%0 Journal Article
%T Low wear rate at 6
%A Einar Lindalen
%A Lars Nordsletten
%A Peder S Thoen
%A Stephan M R£¿hrl
%A £¿ystein H£¿vik
%J HIP International
%@ 1724-6067
%D 2019
%R 10.1177/1120700018798790
%X Free radicals formed in the cross-linking process may over time alter the mechanical properties of highly cross-linked polyethylene. Vitamin E-infused highly cross-linked polyethylene was therefore developed to achieve low wear-rate and good mechanical properties in the long term. To present 6-year results from the initial randomised controlled trial. We measured wear and periacetabular bone remodelling in cementless total hip arthroplasty; 32- or 36-mm Biolox Delta heads and vitamin E-infused highly cross-linked polyethylene (E-Poly) were used. Markerless radiosterometric analysis measured the in vivo wear and dual energy x-ray absorptiometry was used to analyse bone remodelling in 40 hips at 6-year follow-up. In the proximal direction the wear for 32- and 36-mm heads was 0.15£¿mm (95% confidence interval [CI], 0.08¨C0.21) and 0.06£¿mm (95% CI, -0.002¨C0.12), respectively (p = 0. 015). However, between 3£¿months and 6£¿years (excluding the period of ¡°bedding in¡±), the proximal wear for 32- and 36-mm heads was 0.10£¿mm (95% CI, 0.05¨C0.15) and 0.05£¿mm (95% CI, -0.01¨C0.11), respectively (p = 0.12). The annual proximal wear rate for 32- and 36-mm heads from 3£¿months to 6£¿years was 0.02£¿mm and 0.01£¿mm, respectively. There was no difference in bone remodelling around the cup from baseline to 6£¿years for the total material and no differences between study groups. Wear of this vitamin E-infused highly cross-linked polyethylene is still low at 6-year follow-up, with no significant difference in wear from 3£¿months to 6£¿years between 32- and 36-mm heads
%K Cross-linked
%K hip
%K radiosterometric
%K RSA
%K THA
%K vitamin E
%U https://journals.sagepub.com/doi/full/10.1177/1120700018798790