212 Patients scheduled to undergo TKA, with unilateral symptomatic knee osteoarthritis, were included in this trial to determine the efficacy of a novel prosthesis hypothesized to improve lower limb power output. Recent research has suggested that knee flexion/extension may occur around a fixed axis in the femur, which led to the development of a single-radius implant. Patients were randomized to implant groups with different joint radius designs: A single-radius group or a multi-radius group. The results of this study showed that patients who received the single radius implants experienced significantly greater extensor power (52 weeks after follow-up) than current traditional (multi-radius) techniques. However, this improved power did not translate to improved physical function.