Functional electrical stimulation (FES) of paralyzed muscles can facilitate walking after spinal cord injury (SCI).
To test the orthotic effects of different FES walking protocols on lower joint kinematics in individuals with incomplete SCI.
Three adults with motor incomplete SCI participated in this study. Their lower extremity motor scores [LEMS (left, right)] were as follows: subject A: 25/25, subject B:15/25, subject C:9/23. They were asked to randomly complete four conditions of overground walking in a 4-meter walkway (6-10 times/condition) including no FES, and three bilateral FES walking protocols as follows: drop-foot (tibialis anterior stimulation), flexor withdrawal (common peroneal nerve stimulation), and multi-muscle stimulation (stimulation of quadriceps and gastrocnemius in the stance phase, and hamstring and tibialis anterior in the swing phase). The FES system obtained gait phase information from the two footswitches located under the individuals’ feet. Three-dimensional kinematic analysis was undertaken to measure minimum toe clearance (MTC), ankle, and hip range of motion (ROM) using a 100 Hz eight infrared camera (Vicon Motion Systems, Oxford, UK).
The three FES-walking conditions significantly increased MTC compared to the no-FES condition in all participants. A significant decrease in ankle ROM was seen in the drop-foot (all subjects), multi-muscle (subjects A and C), and flexor withdrawal (subject A) stimulations. Hip ROM increased in the drop-foot (subjects B and C), flexor withdrawal (subject B), and multi-muscle (subject C) stimulations.
Three FES-walking protocols induced positive kinematic changes (increased hip flexion and toe clearance) during walking in subjects with incomplete SCI.
