Knee osteoarthritis (OA) is a common joint disease highly prevalent among aged elderly and increasing from middle age. Patients with medial knee OA are reportedly 10 times more common than patients with lateral knee OA. Women are more predisposed to knee OA than males, and race is also related to the prevalence rate of knee OA. The female/male ratio in Japan is higher than the ratio among Caucasians in the United States. The prevalence rate of knee OA among Japanese women has been reported to be 11.4% in their 40s, and the rates in the 50s, 60s and 70s are 30.3%, 57.1%, and 71.9%, respectively. The external knee adduction moment (KAM) is the moment at which the tibia rotates in the adduction (varus) direction associated with the femur with the axis of the knee joint center on the frontal plane. Knee adduction moment (KAM) during gait as a surrogate measurement of the medial compression force (MCF) has been associated with medial knee OA reported linear regression equations with KAM and knee flexion moment (KFM) to obtain MCF using one patient with a force-measuring knee implant. The KAM and MCF impulse with area under KAM- or MCF-time curve reflecting both the magnitude and duration of knee load during gait are also important information for medial knee pathology. For more information about this article, kindly go through the above link.