Usage of tilt-in-space, recline, and elevation seating functions in natural environment of wheelchair users.

This study examined the usage of powered seating functions, including tilt-in-space, backrest recline, and seat elevation, among a group of wheelchair users during their typical daily activities. Twelve individuals who used a power wheelchair with seating functions participated in the study. They drove their own wheelchair and used the seating functions as needed in their community environment for about 2 weeks while the seating function usage was recorded with a portable device. We found that subjects occupied their wheelchair for 11.8 +/- 3.4 hours a day (all data shown as mean +/- standard deviation). While occupying their wheelchairs, they accessed tilt-in-space, backrest recline, and seat elevation 19 +/- 14 times a day for 64.1% +/- 36.8%, 12 +/- 8 times for 76.0% +/- 29.8%, and 4 +/- 4 times for 22.5% +/- 34.9%, respectively. Subjects chose to stay in tilted and reclined positions in their wheelchair for 39.3% +/- 36.5% of their time each day. They spent little time in a fully upright position. Subjects changed their seating positions every 53.6 +/- 47.0 minutes. Time spent in positions of different seating pressures varied among subjects. The information collected could enhance clinical practice of wheelchair provision, resulting in better compliance with clinical instructions and appropriate use of seating functions among wheelchair users.