This is an open-label single-arm clinical study conducted at designated clinical trial institutions, with three overall phases: a 3-month main study, a 3-month extension, and a 3-month follow-up. The main study includes screening/baseline, preoperative preparation, surgery, upper limb rehabilitation adjustment, and pneumatic hand function training-specifically, preoperative brain and spinal cord imaging for electrode placement in eligible subjects, implantation of high-channel electrodes, and postoperative combined rehabilitation to build a motor intention decoding model that drives the pneumatic hand to grasp. The extension phase focuses on precise assessment of upper limb grasping function, signal stability monitoring, implantation of epidural spinal cord test electrodes, and closed-loop regulated epidural electrical stimulation for limb rehabilitation using implanted intracranial electrode signals. The follow-up phase involves intracranial electrode removal, implantation of long-term epidural spinal cord electrodes, and limb rehabilitation training and observation based on scalp EEG signals.

Inclusion Criteria:

• 18-65 years old (no gender restriction)
• Clinically diagnosed with tetraplegic motor dysfunction following brainstem or spinal cord injury
• ≥ 6 months after brainstem or spinal cord injury, with stable condition (spinal shock phase has passed, and no significant improvement or deterioration in sensory and motor function)
• Bilateral upper limb muscle strength ≤ Grade 2 and bilateral lower limb muscle strength ≤ Grade 3 by Manual Muscle Testing (MMT)
• Cognitive function: Mini-Mental State Examination (MMSE) score ≥ 20

Exclusion Criteria:

• Females who are pregnant
• History of drug abuse or alcoholism
• Diseases that limit limb mobility: fractures (progressive/deformity-causing fractures), hip dysplasia and other diseases causing limited hip mobility, diabetic foot, severe osteoporosis, limb joint contracture deformity, spasticity, and hospitalization due to autonomic dysreflexia in the past 3 months
• Neurological diseases/injuries: traumatic brain injury, epilepsy, neurodegenerative diseases or neuropathies, severe anxiety or depression, and suicidal ideation
• Surgical contraindications: infectious diseases; unstable angina pectoris, severe arrhythmia, and other heart diseases; immune system diseases and major organ diseases; coagulation disorders and bleeding tendencies; ankylosing spondylitis; malignant tumors; spinal instability and spinal stenosis
• BMI ≥ 30.0 kg/m²
• Patients with depressive disorder (17-item Hamilton Depression Rating Scale [HAMD] score > 17)
• Patients unable to comply with the study protocol

IPD (Individual Participant Data) contains individual information of participants (such as demographic characteristics, medical history, examination results, and intervention responses). Even after the "de-identification process", there remains a risk that the participants' identities could be inferred through cross-validation (e.g., by combining regional, age, and disease characteristics).

Compliance with global privacy protection regulations-such as China's Personal Information Protection Law-is required, as these regulations clearly stipulate that "individual sensitive medical data shall not be disclosed unless necessary" to prevent infringement of rights and interests (such as discrimination and identity abuse) caused by privacy leaks.