The Immediate Effect of Electrical Stimulation Transcranial Direct Current (tDCS) Associated With the Use of FES, in Muscle Activity of the Tibialis Anterior Muscle, Balance and Plantar Pressure Distribution of Individuals With Hemiparesis Due to Stroke

The Immediate Effect of Electrical Stimulation Transcranial Direct Current (tDCS) Associated With the Use of FES, in Muscle Activity of the Tibialis Anterior Muscle, Balance and Plantar Pressure Distribution of Individuals With Hemiparesis Due to Stroke - Randomized, Double Blind

Background: Transcranial direct current stimulation (tDCS) is currently considered a beneficial method for patients with neurological problems due to the modulation of cortex activity as well as the enhancement and prolongation of functional gains achieved during physical therapy. Purpose: The aim of the proposed study is to evaluate the immediate effects of a session of tDCS over the primary motor cortex combined with functional electrical simulation (FES) on electrical activity of the tibialis anterior muscle, balance and distribution of plantar pressure in individuals with hemiparesis stemming from a stroke. A further aim is to determine whether the effects of the combination of both stimulation methods are better than those achieved when each method is employed alone. Methods/design: A randomized, double-blind, crossover, cross-sectional study will be conducted involving 30 stroke survivors with hemiparesis who meet the eligibility criteria. Evaluations will involve an identification and screening chart, the classification of motor impairment using the Fugl-Meyer Scale, the determination of spasticity of the triceps surae muscle (modified Ashworth scale), electromyography of the tibialis anterior muscle, static balance and cognitive dual-task balance (stabilometry) and plantar pressure. After the initial evaluations, the participants will undergo four interventions: 1) anodal tDCS + placebo FES + active tibialis anterior contraction; 2) placebo tDCS + active FES + active tibialis anterior contraction; 3) anodal tDCS + active FES + active tibialis anterior contraction; and 4) placebo tDCS + placebo FES placebo + active tibialis anterior contraction. tDCS will be administered over the primary motor cortex and FES will be administered over the tibialis anterior muscle. The order of the different protocols will be randomized and both the evaluator and patients will be blinded to which protocol is being administered.

Inclusion criteria:

• 30 individuals with hemiparesis stemming from a stroke;
• Either gender;
• Able to maintain a standing position without an assistance device for at least 60 seconds;
• Signed statement of written consent.

Exclusion criteria:

• Adverse health condition (beyond hemiparesis) that affects balance;
• Use of medication that can affect balance;
• Positive cutoff point for cognitive deficit (Mini Mental State Examination);
• Illiteracy;
• Wernicke's aphasia;
• Reduced ankle mobility due to history of ankle fracture and use of pins in ankle;
• TA muscle strength less than grade 1;
• Contraindication for tDCS (history of recurrent seizures, recurrent epilepsy and brain tumor in stimulation site);
• Skin infection at tDCS and/or FES site;
• Anesthesia or hyperesthesia at FES site.