Influence of body mass and lower limb length on knee flexion angle during walking in humans

Abstract

Despite abundant knowledge about the relationship between body size (i.e., body mass, lower limb length) and limb posture during locomotion on the level of interspecies variability, little is known about variation on the intraspecific level. We used an experimental approach to evaluate the relationship between body size and knee posture during walking in humans at specific gait events and at each percentage point of normalized stance phase. We detected significant negative correlation between knee flexion angle and body mass at the second peak of the vertical ground reaction force, but, in contrast to a previous study, we found no significant relationship between knee flexion angle and lower limb length. Although not significant, strengthened correlations between knee flexion angle and lower limb length were detected at late stance phase and these coincide well with the strengthened correlations between knee flexion angle and body mass. Our findings support the view that body size influences limb posture during locomotion even on the intraspecific level. In humans, larger individuals tend to use more extended knee postures in late stance of walking than do smaller individuals.