title: Investigation of peak pressure index parameters for people with spinal cord injury using wheelchair tilt-in-space and recline: methodology and preliminary report.
abstract: The purpose of this study was to determine the effect of the sensel window's location and size when calculating the peak pressure index (PPI) of pressure mapping with varying degrees of wheelchair tilt-in-space (tilt) and recline in people with spinal cord injury (SCI). Thirteen power wheelchair users were recruited into this study. Six combinations of wheelchair tilt (15°, 25°, and 35°) and recline (10° and 30°) were used by the participants in random order. Displacements of peak pressure and center of pressure were extracted from the left side of the mapping system. Normalized PPI was computed for three sensel window dimensions (3 sensels × 3 sensels, 5 × 5, and 7 × 7). At least 3.33 cm of Euclidean displacement of peak pressures was observed in the tilt and recline. For every tilt angle, peak pressure displacement was not significantly different between 10° and 30° recline, while center of pressure displacement was significantly different (P < .05). For each recline angle, peak pressure displacement was not significantly different between pairs of 15°, 25°, and 35° tilt, while center of pressure displacement was significantly different between 15° versus 35° and 25° versus 35°. Our study showed that peak pressure displacement occurs in response to wheelchair tilt and recline, suggesting that the selected sensel window locations used to calculate PPI should be adjusted during changes in wheelchair configuration.
authors: Rehabilitation Engineering Laboratory, Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, 1206 South Fourth Street, MC-588, Champaign, IL 61820, USA ; Department of Creative Product Design, Asia University, Taichung 41354, Taiwan.
authors: Chi-Wen
authors: CW
authors: Lung
authors: Rehabilitation Engineering Laboratory, Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, 1206 South Fourth Street, MC-588, Champaign, IL 61820, USA.
authors: Tim D
authors: TD
authors: Yang
authors: Department of Rehabilitation Sciences, University of Hartford, West Hartford, CT 06117, USA.
authors: Barbara A
authors: BA
authors: Crane
authors: Division of Disability Resources and Educational Services, University of Illinois at Urbana-Champaign, Champaign, IL 61820, USA.
authors: Jeannette
authors: J
authors: Elliott
authors: Department of Physical Medicine and Rehabilitation, University of Pittsburgh Medical Center, Pittsburgh, PA 15206, USA.
authors: Brad E
authors: BE
authors: Dicianno
authors: Rehabilitation Engineering Laboratory, Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, 1206 South Fourth Street, MC-588, Champaign, IL 61820, USA.
authors: Yih-Kuen
authors: YK
authors: Jan
mesh_terms: D000328:Adult; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011187:Posture / Q000502:physiology; D011312:Pressure; D013119:Spinal Cord Injuries / Q000503:physiopathology* / Q000534:rehabilitation*; D016474:Weight-Bearing / Q000502:physiology; D014910:Wheelchairs