A three dimensional multi-segmental analysis of the energetics of normal and pathological human gait

Segmental mechanical energy changes were studied in normal adults as a function of walking speed and in a group of subjects with pathologically impaired gait walking at their normal speed to determine the usefulness of this parameter in evaluating locomotor dysfunction. Of particular significance, the degree of exchange between potential and kinetic energy within and between limb segments was quantitatively evaluated. Due to the nature of most pathological gaits, no assumptions were made to impose symmetry between the right and left extremities and the translational as well as rotational kinetic energy of each of the limb segments was computed in three dimensions. Additionally, the torso was modeled as a group of segments with distributed mass in contrast to the commonly employed concentrated point mass model. In toto, a three dimensional twelve segment energetic analysis of the human body was developed and employed. In normal subjects, this analysis suggests a greater exchange between potential and kinetic energy near individually preferred walking speeds. Patterns of energy change noted in those subjects with locomotor dysfunction varied with the type of pathological disorder.