Functional Electrical Stimulation for Footdrop in Hemiparesis

Hemiplegia is a major consequence of stroke and contributes significantly to the physical disability of stroke survivors. Foot-drop, or inability to dorsiflex the paretic ankle during the swing phase of gait, and ankle instability during stance phase, are important gait abnormalities that contribute to reduced mobility among stroke survivors. In the United States, the standard of care in addressing these deficits is the custom molded ankle-foot-orthosis (AFO). However, evolving data now demonstrate that active repetitive movement training is the principal substrate for facilitating motor relearning after stroke. Motor relearning is defined as the reacquisition of motor ability after central nervous system injury. Thus, while an AFO may assist stroke survivors to ambulate in the short-term, it is possible that it also inhibits recovery in the long-term. Previous studies have demonstrated that active repetitive movement exercises mediated by neuromuscular electrical stimulation (NMES) facilitate motor relearning among stroke survivors. In particular, studies have reported that some chronic stroke survivors treated with a peroneal nerve stimulator for foot-drop experience sufficient recovery that they no longer need the peroneal nerve stimulator or an AFO for community ambulation. However, there are no blinded randomized clinical trials that rigorously evaluate the motor relearning effects of ambulation training with peroneal nerve stimulators. Thus, the primary aim of this project is to assess the effects of transcutaneous peroneal nerve stimulation on lower limb motor relearning among chronic stroke survivors. The secondary aim is to assess the effects of transcutaneous peroneal nerve stimulation on lower limb mobility (disability) and overall quality of life. A single-blinded randomized clinical trial will be carried out to assess the effects of ambulation training with a peroneal nerve stimulator among chronic stroke survivors compared to ambulation training with conventional standard of care (which may include an AFO). Subjects will be treated for 12 weeks and followed for a total of another 6 months. This project will determine the effectiveness of peroneal nerve stimulation in facilitating motor relearning and improving the mobility and quality of life of stroke survivors. This proposed approach is expected to improve patient outcome and challenge the present clinical paradigm of prescribing AFOs for stroke survivors with foot-drop.