Neuromodulation of effects of upper limb motor function and shoulder range of motion by functional electric stimulation (FES).

Upper extremity motor impairment is a major contributing factor to functional disability of stroke patients. Functional electric stimulation (FES) is one of the therapeutic regimens for the management of upper extremity dysfunction after stroke. This review shows that therapeutic FES intervention on supraspinatus and posterior deltoid muscles for 6 weeks is effective to speed up upper limb motor recovery in hemiplegia of short-duration after stroke or less severely affected symptoms. The positive effect of FES could be attributable to neural mechanisms including: an enhanced information flow from the joint and muscle afferents, a better visual perception of the movement produced, and a stronger muscle contraction due to direct stimulation of the motor neuron. However, FES was demonstrated as not being effective in reducing the shoulder range of motion of external rotation in patients with either short- or long-duration hemiplegia. In order to offer better management in maintaining or improving limited shoulder range of motion, other types of electrical stimulation should be considered.