In vivo wear of bilateral total hip replacements: conventional versus crosslinked polyethylene

Crosslinked polyethylene (PE) was developed to reduce volumetric wear in prosthetic joints. Hip simulator studies have shown promising results but there is as yet limited clinical data. We identified three patients with bilateral total hip replacements who received a crosslinked PE liner (Marathon^TM, DePuy, Warsaw, IN, USA) on one side and a conventional PE insert (Enduron^TM, DePuy) on the contralateral side. As an assessment of in vivo PE wear, linear head penetration was measured on standardized radiographs using a validated computer-assisted technique. In all the three cases, a marked reduction of more than 70% in volumetric wear was found in association with Marathon crosslinked PE. These case reports support the efficacy of this type of crosslinked PE in a selected group that allows direct comparison of the two different materials without the influence of patient-related factors such as activity, gender, weight, or others.