NIBS Therapy in Subacute Spinal Cord Injury

Overview

No accepted clinical therapies exist for repair of motor pathways following spinal cord injury (SCI) in humans, leaving permanent disability and devastating personal and socioeconomic cost. A robust neural repair strategy has been demonstrated in preclinical studies, that is ready for translation to recovery of hand and arm function in human SCI, comprising daily transcranial magnetic stimulation treatment at the inpatient rehabilitation facility. This study will establish clinical effect size of the intervention, as well as safety and feasibility necessary for a subsequent controlled efficacy trial and inform preclinical studies for dosing optimization.

The objective of this proposal is to begin translating findings from pre-clinical studies to human motor deficits following cervical SCI (cervSCI). This HF-rTMS treatment protocol has not been previously assessed in human SCI and is qualitatively different from rTMS protocols reported to transiently modulate excitability of existing pathways, previously demonstrated in the literature. The protocol involves a daily stimulation of \~10 mins bilateral HF-rTMS for 2 weeks. SCI participants will be studied in a United States inpatient setting for this phase I study. Given the findings in the pre-clinical model of robust axonal sprouting and functional synapse formation close to the damaged tissue using the above stimulation parameters, the transcranial magnetic stimulation treatment will target the hand-forearm region of the primary motor cortex, bilaterally. The aim is to include the cortical representation of affected muscles adjacent to the neurological level of injury. This zone often contains a mix of clinically and neurophysiologically intact, weakly innervated and denervated corticospinal pathways. Under standard sub-acute rehabilitation care, recovery of up to 1 neurological level of injury (NLI) is often the case, but improvement of 2 or more levels is far less common (\<30% of patients). To examine the feasibility and safety of this novel intervention is the principal aim of the study. The associated potential clinical and neurophysiological changes will also be evaluated. These preliminary data will be used to power a subsequent efficacy trial to test the hypothesis that rTMS induced corticospinal augmentation will result in greater than typical extension of the NLI in human SCI, assessed up to the stable recovery phase at 6 months post-injury.