Cortical stimulation for upper limb recovery following ischemic stroke: A small phase II pilot study of a fully implanted stimulator

Objective: To evaluate the feasibility of a fully implanted cortical stimulator for improving hand and arm function in patients following ischemic stroke. Method: Twenty-four chronic stroke patients with hemiplegia were randomized to targeted implanted cortical electrical stimulation of the motor cortex with upper limb rehabilitation therapy or rehabilitation therapy alone. Results: Using repeated measures regression models, we estimated and compared treatment effects between groups over the study follow-up period. The investigational group had significantly greater mean improvements in Upper Extremity Fugl-Meyer (UEFM) scores during the 6-month follow-up period (weeks 1-24 following therapy), as compared to the control group (difference in estimated means = 3.8, p = .042). Box and Block (B & B) test improvement from baseline scores were also significantly better in the investigational group across the 6-month follow-up assessments (difference in estimated means = 3.8, p = .046). There was one report of seizure after device implant but prior to cortical stimulation and rehabilitation therapy, but no reports of neurologic decline. There were no improvements seen in the other measures assessed. Conclusion: Evidence suggests that cortical stimulation with rehabilitation therapy produces a lasting treatment effect in upper extremity motor control and is not associated with serious neurological complications. A larger multicenter study is underway.