Comparisons of Joint Kinetics in the Lower Extremity Between Stair Ascent and Descent

Abstract Stair locomotion has been used in the rehabilitation of the lower extremity as a motor performance test and multi-joint exercise. Controversies exist regarding joint loads during stair locomotion. The purposes of the study were to investigate the three-dimensional kinetics of the lower limb joints during stair locomotion, and to compare them with those during level walking. Ten normal young adults walked, and ascended and descended stairs in a gait laboratory while kinematic and kinetic data were collected and analyzed. The results showed that the intersegmental resultant forces at the joints during the activities were generally similar in pattern but the force magnitudes, moments and angular impulses were significantly different. The general impression that the loads in the lower limb were larger during stair descent than stair ascent only holds for certain kinetic variables. Most of the peak joint moments and angular impulses over the entire stance phase were bigger during stair ascent than descent. The study provides a complete knowledge of the three-dimensional loading patterns at and dynamic functions of the lower limb joints during level walking and stair locomotion. It will be helpful for the planning and evaluation of treatment programs for patients with neuromusculoskeletal pathologies in the lower extremities.