Effect of functional neuromuscular stimulation on postural related orthostatic stress in individuals with acute spinal cord injury

The purpose of the study was to evaluate the cardiovascular responses of fu nctional neuromuscular stimulation (FNS) on postural-related orthostatic st ress in individuals with acute spinal cord injury. Two tetraplegics and thr ee paraplegics participated in this study. A repeated measure design was us ed in which subjects underwent two graded-tilt table (0 degrees, 15 degrees , 30 degrees, 45 degrees, 60 degrees) orthostatic stress tests with and wit hout FNS (randomized treatment order) of the knee extensors and foot planta r flexors. Successive one-minute digital readings of heart rate (HR) and bl ood pressure were obtained with an electronic pulse oximeter and automated blood pressure monitor, respectively. Analysis of covariance (ANCOVA) revea led significant test position (tilt angle) and treatment condition (with or without FNS) main effects, but no significant interactions. Between-treatm ent pairwise contrasts showed that systolic blood pressure was lower withou t FNS for 15 degrees, 30 degrees, 45 degreesg, and 60 degrees of tilt, whil e diastolic blood pressure was lower without FNS at 30 degrees and 45 degre es of tilt. In contrast, HR showed a progressive rise with increasing tilt angle. Functional neuromuscular stimulation may be an important treatment a djunct to minimize cardiovascular changes during postural orthostatic stres s in individuals with acute spinal cord injury.