Epidural Spinal Cord Stimulation Mapping: Targeted Restoration of Volitional Movements and Autonomic Function in Patients with Spinal Cord Injury

Introduction: Epidural spinal cord stimulation (eSCS) has been shown as a promising modality for restoring motor and autonomic functions in spinal cord injury (SCI) patients. Optimizing stimulator parameters and electrode configurations to enhance therapeutic outcomes is a critical yet underexplored area of research. Our study focuses on establishing a correlation between specific eSCS settings and therapeutic benefits.

Methods: Stimulator settings were collected in PulseShare.org, a web-based database we designed for secure communication with all personal health information de-identified to maintain confidentiality. Each parameter setting was evaluated via phone or video interviews. Welch’s t-tests were conducted to test for significant differences between average parameters (pulse frequency and width) that showed improvements in walking, standing, core stability, spasticity, bowel and bladder function versus those that did not. We also visually examined the average electrode configuration for each outcome among programs, which showed improvement.

Results: Of the 51 patients, 61% (31 patients) reported at least one type of functional improvement after eSCS. Notably, a pulse frequency difference of 16.47 Hz resulted in improvements for walking (p < 0.01), 18.46 Hz for standing (p < 0.01), and 18.66 Hz for reduced spasticity (p < 0.05). A pulse frequency and width difference of 23.95 Hz (p < 0.0001) and 96.72 µs (p < 0.05) also resulted in increased core stability. An electrode configuration with central cathodes near the stimulator’s base and anodes at the top showed a correlation with improved bowel and bladder functions.

Conclusion : Here, we demonstrate the potential of eSCS optimization to yield targeted functional recovery in patients with SCI.