Dynamic sitting to prevent pressure ulcers in spinal cord injured

At present, clinical interventions and research efforts are not fully successful in defining the risk of pressure ulcer development and as such in eventually preventing pressure ulcers. As a result, the prevalence and incidence values of pressure ulcers remain unacceptably high. It is common sense that healthy subjects do not develop pressure ulcers due to a dynamic variation in sitting posture. This dynamic sitting behavior can be identified and used as a reference values for the optimal sitting behavior of individuals that use a wheelchair and are at risk of developing pressure ulcer. The main research question that has been answered in this thesis is if imposing dynamic sitting behavior by means of the Dynasit chair in Spinal Cord Injured individuals results in elevated tissue viability? In order to define a reference values for the sitting behavior of spinal cord injured individuals, an analysis of healthy sitting behavior has been performed. It was found that healthy subjects change their sitting posture at least every eight minutes. To impose this dynamic sitting behavior on spinal cord injured individuals, the Dynasit chair has been developed. The Dynasit chair is an experimental sitting device developed to investigate the effects of different sitting postures, alternating tuberal support and pelvic orientations on the (sub-) cutaneous tissue viability. Two studies on healthy subjects demonstrated the positive effect of actuation with the Dynasit chair on the tissue load. Regarding the main research question of this thesis, a study performed in 10 male spinal cord injured individuals, confirmed the ability of the Dynasit chair to impose dynamic sitting behavior, based on healthy sitting behavior, in spinal cord injured individuals. This imposed dynamic sitting behavior resulted in significant elevation of the (sub-) cutaneous tissue oxygenation. This elevated tissue oxygenation implies that due to the dynamic sitting, the wheelchair user can sit for prolonged periods of time without tissue breakdown.