometric range, seem to be the main factor responsible for osteolysis. In the last years many radiation crosslinking procedures have been developed and applied to UHMWPE for artificial joint components with the aim to increase the wear resistance. In this study a new cross-linking treatment of UHMWPE was introduced and studied. For comparison a standard crosslinked and a non cross-linked UHMWPE were included in the study. All materials were analysed in the non aged condition. Structural, mechanical and wear properties were investigated. Although the mechanical properties of both cross-linked materials were somewhat inferior compared to non-crosslinked UHMWPE, multidirectional wear tests showed a significant improvement of the wear resistance for both crosslinked materials.