300 Section - Dual-Site, Gait-synchronized Brain Stimulation Targeting Primary and Supplementary Motor Areas Improves Gait Variability in Post-Stroke Hemiparetic Patients

While walking speed is an important indicator of recovery in post-stroke hemiparesis, gait stability is more closely associated with fall risk and long-term decline. Interaction between the supplementary motor area (SMA) and primary motor cortex (M1) is crucial for post-stroke gait stability. Therefore, simultaneous activation of the SMA and gait-synchronized stimulation of the M1 may enhance gait stability compared with independent stimulation.

To evaluate the feasibility, safety, and preliminary effects of simultaneous SMA and M1 stimulation on gait variability and balance in individuals with post-stroke hemiparesis.

Design:

Sixteen individuals with a stroke within 180 days of onset, aged 40–90 years, who were able to walk on a treadmill, were recruited for this study. They were allocated to an intervention group (n=8) receiving 20 minutes of simultaneous transcranial direct current stimulation (tDCS) to the SMA and gait-synchronized rhythmic stimulation to the M1 during treadmill walking, or to a control group (n=8) receiving sham stimulation. Both groups completed 15 sessions of walking practice over 3 weeks. Primary outcomes included feasibility (recruitment, retention, adherence, adverse events) and preliminary effects on gait variability (coefficient of variation for stride, stance, and swing times on the paretic side). Balance was assessed using the Mini-Balance Evaluation Systems Test (Mini-BESTest).

Results:

All 16 participants completed the intervention without adverse events, indicating high feasibility. The intervention group showed significantly reduced stride time variability on the paretic side and improved Mini-BESTest scores compared to the control group. A significant correlation was observed between reductions in gait variability and improvements in balance.

Conclusion:

This pilot trial supports the feasibility and safety of combined SMA and M1 stimulation. Results suggest potential benefits for reducing gait variability and improving balance after stroke, warranting further investigation in a larger trial.