Finite element analysis of the contact mechanics of ceramic-on-ceramic hip resurfacing prostheses

Ceramics are good alternative to metal as bearing couple materials because of their better wear resistance. A Finite Element (FE) study was performed to investigate the contact mechanics and stress distribution of Ceramic-on-Ceramic (COC) hip resurfacing prostheses. It was focused in particular on a parametric study to examine the effects of radial clearance, loading, alumina coating on the implants, bone quality, and fixation of cup-bone interface. It was found that a reduction in the radial clearance had the most significant effect on the predicted contact pressure distribution among all of the parameters considered in this study. It was determined that there was a significant influence of non-metallic materials, such as the bone underneath the bearing components, on the predicted contact mechanics. Stress shielding within the bone tissue was found to be a major concern when regarding the use of ceramic as an alternative to metallic resurfacing prostheses. Therefore, using alumina implants with a metal backing was found to be the best design for ceramic resurfacing prostheses in this study. The loading, bone quality, and acetabular cup fixation conditions were found to have only minor effects on the predicted contact pressure distribution along the bearing surfaces.