Immediate Effect of Transcranial Direct Current Stimulation Combined with Functional Electrical Stimulation on Plantar Distribution and Body Sway Frequency in a Patient with Hemiparesis from Stroke: A Case Report

Objectives: The present study aimed to evaluate the immediate effect of a single session of anodal transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) combined with functional electrical stimulation (FES) of the tibialis anterior (TA) muscle on plantar distribution and body sway frequency in an individual with hemiparesis stemming from a stroke. A further aim was to determine whether the effects of the combination of stimulation techniques would lead to greater improvement than the techniques administered separately.

Methods: The therapy was conducted with one 60-year-old male with right-side stroke and complete, but disproportional hemiparesis with brachial predominance on the left side, 42 months elapsed since the event and severe Fugl-Meyer score. The patient was submitted to four different randomly performed intervention protocols with a 48-hour intervention between sessions: 1) anodal tDCS + sham FES + active TA contraction; 2) sham tDCS + active FES + active TA contraction; 3) anodal tDCS + active FES + active TA contraction; 4) sham tDCS + sham FES + active TA contraction). TDCS was administered for 20 minutes with the anode over C4 and the cathode over the supraorbital region on the contralateral side and FES was administered over the left TA. The evaluation of plantar distribution was performed with a foot-pressure platform and body sway frequency was evaluated using a force plate before and after each protocol.

Results: Beneficial changes occurred in the area of contact of the left hindfoot and right forefoot following intervention protocols 1, 2 and 3 and a reduction in body sway frequency occurred under all data acquisition conditions after protocols 1 and 2.

Conclusion: The use of tDCS (combined and alone) and the use of FES contributed to improvements in plantar distribution and body sway frequency in a stroke survivor with hemiparesis. The use of tDCS either alone or combined with FES achieved better results than the use of FES alone.