Upper and Lower Body Coordination in FES-Assisted Sit-to-Stand Transfers in Paraplegic Subjects - A Case Study

Abstract : The objective of the work presented is to improve functional electrical stimulation (FES) assisted sit-to-stand motion in complete paraplegic individuals by restoring coordination between the upper part of the subject's body, under voluntary control, and the lower part of the body, under FES control. The proposed approach is based on the observation of trunk movement during rising motion and a detection algorithm, which triggers a pre-programmed stimulation pattern. We present a pilot study carried out on one T6 paraplegic subject. We validated the ability of the subject to produce repeatable trunk acceleration during sit-tostand transfers under FES and, the ability of the system to trigger the stimulator at the desired instant in time. We also analyzed the influence of the timing of leg stimulation, relative to the trunk acceleration profile, on upper limb efforts applied during sit-to-stand motion.