The effects of a dynamic tuberal support on ischial buttock load and pattern of blood supply.

Sitting acquired pressure ulcers are places of tissue breakdown that mainly occur under the ischial tuberosities (ITs). Successive durations of pressure relief help the buttock tissue recover from sustained deformation and blood-flow stagnation. A computer-aided simulator chair was developed with two adjustable tuberal support elements (TSE) integrated in a force-sensing seating plane (FSP).

Analysis of healthy sitting behavior: interface pressure distribution and subcutaneous tissue oxygenation.

Pressure ulcers are a large problem in individuals who use a wheelchair for their mobility and have limited trunk stability and motor function. Because no relation between interface pressure and pressure ulcer development has been established and no clinical threshold for pressure ulcer development can be given, looking at the sitting behavior of nondisabled individuals is important. Nondisabled individuals do not develop pressure ulcers because they continuously shift posture.

Effects of dynamic sitting interventions on tissue oxygenation in individuals with spinal cord disorders.

Study Design: An explorative cross-sectional study.

Objectives: The objective of this study was to investigate the possibility of imposing dynamic sitting behavior on individuals with spinal cord disorders by using the Dynasit chair and to investigate its effect on the (sub-)cutaneous tissue oxygenation.

Setting: Rehabilitation Centre het Roessingh, Enschede, the Netherlands.

Decoupled pelvis rotation in sitting: a passive motion technique that regulates buttock load associated with pressure ulcer development.

Wheelchair-users who cannot reposition themselves often suffer from pressure ulcers which are places of tissue breakdown in the buttock region under the sacrum and ischial tuberosities. Periodic pressure relief is needed to recover the buttock tissue from continuous deformation and impairment of tissue perfusion. Because pelvis alignment directly affects body posture and buttock load, a passive motion technique was developed that adjusts pelvis orientation independent from the trunk and seat support.

Can pelvis angle be monitored from seat support forces in healthy subjects?

Individuals who cannot functionally reposition themselves often need dynamic seating interventions that change body posture from automatic chair adjustments. Pelvis alignment directly affects sitting posture, and systems that adjust and monitor pelvis angle simultaneously might be applicable to control body posture in sitting. The present study explores whether it is feasible to monitor pelvis angle from seat support forces.