title: Vitamin E-stabilized highly crosslinked polyethylenes: The role and effectiveness in total hip arthroplasty.
abstract: Morphology and design of ultra-high molecular weight polyethylene (UHMWPE or simply PE) acetabular components used in total hip arthroplasty (THA) have been evolving for more than half a century. Since the late-1990s, there were two major technological innovations in PE emerged from necessity to overcome the wear-induced periprosthetic osteolysis, i.e., the development of highly crosslinked PEs (HXLPEs). There are many literature reporting that radiation crosslinked and remelted/annealed (first-generation) HXLPEs markedly reduced the incidence of osteolysis and aseptic loosening. Regardless of such clinical success in the first-generation technologies, there were some recent shifts in Japan toward the use of new second-generation HXLPEs subjected to sequential irradiation/annealing or antioxidant vitamin E (α-tocopherol) incorporation. Although the selection rate of first-generation liners still account for more than half of all the PE THAs (∼58% in 2015), the use of vitamin E-stabilized liners has been steadily growing each year since their clinical introduction in 2010. In these contexts, it is of great importance to evaluate and understand the real clinical benefits of using the new second-generation liners as compared to the first generation. This article first summarizes structural evolution and characteristic features of first-generation HXLPEs, and then provides a detailed description of second-generation antioxidant HXLPEs in regard to the role of vitamin E incorporation on their chemical and mechanical performances in THA.
authors.affiliation: Department of Orthopedic Surgery, Tokyo Medical University, 6-7-1, Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan. Electronic address: kyamamoto@pf6.so-net.ne.jp.
authors.forename: Kengo
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Department of Orthopedic Surgery, Tokyo Medical University, 6-7-1, Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Tateiwa
authors.affiliation: Department of Orthopedic Surgery, Tokyo Medical University, 6-7-1, Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan; Department of Bone and Joint Biomaterial Research, Tokyo Medical University, 6-7-1,Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan. Electronic address: yasuhito@tokyo-med.ac.jp.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Takahashi
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D003432:Cross-Linking Reagents / Q000494:pharmacology* / Q000528:radiation effects; D004058:Diffusion / Q000528:radiation effects; D005544:Forecasting; D006622:Hip Prosthesis; D006801:Humans; D008422:Materials Testing; D010014:Osteolysis / Q000517:prevention & control*; D011095:Polyethylenes / Q000737:chemistry* / Q000528:radiation effects; D011183:Postoperative Complications / Q000517:prevention & control*; D011474:Prosthesis Design; D011839:Radiation, Ionizing; D014810:Vitamin E / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D003432:Cross-Linking Reagents; D011095:Polyethylenes; C111601:ultra-high molecular weight polyethylene; D014810:Vitamin E