Transcutaneous spinal cord stimulation combined with activity-based therapy leads to sensorimotor improvements in chronic, thoracic spinal cord injuries – a pilot study

Abstract Conclusion: Sub-threshold thoracolumbar tSCS facilitates recovery of trunk sensorimotor function in individuals with chronic SCI. Improvements required at least 60 tSCS-ABT sessions, with further exposure to tSCS facilitating continued improvements in function. These findings demonstrate that prolonged training with tSCS-ABT is an effective neuromodulation intervention for individuals with SCI. Study Design: Clinical trial Objective: Evaluate the efficacy of prolonged treatment with transcutaneous spinal cord stimulation (tSCS) in individuals with chronic spinal cord injury (SCI). Setting: Community-based neurorehabilitation centers in United Kingdom. Methods: Five participants with chronic, thoracic SCI completed 120 activity-based therapy sessions combined with sub-threshold tSCS delivered over the thoracolumbar spine (tSCS-ABT). Sensorimotor changes were assessed using NeuroRecovery Scale (NRS) at baseline and every 20 sessions, and International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) at baseline, 40 and 120 sessions. Results: NRS-Total and NRS-Trunk scores significantly improved following 120 sessions of tSCS-ABT (∆1.1 (95% CI 0.2–1.9) and ∆2.3 (95% CI 1.2–3.3], respectively), with these improvements dependent upon training dosage (F1.460, 5.840 =7.573, p=0.028, η2=0.65, F2.045, 8.180 =10.571, p=0.005, η2=0.73, respectively). Consistent with these findings, improved ISNCSCI sensation to pinprick (Δ2.8 (1.9), (95% CI 0.4–5.2), p<0.05) and light touch (Δ1.8 (0.8), (95% CI 0.8–2.8), p<0.01) were observed only after 120 tSCS-ABT sessions. Three individuals demonstrated improved ASIA Impairment Scale (AIS) classifications (A to C; B to C; C to D), with three individuals also demonstrating changes in level of injury (T6 to T11; T10 to T11; T10 to T11).