Seat-interface pressure: A pilot study of the relationship to gender, body mass index, and seating position

Abstract

Stinson MD, Porter-Armstrong A, Eakin P. Seat-interface pressure: a pilot study of the relationship to gender, body mass index, and seating position. Arch Phys Med Rehabil 2003;84:405-9. Objectives: To investigate the relationship between interface pressure and gender, body mass index (BMI), and seating positions, and to evaluate the implications for clinical practice. Design: Group design. Setting: Pressure mapping laboratory. Participants: Sixty-three student volunteers (44 women, 19 men; mean age, 22.2[plusmn]5.1y). Interventions: Seated-interface pressure was measured using the Force Sensing Array pressure mapping system. Seating positions used included recline (10[deg ], 20[deg ], 30[deg ]), foot support, and foot elevation. Main Outcome Measures: Interface pressure in the form of both average pressure (mean of the pressure sensor values) and maximum pressure (highest individual sensor value). Results: Both average and maximum pressures were independent of gender, while average pressure had a significant positive correlation with BMI ( r=.381, [alpha ]=.01 level). Recline of the chair by 30[deg ] significantly reduced average pressure ( P[lt ].001), whereas recline by 10[deg ] or 20[deg ] had no significant effect. Recline by 10[deg ], 20[deg ], and 30[deg ] did not significantly alter maximum pressure. Elevation of the feet on a footstool reduced average pressure to a level approaching statistical significance, while supporting participants' feet versus leaving them unsupported significantly increased average pressure at a 0[deg ], 10[deg ], 20[deg ], and 30[deg ] recline ( P[lt ].01) and maximum pressure at 0[deg ], 10[deg ] ( P[lt ].01), and 30[deg ] ( P[lt ].05). Conclusions: Elevating clients' feet and reclining their chair by 30[deg ] reduced interface pressure and the associated risk of pressure ulcer development. Additional research is required, however, to replicate this study with participants at increased risk of pressure ulcer development. [copy ] 2003 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation