RehabMove 2018: PROPULSION BIOMECHANICS DURING WHEELCHAIR TURNING MANOEUVERS IN YOUNG ABLE-BODIED MEN AND WOMEN

The purpose of this study was to characterize push characteristics and force requirements of left (TL) and right (TR) turnings compared with straight-line (SL) propulsion between men and women. Twenty able-bodied subjects (10 men; 10 women, age: 26 ± 5 years, height: 1.68 ± 0.07 m, body mass: 64.2 ± 8.4 kg) received a 12-min familiarization trial of multiple turns around a rectangular course. Subsequently, they performed three tasks in a random order: SL, TR and TL. A Smartwheel was mounted at the right wheel of a standard wheelchair to measure forces and timing parameters of the inner hand during TR or the outer hand during TL. A repeated measure analysis of variance was used to detect the difference across tasks and groups (P < 0.05). In the turning manoeuvres, adjustments were made in the approach, turning and depart phase. Speed of TR and TL was lower compared with SL (P < 0.05). TR was accomplished by retarding speed, initiated in the approach phase, accompanied by increasing braking force of the inner hand (11.2 times higher compared with SL) and changing push characteristics (higher frequency) of the outer hand during the turning phase. In TL, peak force and most timing parameters were similar to SL, except the approach phase (lower peak force for TL). Differences in speed and peak force requirements were found between genders (P < 0.05). It can be concluded that that turning manoeuvres require unique execution of force requirements and push characteristics, which needs further study and need to be taken into consideration in the effort to preserve upper limb function. Sex differences in force and push characteristics exist during turning. This is the first study addressing turning biomechanics in wheelchair propulsion.