Background. Stroke survivors often present poor upper-limb (UL) motor performance and reduced movement quality during reaching tasks. Transcranial direct current stimulation (tDCS) and functional electrical stimulation (FES) are widely used strategies for stroke rehabilitation. However, the effects of combining these two therapies to rehabilitate individuals with moderate and severe impairment after stroke are still unknown.

Objective. Our primary aim was to evaluate the effects of concurrent bi-cephalic tDCS and FES on UL kinematic motor performance and movement quality. Our secondary aim was to verify the effects of the combined therapies on handgrip force and UL motor impairment.

Methods. We randomized 30 individuals with moderate and severe chronic hemiparesis after stroke into tDCS plus FES (n=15) and sham tDCS plus FES (n=15) groups. Participants were treated 5 times a week for 2 weeks. Kinematic UL motor performance (movement cycle time, velocity profile) and movement quality (smoothness, trunk contribution, joint angles), handgrip force and motor impairment were assessed before and after the intervention.

Results. For those participants allocated to the tDCS plus FES group, therapy was effective to improve movement cycle time (p=0.039), mean reaching phase velocity (p=0.022) and handgrip force (p=0.034). Both groups showed improved mean returning phase velocity (p=0.018), trunk contribution (p=0.022), and movement smoothness (p=0.001) as well as alleviated UL motor impairment (p=0.002).

Conclusions. Concurrent bi-cephalic tDCS and FES slightly improved reaching motor performance and handgrip force of individuals with moderate and severe UL impairment after stroke.