The goal of the study is to explore the effect of combined training involving functional electrical stimulation (FES) of the ankle dorsal flexor with simultaneous maximal-effort voluntary contraction of the same muscle to correct or improve foot drop in chronic stroke patients. Participants will be assessed for functional motor ability and neurological function during their first visit and then again after five and then ten weeks of training. Functional motor ability is broken down into dorsiflexion strength and general gait analysis. Dorsiflexion strength is measured by use of a dynamometer. Gait is assessed via recordings of electromyography, pedobarography, kinematic, and various functional variables during 10 walking trials. The neurological assessment will include electroencephalographic (EEG) analysis of movement-related cortical potentials (MRCP), somatosensory evoked potentials (SSEP), and M-wave response to stimulation. Participants will be randomly assigned to one of three groups: 1) FES + volitional movement (VOL), 2) FES alone, and 3) VOL alone, which will determine their training regimen. The training sessions involve roughly 20 minutes of repeated muscle contractions (with appropriate breaks to avoid fatigue). The participants assigned to the FES+VOL group will receive electrical stimulation to the peroneal nerve in concert with volitional dorsiflexion, whereas the other groups will either dorsiflex voluntarily with no stimulation or receive stimulation while being asked to do nothing.
- FES Device
Intervention Desc: Electrical stimulation is applied to the subject while they are asked to do nothing. ARM 1: Kind: Experimental Label: FES Description: Electrical stimulation alone. The subject is asked to do nothing as electrical stimulation initiates and completes the movement for them.
- FES + VOL Other
Intervention Desc: Electrical stimulation is applied in concert with the subject's volitional movement. ARM 1: Kind: Experimental Label: FES+VOL Description: Electrical stimulation (FES) in concert with volitional effort. The subject is visually cued to initiate the movement and when they begin the movement (as ascertained by EMG response), the stimulation is immediately applied until the completion of the trial.
- VOL Other
Intervention Desc: The subject initiates and completes the movement without electrical stimulation. ARM 1: Kind: Experimental Label: VOL Description: Volitional effort alone. When cued, the subject initiates and completes the movement on their own until the completion of the trial. There is no electrical stimulation in this group.
- Allocation: Randomized
- Masking: Open Label
- Purpose: Treatment
- Endpoint: Efficacy Study
- Intervention: Parallel Assignment
|Type||Measure||Time Frame||Safety Issue|
|Primary||Force Produced by Voluntary Dorsiflexion||Change from baseline to 0 weeks post-intervention and from baseline to 5 weeks post-intervention||No|
|Primary||Time to Complete 10 Meter Walk||Change from baseline to 0 weeks post-intervention and from baseline to 5 weeks post-intervention||No|
|Primary||Center of Pressure of Plantar Loading During Walking Trial||Change from baseline to 0 weeks post-intervention and from baseline to 5 weeks post-intervention||No|
|Primary||Joint Angles During Walking Trial||Change from baseline to 0 weeks post-intervention and from baseline to 5 weeks post-intervention||No|
|Primary||Amplitude of the Major Components of Somatosensory Evoked Potentials||Change from baseline to 0 weeks post-intervention and from baseline to 5 weeks post-intervention||No|
|Primary||Amplitude of the P40-N50 Complex During Movement Related Cortical Potentials||Change from baseline to 0 weeks post-intervention and from baseline to 5 weeks post-intervention||No|
|Primary||Amplitude and Latency of M-Wave Component of EMG During Maximal Voluntary Contraction||Change from baseline to 0 weeks post-intervention and from baseline to 5 weeks post-intervention||No|
- Kessler Foundation Lead