Closed-Loop SCS-BCI for Post-Stroke Hemiplegia

This study evaluates a new closed-loop rehabilitation system for stroke survivors with arm weakness. The system combines a brain-computer interface (BCI, a special cap that reads brain signals), spinal cord stimulation (a temporary implanted electrode that sends gentle electrical pulses to the spine), and a robotic hand exoskeleton. When the participant imagines moving their affected hand, the system detects this intention from brain signals and immediately triggers the spinal stimulation and robotic assistance to help complete the movement. The goal is to test whether this "brain-spine-hand" closed-loop approach is safe and can improve upper limb function after stroke. About 30 stroke patients with chronic arm weakness will be enrolled. Participants will first undergo brain signal testing to confirm they can produce detectable movement intentions. Eligible participants will then have a temporary spinal cord stimulator electrode placed under the skin near the spine. Over the next 4 weeks, they will receive daily training sessions (about 90 minutes, 5 days per week) using the closed-loop system. After 4 weeks, the electrode will be removed, and participants will continue standard rehabilitation. Hand and arm function will be assessed before, during, and after the intervention.

Inclusion Criteria: * Age 18-60 years. * Unilateral upper limb motor dysfunction due to primary stroke. * Stable brain lesion and underlying etiology. * Upper limb motor dysfunction for \>6 months with no recent improvement despite standardized rehabilitation (plateau phase). * Detectable wrist/finger extension motor intention (pre-activation recordable by sEMG). * Upper extremity Fugl-Meyer Assessment score 10-42 (moderate to severe). * Affected major muscle strength ≥ grade 1. * Normal hearing and language comprehension; able to cooperate with training. * Mini-Mental State Examination (MMSE) score ≥ 22. * Signed informed consent. Exclusion Criteria: * Active infection, fever, or unstable vital signs/intracranial condition. * Need for MRI during device implantation period. * Hypotonic or flaccid paralysis of affected limb. * Other causes of motor dysfunction (e.g., ALS, myasthenia gravis, muscular dystrophy, hypokalemic periodic paralysis, spondylitis, arthritis, osteomyelitis). * Severe sports injury or surgical history of affected limb (e.g., muscle tear, tendon rupture, rhabdomyolysis). * Severe pain or musculoskeletal deformity affecting training. * Previous cervical/thoracic spine surgery, severe spinal deformity, or severe spinal stenosis precluding SCS electrode placement. * Severe comorbidities (e.g., epilepsy, malignancy, severe cerebrovascular disease/brain tumor, uncontrolled or grade 3 hypertension, diabetes, heart disease, hepatic/renal insufficiency, electrolyte imbalance, coagulopathy, autoimmune disease, long-term use of drugs suppressing neuronal activity). * Confirmed psychiatric disorders (e.g., depression, anxiety, OCD, schizophrenia, autism, chronic sleep disorder, consciousness disorder). * Implanted electronic devices (e.g., cochlear implant, pacemaker/ICD, drug pump). * Pregnancy, breastfeeding, or planning pregnancy within 3 months. * Participated in other clinical trials within past month or currently participating. * Poor compliance of participant, family, or caregiver. * Other conditions deemed unsuitable by surgeon/investigator.