Cortical Stimulation to Improve Arm and/or Hand Function after Stroke Summary of Clinical Results to Date ADAMS and BAKER Clinical Studies

This is a brief summary intended to help answer questions about historical clinical results with cortical stimulation for the improvement of recovery of hand and/or arm function following stroke.

• Two clinical feasibility studies have been completed by Northstar Neuroscience and its clinical investigators (the ADAMS and BAKER studies). These studies were designed to test the safety and effectiveness of cortical stimulation (weak electrical current to the surface of the brain) on improving arm and hand function for stroke survivors at least 4 months after their stroke.

• A total of 32 patients completed both clinical studies. Half of the patients were in the "control groups," meaning that they received rehabilitative physical therapy only, without cortical stimulation. Half of the patients were in the "treatment groups," meaning they received the same rehabilitative physical therapy as the control patients, but with also receiving cortical stimulation at the same time.

• Patients in both groups benefited from participation in the study. However, those patients receiving cortical stimulation in addition to rehabilitative physical therapy on average benefited significantly more than those receiving physical therapy alone.

• In treatment group patients, benefit was demonstrated in the patients' scores on standardized tests of hand and arm function and in patients' ability to better accomplish activities of daily living. The patients improved hand and arm strength and dexterity.

• The amount of improvement varied from individual to individual but on average patients who received the implanted cortical stimulation system improved 15-30% as a result of participating in this study. Control group patients improved 0-12%.

• Those patients who received the implanted cortical stimulation system did not suffer serious complications from their surgeries or from the cortical stimulation.