Numerical study of tibial inserts made of conventional and vitamin E blended UHMWPE with and without cross linking in total knee replacement under EHL conditions.

Total Knee Replacement (TKR) effectively improves mobility and reduces pain in patients with severe arthritis. Polyethylene wear limits implant longevity by inducing osteolysis and aseptic loosening. Therefore, this study evaluates the lubrication performance of four clinically relevant UHMWPE formulations representing distinct combination of crosslinking dosage and antioxidant. An ellipsoidal on-plane model of an artificial knee joint is considered and all governing equations are solved using Newton Raphson method. The results indicate that, vitamin E blended UHMWPE without cross linking exhibits highest contact pressure with only a marginal reduction in film thickness, while achieving the lowest coefficient of friction under EHL conditions.