Abstract
Background and purpose - The use of crosslinked polyethylene in total hip arthroplasty (THA) has decreased wear remarkably. It has been suggested that the antioxidative effects of vitamin E may enhance the wear properties of polyethylene even further. This study evaluates revision rates between vitamin E-infused polyethylene liners (E1 and E-poly, ZimmerBiomet, Warsaw, IN, USA) versus moderately crosslinked polyethylene (ModXLPE) liners from the same manufacturer used in primary THA.Patients and methods - We conducted a study based on data from the Finnish Arthroplasty Register. The study group consisted of 2,723 THAs with a vitamin E-infused liner and a reference group of 2,707 THAs with a moderately crosslinked polyethylene liner. Survivorship, revision risk, and re-revision causes were compared between groups.Results - The 7-year survival of the vitamin E-infused polyethylene liner group and of the reference group with revision for any reason as the endpoint was comparable (94% [95% CI 92.9-94.9] and 93% [CI 91.9-93.9], respectively). The adjusted hazard ratio (HR) for any revision was similar between the groups (0.7 [CI 0.4-1.1]). When revision for aseptic loosening was studied as the endpoint, the survival for the study group was 99% (CI 98.6-99.4) and for the reference group 99% (CI 98.7-99.5), and the risk of revision was comparable between the study groups (HR 1.3 [CI 0.7-2.5]).Interpretation - After an observation period of 7 years vitamin E-infused liners shows results equal to results obtained with crosslinked polyethylene liners.