Overview

The goal of this clinical trial is to evaluate the safety and effectiveness of Epidural Electrical Stimulation (EES) combined with rehabilitation training for the reconstruction of walking in patients with chronic spinal cord injury (SCI) classified as AIS C-D. The main questions it aims to answer are:

Does the intervention of EES combined with rehabilitation significantly improve walking capacity? Is the combined intervention a safe approach for this patient population? Researchers will compare participants' functional assessments before EES implantation and at 1, 3, 6, 9, and 12 months post-implantation to evaluate the longitudinal effects. The primary assessments include the Walking Index for Spinal Cord Injury II (WISCI II), the 10-Meter Walk Test (10mWT), and the 6-Minute Walk Test (6minWT). Secondary outcome measures encompass the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI), the Spinal Cord Independence Measure (SCIM III), the Functional Independence Measure (FIM), the Modified Ashworth Scale (MAS), the Penn Spasm Frequency Scale, and pain Visual Analogue Scale (VAS) scores. Neurophysiological and imaging evaluations, including electromyography (EMG), motor evoked potentials (MEPs), somatosensory evoked potentials (SEPs), and positron emission tomography-computed tomography (PET-CT), will be conducted preoperatively and at 6 months postoperatively to explore the mechanisms of neuroplasticity.

Participants will:

Undergo surgical implantation of an EES device. Receive personalized EES parameter programming combined with rehabilitation training (≥2 hours daily) post-operatively.

Complete a series of standardized functional and clinical outcome assessments at scheduled follow-up intervals.

Undergo scheduled neurophysiological and metabolic imaging studies. Report any adverse events throughout the study duration.

Eligibility

Inclusion Criteria:

• Age between 16 and 65 years.
• Diagnosed with traumatic spinal cord injury for ≥ 6 months and ≤ 36 months.
• American Spinal Injury Association Impairment Scale (AIS) grade C-D.
• Spinal cord injury level above T10;
• Walking Index for Spinal Cord Injury II (WISCI II) score \< 13.
• Completion of a standard conventional rehabilitation program prior to enrollment.
• Preserved upper limb function sufficient for self-propelling a manual wheelchair.
• Sitting balance grade ≥ 1.
• Ability to elicit clear electromyographic responses in lower limb muscles (e.g., rectus femoris, biceps femoris, gastrocnemius, tibialis anterior) upon transcutaneous electrical spinal cord stimulation at the T12-L1 vertebral levels.
• Willingness to voluntarily participate, and commitment to compliance with all necessary postoperative rehabilitation, assessments, and follow-up visits.

Exclusion Criteria:

• History of myocardial infarction or stroke within the past 6 months.
• Diagnosis of psychiatric disorders with active suicidal ideation or risk.
• Current pregnancy or planned pregnancy during the study period.
• Bleeding tendency or coagulopathy (prothrombin time ≥18 seconds).
• History of alcohol or substance abuse or dependence.
• Intellectual disability, cognitive impairment, or personality disorders.
• Other chronic medical conditions that may interfere with rehabilitation (e.g., unhealed severe fractures, hepatic or renal failure, severe anemia, etc.).
• Implantation of cardiac pacemakers, cardioverters, or defibrillators.
• Any other condition deemed inappropriate for participation by the investigators.