Effectiveness of dual-tDCS in combination with upper limb robotic-assisted rehabilitation: a randomised, double-blind, cross-over study

Dehem, Stéphanie [UCL] Gilliaux, Maxime [UCL] Lejeune, Thierry [UCL] Delaunois, Emmanuelle [UCL] Mbonda Chimi, Paul [UCL] Vandermeeren, Yves [UCL] Detrembleur, Christine [UCL] Stoquart, Gaëtan [UCL]

Background: The impact of transcranial Direct Current Stimulation (tDCS) is controversial in the neurorehabilitation literature. It has been suggested that tDCS should be combined with other therapy to improve their efficacy. Aim: To assess the effectiveness of upper limb robotic-assisted therapy (RAT) combined with real or sham-tDCS in chronic stroke patients. Methods: Twenty-one hemiparetic stroke patients were included in a randomised, controlled, double-blind, cross-over study. Each patient underwent two therapy sessions seven days apart in a randomised order: (1) 20 minutes of real dual-tDCS associated with RAT (REAL+RAT) and (2) 20 minutes of sham dual-tDCS associated with RAT (SHAM+RAT). Patient dexterity (Box & Block and Purdue Pegboard tests) and upper limb kinematics were evaluated before and just after each intervention. The assistance provided by the robot during the intervention was also recorded. Results: Gross manual dexterity (1.8 +/- 0.7 blocks, p=0.008) and straightness of movement (0.01 +/- 0.03, p<0.05) improved slightly after REAL+RAT compare to before the intervention. There was no improvement after SHAM+RAT. The post-hoc analyses did not objectify difference between interventions: REAL+RAT and SHAM+RAT (p>0.05). The assistance provided by the robot was similar during the two interventions (p>0.05). Conclusion: The results demonstrated a slight improvement in hand dexterity and arm movement after the REAL+RAT tDCS intervention. The observed effect after one session was small and not clinically relevant, but repetitive sessions could increase the benefits of this combined approach.