A kinetic analysis of manual wheelchair propulsion during start-up on select indoor and outdoor surfaces

摘要

The objective of this study was to conduct a kinetic analysis of manual wheelchair propulsion during startup on select indoor and outdoor surfaces. Eleven manual wheelchairs were fitted with a SMARTWheel and their users were asked to push on a course consisting of high and lowpile carpet, indoor tile, interlocking concrete pavers, smooth level concrete, grass, hardwood flooring, and a sidewalk with a 5degree grade. Peak resultant force, wheel torque, mechanical effective force, and maximum resultant force rate of rise were analyzed during startup for each surface and normalized relative to their steadystate values on the smooth level concrete. Additional variables included peak velocity, distance traveled, and number of strokes in the first 5 s of the trial. We compared biomechanical data between surfaces using repeatedmeasures mixed models and paired comparisons with a Bonferroni adjustment. Applied resultant force (p = 0.0154), wheel torque (p < 0.0001), and mechanical effective force (p = 0.0047) were significantly different between surfaces. The kinetic values for grass, interlocking pavers, and ramp ascent were typically higher compared with tile, wood, smooth level concrete, and high and lowpile carpet. Users were found to travel shorter distances up the ramp and across grass (p < 0.0025) and had a higher stroke count on the ramp (p = 0.0124). While peak velocity was not statistically different, average velocity was slower for the ramp and grass, which indicates greater wheelchair/user deceleration between strokes. The differences noted between surfaces highlight the importance of evaluating wheelchair propulsion ability over a range of surfaces.