Abstract
[Purpose] The aim of this study was to determine the knee load of patients with deficiency of anterior cruciate ligament (ACL) by analyses of the effect of movement speed on the knee extension moment during stair descent. [Subjects and Methods] Eight normal subjects and ten patients with ACL deficiency participated in this study. Movements of stair descent at 60, 90, and 120 steps per minute were measured using a three-dimensional motion analysis system composed of infrared cameras and force plates. The knee extension moments, knee flexion angles, and ground reaction forces were compared. [Results] The knee extension moment and flexion angle significantly increased in proportion to increase of movement speed in the early stance phase. However, no significant difference was observed between the knee extension moments of the patients and controls. [Conclusions] The results of this study show that knee load increased with movement speed of stair descent.
