Key Components Related to Pressure Injury Formation: An Initial Investigation Into Pressure Distribution and Blood Perfusion Responses in Wheelchair Users

Soft tissue around bony prominences in the buttocks and back are high risk areas prone to the development of pressure injuries. From a clinical perspective, prevention of pressure injuries all together is the ideal situation. Unfortunately, prevalence rates still reach 47% with recurrence rates even higher. The goals of this study were to evaluate the effects of a series of wheelchair movements, some that currently exist in commercial wheelchairs and some new, on interface pressures and perfusion under the buttocks. 27 chair positions were obtained by varying back recline, seat pan tilt, and articulation of two supports along the back. Although back recline is commonly taught by therapists to be used as a pressure relieving posture, results indicated an increase in pressures under the ischial tuberosities and sacral areas in reclined positions. Articulation of the back supports produced changes in posture moving from an "erect" to "slouched" position. These movements successfully shifted pressures across back regions. Seat pan tilt was effective in shifting pressures off the ischial tuberosity regions. Additionally, in a portion of the participants, seat pan tilt consistently increased perfusion under the ischial tuberosity region. The findings of this research suggest that movements other than back recline should be considered to more effectively alter interface pressures, particularly in high-risk regions like the sacrum and ischial tuberosities.