Biokinetics of leg assisted human rolling

Abstract

Rolling is a critical activity of daily living. It serves to increase comfort and prevent ischemic-associated injuries to the tissues, i.e., pressure sores. Individuals with Duchenne muscular dystrophy (DMD), an inherited disorder that causes muscle atrophy, lose leg strength and ultimately their ability to roll. The objective of this study was to compare rolling kinematics with and without leg push-off to understand the influence of the legs on rolling. Kinematic data was collected from 12 subjects as the rolled from the supine to side-lying position with and without leg push-off. The kinematic data were used to calculate shoulder and pelvis angles and peak angular velocities. Significance differences were observed in the shoulder peak angular velocities and times required to complete the roll. Pushing with the leg alters the kinematics of rolling, yielding higher peak shoulder angular velocities and longer roll times.