Le polyéthylène hautement réticulé de deuxième génération dopé à la vitamine E versus conventionnel dans l’arthroplastie totale de hanche. Étude prospective randomisée à 4ans minimum de recul

摘要

The purpose of this prospective randomized study was to compare the minimum 3-­year follow-­ up penetration of cementless polyethylene sockets of the same design in two configurations in a consecutive series of total hip arthroplasty.Between May 2010 and May 2011, 100 patients (100 hips) with a mean age of 70.8 ± 7.5 years were randomized (power of 80%, alpha of 5%) to receive either vitamin E doped highly cross-­ linked (group Vitamys, 0.1% vitamin E blended, 10 Mrads of gamma radiation, 50 hips) or moderately cross‐linked (group RM, 3 Mrads of gamma radiation in nitrogen, 50 hips) material. The cementless polyethylene cups were coated with pure titanium particles. All other parameters, including the 28 mm diameter metal femoral head, stem, surgical approach and postoperative course were identical in both groups. The primary criterion for evaluation was linear head penetration measurement, using the Martell system, performed by an investigator blinded to the polyethylene type. Both creep and steady state wear were measured.At the time of the minimum 3-­year follow-­up evaluation, 34 hips in the Vitamys group and 32 hips in the RM group have had complete data available for analysis (median follow‐up of 3.02 and 3.13 years, respectively). The median creep measured 0.02 mm versus 0.3 in the Vitamys and RM groups, respectively (Mann-­Whitney, p=0.04). The median steady state penetration rate from one year onwards was ‐0.097 mm/year in the Vitamys group versus 0.064 mm/year in the RM group (Mann and Whitney test, p=0.04). No complication specific to the material was recorded, and no patient was revised because of wear and/or osteolysis.This study provides the first randomized in vivo wear measurements of Vitamin E doped highly cross-­linked acetabular components. These early 3-­year follow-­up results demonstrated encouraging wear performance of vitamin E blended highly cross-­linked polyethylene. Longer term follow-­up is necessary to monitor the performance of these devices.