Electrical muscle stimulation for pressure variation at the seating interface.

A new method is proposed for pressure sore prevention using electrical muscle stimulation (EMS). Potential mechanisms through which EMS may act for this purpose are discussed, including both short-term/dynamic and chronic effects. Measurements of maximum pressure variation in three able-bodied subjects using low levels of stimulation were performed. Pressure distribution changes were also measured. Fatigue effects on pressure redistribution were studied for four able-bodied subjects as well as for one C4, complete spinal cord injured individual. The results indicate that EMS produces sizeable pressure reduction under the ischial tuberosity, with redistribution occurring over other parts of the seating surface in able-bodied subjects. Fatigue effects were not observed in the four able-bodied subjects even after prolonged stimulation. Fatigue was observed with the spinal cord injured subject, but only after extensive stimulation. These studies demonstrate the feasibility of using EMS at relatively low intensity to vary seating interface pressure. The results warrant continued investigation of EMS to assist in pressure sore prevention.