Comparison Of Long-term Conventional Uhmwpe Retrievals With Mid-term Moderately Cross-linked Uhmwpe Retrievals
نویسندگان
چکیده
Introduction: Ultra-high molecular weight polyethylene (UHMWPE) is the most widely used bearing surface option in total hip arthroplasty. Radiation cross-linking has improved the wear resistance of conventional UHMWPE. Radiation cross-linking also generates residual free radicals, adversely affecting long-term oxidative stability. Post irradiation melting is effectively used to eliminate residual free radicals and improve stability. However, recent retrieval studies have reported oxidation in some irradiated and melted UHMWPE bearings after long in vivo durations [1], and significant oxidative degradation after shelfstorage ex vivo [2]. Conventional polyethylene bearings are typically gamma sterilized; hence they contain residual free radicals. These show high levels of oxidation in the long-term. Historically some conventional polyethylenes were sterilized using gas plasma (GP) or ethylene oxide (EtO); hence they contain no detectable free radicals. The GP and EtO polyethylenes would serve as proper controls and studying the long-term oxidative stability of irradiated and melted UHMWPE components. Our objective was to investigate GPand EtO-sterilized conventional liners with up to 25 years of in vivo service to 50kGy gamma-radiation cross-linked/melted, gas-plasma sterilized liners [4].
منابع مشابه
Tibial Insert Retrievals Allow Comparison of Wear and Oxidation in Conventional and Highly Cross-linked UHMWPE
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