The antioxidant and non-antioxidant contributions of vitamin E in vitamin E blended ultra-high molecular weight polyethylene for total knee replacement.

Vitamin E (VE) blended ultra-high molecular weight polyethylene (UHMWPE) has been developed in Japan as a material for use in total knee replacement (TKR). Various results have demonstrated that VE blended UHMWPE reduces the incidence of delamination failure and lowers the amount of wear produced during knee simulator testing. It was also found that wear particles from VE blended UHMWPE elicited a reduced biological response compared to conventional UHMWPE.

Strain-induced crystallization and orientation of vitamin E-blended ultrahigh molecular weight polyethylene.

The effects of vitamin E addition on the strain-induced crystallization and molecular chain orientation of ultrahigh molecular weight polyethylene (UHMWPE) were examined in order to clarify the wear mechanism of vitamin E-blended UHMWPE in knee prostheses. The structure changes of vitamin E-blended UHMWPE before and after tensile strain were analyzed by X-ray diffraction, Raman spectroscopy and image correlation method. The vitamin E-blended UHMWPE exhibited lower strain-induced crystallization than virgin UHMWPE but a higher Ic value in Raman spectroscopic analysis.