The effects of electromyography-controlled functional electrical stimulation on upper extremity function and cortical perfusion in stroke patients

Objective

The relation was investigated between hemiparetic arm function improvement and brain cortical perfusion (BCP) change during voluntary muscle contraction (VOL), EMG-controlled FES (EMG-FES) and simple electrical muscle stimulation (ES) before and after EMG-FES therapy in chronic stroke patients.

Methods

Sixteen chronic stroke patients with moderate residual hemiparesis underwent 5 months of task-orientated EMG-FES therapy of the paretic arm once or twice a week. Before and after treatment, arm function was clinically evaluated and BCP during VOL, ES and EMG-FES were assessed using multi-channel near-infrared spectroscopy.

Results

BCP in the ipsilesional sensory-motor cortex (SMC) was greater during EMG-FES than during VOL or ES; therefore, EMG-FES caused a shift in the dominant BCP from the contralesional to ipsilesional SMC. After EMG-FES therapy, arm function improved in most patients, with some individual variability, and there was significant improvement in Fugl–Meyer (FM) score and maximal grip strength (GS). Clinical improvement was accompanied by an increase in ipsilesional SMC activation during VOL and EMG-FES condition.

Conclusion

The EMG-FES may have more influence on ipsilesional BCP than VOL or ES alone.

Significance

The sensory motor integration during EMG-FES therapy might facilitate BCP of the ipsilesional SMC and result in functional improvement of hemiparetic upper extremity.