Reclaiming Motor Functions after Complete Spinal Cord Injury using Epidural Minimally Invasive Brain-Computer Interface

Spinal cord injuries significantly impair patients' ability to perform daily activities independently. While invasive brain-computer interfaces (BCIs) offer high communication bandwidth to assist and rehabilitate these patients, their invasiveness limits broader adoption. We developed a minimally invasive BCI system that balances safety and communication bandwidth to restore hand functions. This system enables real-time, precise control of hand movements and effective hand function rehabilitation, requiring less than 10 minutes of calibration time and maintaining an average grasping detection F1-score of 0.91 over a 9-month period of home use. A tetraplegia patient caused by complete spinal cord injury was recruited in this study. With the assistance of the brain-computer interface, the patient can successfully perform object grasping and daily tasks involving hand functions, achieving a 100% success rate in an object transfer test. Additionally, the patient showed substantial neurological recovery through consecutive BCI upper limb training, regaining the ability to hold objects without BCI assistance. The patient demonstrated a 5-point improvement in ISNCSCI upper limb motor scores and a 27-point increase in the Action Research Arm Test (ARAT). Improvements in electrophysiological assessments point to a considerable recovery in impaired neural circuits. The cerebral-spinal channels established via this BCI system offer a promising new approach for treating spinal cord injuries and restoring hand functions.