Comparative Outcomes of Epidural Spinal Cord Stimulation Near the Conus in Cervical vs. Lower Spinal Cord Injuries

Introduction: Spinal cord injuries (SCI) often lead to permanent sensorimotor impairments, affecting a significant number of individuals, including veterans. Although epidural spinal cord stimulation (eSCS) has shown promise in restoring function in SCI patients, the exploration of potential differences in surgical outcomes for patients with cervical, lumbar, and thoracic SCI has yet to be published.

Methods: To investigate the outcomes of SCI patients with eSCS implants, we conducted a descriptive analysis focusing on patient-reported outcomes via phone or video interviews and medical record reviews. Patients who had undergone eSCS by the primary investigator were selected for initial review.

Results: Of the 51 patients identified, 26 patients had injuries to their cervical spine, 1 lumbar, 23 thoracic, and 1 unknown. For comparative analysis, patients were grouped into Cervical Injuries, occurring between C1 and C7 inclusive (C; n=26, age at injury: 37.71±16.94) and Lower SCI, occurring between T1 and L1 inclusive (L; n=24, age at injury: 40.54±16.85). Patients in the C group had an average time of 7.37±9.27 years from injury to surgery, whereas the L group had an average time of 4.35±3.77 years. 59% of all patients experienced improvement in at least one modality (58% cervical, 63% lower). No follow-up information was found on 10 of the patients. Patients in each group experienced similar benefits of walking (C=7; L=6), standing (C=10; L=8), core function (C=5; L=4), upper limb control (C=1; L=N/A), bowel/bladder (C=7; L=10), spasticity (C=4; L=6), sleep (C=2; L=1), orgasm/arousal (C=2; L=2), pain (C=3; L=3), and quality of life improvements (C=2; L=0). An independent t-test indicated no statistically significant difference in benefits between the two groups (p=0.623).

Conclusion : Our data indicate that eSCS offers comparable benefits across different SCI locations with no significant difference in improvements, highlighting the potential of eSCS as a versatile modality for enhancing the quality of life in SCI patients, irrespective of injury level.