The effect of a newly developed wheelchair with thoracic and pelvic support on cervical movement and muscle activity in healthy elderly women

Abstract

BackgroundAs the population ages, the number of elderly individuals using a wheelchair is increasing. A standard wheelchair with a vertical backrest (S-WC) pushes on a kyphotic spine and exacerbates forward head posture. Forward head posture limits cervical movement. We used a new wheelchair (N-WC) that does not exacerbate thoracic kyphosis. The N-WC does not have a flat backrest, but has a support belt for the thorax and pelvis. The purpose of this study was to compare head-neck angle, cervical range of motion, and cervical muscle activity in the N-WC and the S-WC in healthy elderly women. MethodsWe measured head-neck alignment, trunk tilt angle, cervical muscle activity, and pressure distribution on the backrest. Data from 17 subjects were analyzed. ResultsHead-neck angle was close to neutral in the N-WC. The trunk was tilted further back and the area over which pressure was distributed on the backrest was expanded in the N-WC. Cervical range of motion and cervical muscle activity during neck extension were significantly greater in the N-WC than in the S-WC, but during neck flexion, there was no significant difference between the wheelchairs. ConclusionIn the N-WC, head-neck alignment was close to the neutral posture because the wheelchair support belt accommodated kyphosis and did not push the spine forward, so cervical muscle activity may be reduced when at rest. These results suggest that the N-WC prevented forward head posture and improved cervical movement and muscle activity.