KINEMATIC CHARACTERIZATION OF WHEELCHAIR PROPULSION

Rehabilitation scientists and biomedical engineers have been investiga ting wheelchair propulsion biomechanics in order to prevent musculoske letal injuries. Several studies have investigated wheelchair propulsio n biomechanics; however, few have examined wheelchair propulsion strok e patterns. The purpose of this study was to characterize wheelchair p ropulsion stroke patterns by investigating joint accelerations, joint range of motions, wheelchair propulsion phases, and stroke efficiency. Seven experienced wheelchair users (5 males, 2 females) were filmed u sing a three-camera motion analysis system. Each subject pushed a stan dard wheelchair fitted with a force-sensing pushrim (SMART(Wheel)) at two speeds (1.3 and 2.2 m/s). The elbow angle was analyzed in the sagi ttal plane, while the shoulder joint was analyzed in the sagittal and frontal planes. Three distinctly different stroke patterns: semi-circu lar (SC), single looping-over-propulsion (SLOP), and double looping-ov er-propulsion (DLOP), were identified from the kinematic analysis. Thr ough our analysis of these patterns, we hypothesized that SC was more biomechanically efficient than the other stroke patterns. Future studi es using a larger number of subjects and strokes may reveal more signi ficant distinctions in efficiency measures between stroke patterns.