Kinematics of wheelchair propulsion in adults and children with spinal cord injury

Abstract

This study examined the kinematic features of wheelchair propulsion in two neurologically matched groups of adults and children with uncomplicated spinal cord injury. The average mass and age of the pediatric group was much smaller than the adult group (37.4kg and 11.3 years vs 68.5kg and 33.5 years). Each subject propelled his/her own chairs and new, low-mass wheelchairs at a steady, nominal speed of 2 m/sec across a level surface. Three dimensional video analysis determined the movement of upper body angles (elbow, shoulder, trunk, and shoulder abduction) based on reflective markers placed on the subjects' shoulder, elbow, wrist, and hip joints. Analysis of the temporal factors showed that although the average group overground velocities of the adult group (2.4m/sec) were significantly greater than the pediatric group (2.3m/sec), the two groups spent comparable proportions of the wheeling cycle in propulsion (24%). Analysis of the angular kinematics (elbow, shoulder, and shoulder abduction angular changes over a time normalized wheeling cycle) showed that whereas the pediatric group did show significant absolute angular differences from the adult group, the angular changes over time were the same in both groups. The implications of this work are that, for the first time, it can be said that children propel their wheelchairs in the same manner as adults. In addition, these data were similar to those previously reported in athletic adult populations. We conclude that published data from adult wheelchair users may be applied to pediatric wheelchair users, thus providing a basis for pediatric wheelchair prescription. Further studies using kinetic measurements over longer time periods may be necessary to elucidate other potential similarities between the adult and pediatric wheeling style.