BIOMEDICAL ENGINEERING

Functional Electrical Stimulation (FES) facilitates ambulatory function after paralysis by activating the muscles of the lower extremities. Individuals with incomplete spinal cord injury (iSCI) retain some control of the partially paralyzed muscles, necessitating careful integration of functional electrical stimulation (FES) with intact motor function. In this study, the volitional surface electromyogram (EMG) from partially paralyzed muscle was used by a classifier to detect the intent to step in two volunteers with iSCI. The classifier was able to trigger the FES-assisted swing phase with a false positive rate less than 1% in both the subjects. The true positive rate was 82% for left foot-off and 83% for right foot-off for subject 1 and 96% for left foot-off for subject 2.

It was postulated that EMG being a more natural command source than manual switches will enable better coordination of stimulated and volitional motor function necessary during gait. This was investigated in the two volunteers with iSCI during the over-ground FES-assisted gait initiation. Four able-bodied volunteers provided the normative data for comparison. The EMG-triggered FES-assisted gait initiation was found to be more coordinated and dynamically more stable. This highlighted the potential of surface EMG from partially paralyzed muscles as a natural command interface to better coordinate stimulated and volitional muscle activities during gait.

Research Advisor: Dr. Ronald Triolo
Academic Advisor: Dr. Robert Kirsch