Mid-term results of total knee replacement with single-radius versus multi-radius posterior-stabilized implants.

Objective: Single-radius femoral total knee endoprosthesis designs were introduced with the promise of better clinical and functional results by means of superior biomechanical characteristics. The aim of this study was to compare the mid-term clinical, functional, radiologic, and survivorship outcomes of 2 types of posterior-stabilized knee replacement systems: the single-radius Scorpio® (Stryker®, Mahwah, NJ, USA) and the multi-radius NexGen® (Zimmer®, Warsaw, IN, USA).

Methods: This retrospective observational study included 139 patients (164 knees) that underwent total knee replacement (TKR) between October 2004 and December 2010: 94 knees (75 patients) with Scorpio® and 70 knees (64 patients) with NexGen®.