Clinical Outcomes of Fixed-Bearing Total Knee Arthroplasty Using Non-Cross-Linked Vitamin E-Enriched Polyethylene: A Retrospective Comparison with Conventional Polyethylene at Mean Nine-Year Follow-Up.

Abstract

Ultra-high molecular weight polyethylene (UHMWPE) has long been widely used for inserts in total knee arthroplasty (TKA), and polyethylene wear is a factor affecting implant longevity. Vitamin E-enriched polyethylene (VEPE) was developed to enhance oxidative stability. This study compared the long-term clinical performance of non-cross-linked VEPE with that of conventional UHMWPE (CPE) in TKA. We conducted a retrospective cohort study involving 488 patients (661 knees) who underwent primary TKA between April 1994 and July 2016. Patients were divided into the VEPE (169 knees) and CPE (492 knees) groups. Clinical outcomes, including implant survival, reoperation rates, range of motion (ROM), and patient-reported outcome measures (PROMs), were assessed. At a mean follow-up of 9.0 (range, 0.1 to 20.4) and 9.9 (range, 0.1 to 27.5) years for the VEPE and CPE groups, the Kaplan-Meier survival rates at 10, 15, and 20 years were 97, 93, and 93%, respectively, for the VEPE group and 97, 92, and 85%, respectively, for the CPE group. Reoperation rates were 3.0 and 5.5% in the VEPE and CPE groups, respectively, showing no statistically significant difference (P = 0.22). The one wear-related revision occurred in the CPE group, and none in the VEPE group. There were no significant differences observed between groups in ROM or PROMs. Non-cross-linked VEPE demonstrated clinical outcomes comparable to those of CPE in TKA at a mean follow-up of approximately 10 years.