Objective: The purpose of this study is to evaluate the functional performance of patients who underwent to two different types of total knee prosthesis replacement (TKR).

Methods: Kinematics and kinetics of the knee and ankle and electromyography activity of the lower limb muscles were obtained from 16 patients who underwent a TKR. 8 patients had received a fixed bearing prosthesis while the other 8 patients had received a mobile bearing prosthesis. The functional performance of the patients was evaluated using two tests, the gait and the squat. As control, 8 normal subjects, matched by age, were also evaluated.

Results: During the stance phase of gait, patients with TKR showed a reduced knee extensor (internal) moment as compared to normal controls. During the squat test, patients with TKR exhibited a knee ROM that was reduced with respect to normal patients. Moreover, all patients with TKR showed a low velocity of execution of the both tests. There were no significant differences between patients who had received a fixed vs. mobile bearing prosthesis.

Discussion: The results showed that after TKR, the functional performance of the patients is different from that of the normal subjects, regardless of the type of prosthesis implanted.