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Vitamin E-stabilized UHMWPE for Total Joint Implants: A Review

  • Symposium: UHMWPE for Arthroplasty: From Powder to Debris
  • Published:
Clinical Orthopaedics and Related Research®

Abstract

Background

Osteolysis due to wear of UHMWPE limits the longevity of joint arthroplasty. Oxidative degradation of UHMWPE gamma-sterilized in air increases its wear while decreasing mechanical strength. Vitamin E stabilization of UHMWPE was proposed to improve oxidation resistance while maintaining wear resistance and fatigue strength.

Questions/purposes

We reviewed the preclinical research on the development and testing of vitamin E-stabilized UHMWPE with the following questions in mind: (1) What is the rationale behind protecting irradiated UHMWPE against oxidation by vitamin E? (2) What are the effects of vitamin E on the microstructure, tribologic, and mechanical properties of irradiated UHMWPE? (3) Is vitamin E expected to affect the periprosthetic tissue negatively?

Methods

We performed searches in PubMed, Scopus, and Science Citation Index to review the development of vitamin E-stabilized UHMWPEs and their feasibility as clinical implants.

Results

The rationale for using vitamin E in UHMWPE was twofold: improving oxidation resistance of irradiated UHMWPEs and fatigue strength of irradiated UHMWPEs with an alternative to postirradiation melting. Vitamin E-stabilized UHMWPE showed oxidation resistance superior to that of irradiated UHMWPEs with detectable residual free radicals. It showed equivalent wear and improved mechanical strength compared to irradiated and melted UHMWPE. The biocompatibility was confirmed by simulating elution, if any, of the antioxidant from implants.

Conclusions

Vitamin E-stabilized UHMWPE offers a joint arthroplasty technology with good mechanical, wear, and oxidation properties.

Clinical Relevance

Vitamin E-stabilized, irradiated UHMWPEs were recently introduced clinically. The rationale behind using vitamin E and in vitro tests comparing its performance to older materials are of great interest for improving longevity of joint arthroplasties.

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Acknowledgments

This review originates from the work on vitamin E-stabilized UHMWPEs performed by the authors in collaboration with numerous researchers. The authors thank their collaborators and especially their mentors, Drs. Luigi Costa and Orhun Muratoglu, respectively.

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Correspondence to Pierangiola Bracco MD.

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One or more of the authors or of the authors’ institutions have received funding from NIH Grant AR051142 (EO); Biomet, Inc, Warsaw, IN (EO); Bioster SpA, Seriate, Italy (PB); Lima Lto, San Daniele del Friuli, Italy (PB); Zimmer, Inc, Warsaw, IN (EO, PB); and Harris Orthopaedic Laboratory funds (EO).

This work was performed at Università di Torino and Massachusetts General Hospital.

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Bracco, P., Oral, E. Vitamin E-stabilized UHMWPE for Total Joint Implants: A Review. Clin Orthop Relat Res 469, 2286–2293 (2011). https://doi.org/10.1007/s11999-010-1717-6

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