Evaluating Electrical Activity of Tibialis Anterior Muscle and Balance in Hemiparetic Patients Following Central and Peripheral Electrical Stimulation - Protocol for a Randomized, Double-blinded, Clinical Trial

Concomitant transcranial direct current stimulation (tDCS) is suggested to enhance the functional effects of other physical rehabilitation methods in individuals with motor impairment stemming from a chronic cerebrovascular disease. Thus, the primary aim of the proposed study is to analyze the electrical activity of the tibialis anterior (TA) muscle of the paretic limb in stroke survivors following an intervention involving the combination of tDCS over the motor cortex and peripheral electrical stimulation (PES) administered over the paretic TA. The secondary objective is to analyze the effect on dynamic balance.

Methods: Thirty-six adult stroke survivors will be randomized into three groups: 1) Active tDCS + active PES; 2) Sham tDCS + active PES and 3) Active tDCS + sham PES. TDCS active will be positioned bilateral over the primary motor cortex of the damaged hemisphere (C1 or C2) and the cathode will be positioned over the primary motor cortex of the undamaged hemisphere (C1 or C2) with a current of 2 mA for 20 minutes. For sham tDCS, will follow the same standarts, however, the equipment will be switched on for only 20 seconds. PES will be administered to the paretic TA at 50 Hz for 30 minutes. Evaluations: the median frequency and root mean square (RMS) of the paretic TA will be analyzed using electromyography (EMG) and dynamic balance will be evaluated using the Mini-Balance Evaluation System (Mini-BESTest) at baseline (pre-intervention), after 10 treatment sessions at a frequency of five times a week for two weeks (post-intervention) and 30 days after the end of the interventions (follow up).

Discussion: PES has proven to facilitate the conduction of sensory-motor afferences to the cerebral cortex in stroke survivors. Combining PES with tDCS, which has a direct effect on increasing cortical excitability, could favor motor acquisition and neuronal plasticity in this population.