Knee biomechanical evaluation Estimating the therapeutic efficacy of knee TKA is subjective in current clinical practice because methods of functional biomechanics assessment are complex and difficult to apply. It was suggested that gait measurements should be monitored after surgery for patients with knee osteoarthritis (OA) to evaluate treatment outcome and recovery. KneeKGTM (Emovi Inc., Laval, Quebec, Canada), a simple and minimally-invasive method of measuring 3D knee kinematics, has been developed and is now available commercially. In this system, motion sensors are quasi-rigidly attached to the leg with a non-invasive ancillary system, which reduces errors in skin movement in relation to bone. This measurement tool has been validated by satisfactory assessment of its accuracy and the reproducibility of femoro-tibial 3D kinematics during gait.