Effects of Two Stroke Patterns on Upper Extremity Kinematics in Wheelchair Propulsion: 1784: Board #221 June 2 3:30 PM - 5:00 PM
METHODS: Twenty physical therapy students (14 females and 6 males, age 27.4 ± 5.9 years, body mass 64.4 ± 9.4 Kg and body height 169.3 ± 9.1 cm) voluntarily participated in this study. Eleven reflective markers were placed on thorax (3 markers) and right scapula (3 markers), humerus (3 markers), third metacarpophalangeal joint and wheelchair axle. Participants propelled a standard wheelchair on a stationary roller system at the speed of 0.9 m/s and 1.8 m/s using semicircular (SC) and single loop (SL) stroke patterns, for 20 seconds. Three-dimensional propulsive movements were recorded at 100 Hz. The kinematic differences between two patterns and two speeds were examined using 2-way repeated measures ANOVA (a <.05).
RESULTS: Results showed a significant longer drive phase and shorter recovery phase in SC when compared to SL, and no difference found on cycle time. When the initial contact angles are similar in both stroke patterns, the SC had a significant longer angular pushing range at both speeds. The SC had a significant smaller scapular protraction range of motion (ROM) and greater maximal shoulder abduction angle and ROM than the SL did in the drive phase. In the recovery phase, the SC had significant less ROM of scapular tilting, protraction, and shoulder abduction and internal rotation with comparison to the SL. The SC had significant lower hand linear velocity and acceleration in the recovery phase than the SL did.
CONCLUSION: To maintain the same propulsive speed, the longer drive phase, smaller scapular protraction, and lower hand linear velocity and acceleration (in the recovery phase) may make SC the better stroke technique in wheelchair propulsion when compared to the SL.