A growing body of evidence supports the effectiveness of transcranial direct current stimulation (tDCS) in rehabilitation of patients with hand motor impairment in the chronic phase of stroke. Furthermore, it is assumed that the combination of stimulation- and practice-induced plasticity may be especially beneficial. Aim is to compare the combined effects of anodal tDCS and specific motor training (MT) to sham tDCS and MT (control) on hand motor deficit in patients with chronic stroke.

A total of 30 patients were randomly assigned to an active treatment group (real tDCS+MT) or a control group (sham tDCS+MT) in this parallel, two-arm, double-blind, sham-controlled study. MT was administered for 45min/day (10 sessions) and preceded by 20minutes of either 2mA anodal tDCS or sham tDCS over the ipsilesional primary motor cortex. A modified Jebsen–Taylor Hand Function Test (mJTt) was the primary outcome measure, with handgrip dynamometer and upper limb Fugl–Meyer (ULFM) assessments as secondary outcomes. A subset of 21 patients was additionally evaluated by transcranial magnetic stimulation measures of the primary motor cortex excitability

The ANCOVA, controlling for baseline status (T0), showed a statistically significant time×group interaction for mJTt due to a statistically significant change over time in the active tDCS group compared to the sham tDCS group. In the active tDCS group, the mJTt time was significantly shorter both at the end of treatment (T2 vs. T0, decrease of 35.36±22.90 s or 28.42±14.56%) and at the follow-up (T3 vs. T0, decrease of 24.21±24.66 s or 19.98±17.49%). The active motor threshold decreased and the MEP amplitude increased.

Our findings suggest that hand motor deficits in chronic stroke survivors can be reduced when intensive MT is primed with anodal tDCS over the ipsilesional primary motor cortex.