The study is designed to assess the role of functional neural regeneration collagen scaffold transplantation combined with epidural electrical stimulation in spinal cord injury patients.

Inclusion Criteria:

The enrolled participants are divided into three categories:

1. Participants had complete functional scaffold transplantation in previous study and had motor functional recovery
2. Participants With Acute Complete SCI: (1) Classification ASIA A, occurring within past 14 days; (2) Completely spinal cord injury at neurological level C4- T12/L1; (3) No serious complications
3. Participants With Chronic Complete SCI: (1) Classification ASIA A, greater than 6 months post injury and no significant further improvement within past 3 months; (2) Completely spinal cord injury at neurological level C4- T12/L1; (3) Peripheral nervous system in good condition; (4) No serious complications

Inclusion Criteria For All The Participants

1. Men or non-pregnant women, 18-60 years old
2. Ability and willingness to regular visit to hospital and follow up during the protocol Procedures
3. Accompanied by a family member
4. Signed informed consent

Exclusion Criteria:

1. Obvious muscle atrophy or fibrosis
2. Decline in peripheral nerve function
3. A current diagnosis of diseases affecting spinal cord injury recovery or rehabilitation training (e.g., brain injury, cerebral hemorrhage, cognitive impairment, other central nervous system diseases)
4. Having serious health problems, (e.g., cardiovascular disease, diabetes, autoimmune diseases, tumors or severe hypertension) or serious complications (e.g. severe bedsores, pulmonary infection, respiratory disorders)
5. Pregnancy or lactation
6. History of mental illness or suicide risk, with a history of epilepsy or other central nervous system disorders
7. No family member accompany or can not get in touch with family members
8. Poor compliance, difficult to complete the study
9. Any other conditions that might increase the risk of participants or interfere with the clinical trial