The dual-mobility POLARCUP: first results from a multicenter study.

Dislocation is a leading cause of revision after total hip arthroplasty (THA). To address this risk, dual-mobility technology was developed, which features a mobile polyethylene liner locked onto a femoral head and articulating in a metallic acetabular shell. This study reports clinical outcome data after implantation of the third-generation POLARCUP Dual-Mobility System (Smith & Nephew Orthopaedics AG, Rotkreuz, Switzerland). Primary THA procedures were performed in 150 patients. At 7.1 years, cumulative cup survival according to Kaplan-Meier was 97.4%. The mean Postel-Merle d'Aubigne score improved from 8.9 to 17.1 during the investigation. Two cups were revised at 5.4 and 6.4 years because of aseptic loosening. No dislocations were observed during follow-up. The current results confirm excellent early to midterm clinical outcomes for the POLARCUP Dual-Mobility System.