Abstract:Objective To study the contact performance of hip joint replacements with different material combinations typically used in clinic. Methods The finite element model of spherical conformal contact of hip joint replacements was developed to analyze the different contact mechanics performance of hip joint replacements with different material combinations by simulation test under a vertical constant load within one normal walking gait. The corresponding wear prediction was also evaluated. Results The contact mechanics performances of hip joint replacements with the material combination of metal-on-metal (MOM), metal-on-ceramic (MOC), ceramic-on-ceramic (COC), metal-on-polyethylene (MOP) and ceramic-on-polythene (COP) were analyzed. The results obtained from the simulations showed that contact stress was decreased in the order of COC>MOC>MOM>COP>MOP, while contact area was decreased in the order of MOP>COP>MOM>MOC>COC. Conclusions Hip joint replacement with the material combination of high elastic modulus and low Poisson’s ratio has smaller deformation, but could induce larger local stress, while flexible material polythene of low elastic modulus and high Poisson’s ratio might have smaller concentrated contact stress, but cause larger deformation and edge contact phenomenon on the acetabulum cup of hip joint replacements. In addition, hip joint replacements with MOC and MOM material combination may have lower contact bearing performance, which provides references for material choices of typical artificial hip joints in clinic.