tDCS does not enhance the effects of robot-assisted gait training in patients with subacute stroke

Background: Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique, which can modulate cortical excitability and combined with rehabilitation therapies may improve motor recovery after stroke. Objective: Our aim was to study the feasibility of a 4-week robotic gait training protocol combined with tDCS, and to study tDCS to the leg versus hand motor cortex or sham to improve walking ability in patients after a subacute stroke. Methods: Forty-nine subacute stroke patients underwent 20 daily sessions (5 days a week for 4 weeks) of robotic gait training combined with tDCS. Patients were assigned either to the tDCS(leg) group (n = 9), receiving 2mA anodal tDCS over the motor cortex leg representation (vertex), or an active control group (n = 17) receiving anodal tDCS over the hand motor cortex area (tDCS(hand)). In addition, we studied 23 matched patients in a control group receiving gait training without tDCS ((no)tDCS). Study outcomes included gait speed (10-meter walking test), and quality of gait, using the Functional Ambulatory Category (FAC) before and after the 4-week training period. Results: Only one patient did not complete the treatment because he presented a minor side-effect. Patients in all three groups showed a significantly improvement in gait speed and FAC. The tDCS(leg) group did not perform better than the tDCS(hand) or (no)tDCS group. Conclusion: Combined tDCS and robotic training is a safe and feasible procedure in subacute stroke patients. However, adding tDCS to robot-assisted gait training shows no benefit over robotic gait training alone.