Effects of regular use of neuromuscular electrical stimulation on tissue health

Changes in tissue health were monitored in a group of spinal cord injury (SCI) individuals with the use of an implanted neuromuscular electrical stimulation (NMES) system to provide standing and to facilitate standing transfers. Tissue health was evaluated through monitoring tissue oxygen levels in the ischial region along with measuring interface pressures at the seating support interface. Baseline assessments were done at study enrollment and repeated on completion of a conditioning exercise program. Serial assessments of tissue health were performed on eight NMES implant recipients. Unloaded tissue oxygen levels in the ischial region tended to increase after following the NMES exercise program for 8 weeks. Concurrently, pressure distributions at the seating support interface tended to change such that although the total pressure acting at the interface did not change, ischial region pressures showed a significant decrease. These changes indicate that chronic use of NMES has a quantifiable benefit on tissue health. tend to produce increased interface pressures in the region of the ischial tuberosities when individuals are sitting. Regional blood flow will be also affected by motor paralysis. In normal functional muscle, regular muscular contractions act to facilitate regional blood flow by "pumping" blood through the vascular network. This blood pump mechanism is no longer effective below the level of the lesion in individuals with SCI. Following SCI, sympathetic nervous activity below the level of the lesion decreases, leading to decreased blood pressure [ 1,2]. Vascular patency is adversely affected such that the vessels are less capable of withstanding normal loading conditions and maintaining blood flow [3]. Concurrent with loss of muscle bulk, a loss of capillary network will occur, thus reducing the volume of blood that can be delivered to the tissues even under optimal conditions.