Effect of Rear Suspension and Speed on Seat Forces and Head Accelerations Experienced by Manual Wheelchair Riders With Spinal Cord InjuryBy Requejo, Philip S.; Kerdanyan, Grigor; Minkel, Jean; Adkins, Rodney; Waters, Robert; Journal of Rehabilitation Research and Development, Vol. 45, No. 7, pp. 985-996
Publication Date: 2008
Study examined whether the seat reaction forces experienced by wheelchair users were differentially influenced by wheelchair suspension, trunk-muscle innervations, and ground speed. Ten male volunteers with spinal cord injury (SCI) who were manual-wheelchair users participated in the study. Five participants had High SCI, with no trunk control, and the remaining five, with Low SCI, had nearly intact trunk strength with innervated abdominals and thoracic extensors. One rigid-frame wheelchair, the Quickie GPV, and three suspension-frame wheelchairs, the Boing!, A4, and Quickie XTR, were instrumented with load cells and accelerometers to determine the forces transmitted from the seat frame and head accelerations experienced by the riders. A vibration simulator was used to apply small, repeated bumps to wheelchair and rider through the rear wheels. Results showed that seat force and head accelerations were greatest in the rigid-frame wheelchairs and lowest in the spring-type suspension-frame wheelchairs. Participants in the High-SCI category preferred slower speeds than those in the Low-SCI category, and forward head accelerations were greater in High-SCI participants. The authors conclude that wheelchair rear-suspension systems may improve wheelchair mobility function in terms of comfort at higher velocity by minimizing the seat forces and head accelerations experienced by the riders, especially those with higher-level SCI and diminished postural control. Study limitations and implications for further research are discussed.
Assistive Products Discussed: A4
QUICKIE GP AND QUICKIE GPV
VA Rehabilitation Research & Development Service (Web Site: http://www.rehab.research.va.gov )
Link to text: http://www.rehab.research.va.gov/jour/08/45/7/requejo.html