Transcutaneous Spinal Cord Stimulation for Upper Extremity Function

Phase 2

Recruiting

Interventions: Device: Transcutaneous spinal cord stimulation
Other: Upper extremity rehabilitation

Brief Summary: Transcutaneous electrical stimulation (tcES) of the spinal cord has shown great promise in restoring upper extremity function after spinal cord injury (SCI). More recently, the use of invasive, epidural electrical stimulation of the spinal cord has also demonstrated promise in restoring upper extremity function post-stroke. However, the effect of stimulation parameters such as electrode configuration and stimulation frequency on excitability of the nervous system remains unknown preventing the opportunity to fully exploit this noninvasive stimulation paradigm. Additionally, the utility of noninvasive tcES in the stroke population remains unexplored. This project utilizes a comprehensive set of neurophysiological techniques, in combination with carefully chosen motor tasks, to directly link and assess the effects of stimulation parameters on neural excitability and upper extremity function during and following the delivery of cervical tcES in individuals with SCI and stroke. The fundamental knowledge gained from this project will ultimately improve the implementation of this novel and non-invasive neuromodulatory tool through an improved understanding of how tcES can facilitate recovery of function.

Detailed Description: In the first two aims of this study we explore the effects of stimulation configurations on neural excitability. Specifically we will explore the effects of electrode placement and stimulation frequency on measures of corticospinal and intracortical excitability. In the last aim of this study, individuals will participate in an interventional trial combining activity-based therapy with tcES. We will explore whether this intervention facilitated improvements in upper extremity function through clinical and neurophysiological assessments.

Recruitment & Eligibility

Inclusion Criteria

SCI cohort:

individuals aged 18 to 75 years of age who have suffered a spinal cord injury
cervical level injury (C3 to C8)
at least 1-year post-injury
for individuals taking medications for spasmolysis or muscle relaxation (e.g. oral baclofen, tizanidine, dantrolene, vigabatrin, gabapentin, or benzodiazepine), dose and regimen must be stable for at least 4 weeks prior to screening

Stroke cohort:

individuals aged 18-75 years of age who have suffered any type of stroke resulting in upper extremity motor dysfunction with partially preserved motor function
≥ 6 months post-stroke
At least 4 months since last BoNT injection for treatment of spasticity or any other condition or ≤ 2 months after study completion
for individuals taking medications for spasmolysis or muscle relaxation (e.g. oral baclofen, tizanidine, dantrolene, vigabatrin, gabapentin, or benzodiazepine), dose and regimen must be stable for at least 4 weeks prior to screening

Exclusion Criteria

Transcranial magnetic stimulation-specific exclusion criteria (both cohorts)

participants with active or inactive implants including cardiac pacemakers, implantable defibrillators, ocular implants, deep brain stimulators, vagus nerve stimulator, and implanted medication pumps
participants with conductive, ferromagnetic or other magnetic-sensitive metals implanted in their head
participants with a history of seizures or epilepsy
participants taking any medication which may reduce seizure threshold

Arm && Interventions

Group	Intervention	Description
tSCS + Rehab	Transcutaneous spinal cord stimulation	In this single arm study, individuals will receive transcutaneous spinal cord stimulation over the cervical spinal cord with upper extremity training utilizing the ReJoyce system.
tSCS + Rehab	Upper extremity rehabilitation	In this single arm study, individuals will receive transcutaneous spinal cord stimulation over the cervical spinal cord with upper extremity training utilizing the ReJoyce system.

Primary Outcome Measures

Name	Time	Method
Spinal Excitability	Baseline, End of Intervention (2mths), 6-month follow-up (8mths)	Changes in spinal excitability measured by stimulating the cervical spinal cord while recording muscle signals from upper extremity muscles will be assessed at the beginning and end of the interventional arm, and then 6 months following completion of the intervention.
Corticospinal excitability	Baseline, End of Intervention (2mths) and at 6-month follow-up timepoint (8mths)	Changes in corticospinal excitability (using transcranial magnetic stimulation) will be assessed at the beginning and end of the interventional arm, and then 6 months following completion of the intervention.
Clinical assessment of UE function	Baseline, End of Intervention (2mths), and 6-month Follow-up (8mths).	For SCI participants, the GRASSP assessment will be utilized to assess changes in upper extremity strength, sensation and function. In the stroke population, the ARAT, Fugl-Meyer tests will be utilized. In both patient groups, the arm and hand function test performed by the ReJoyce system will also be utilized.
Changes in Intracortical Excitability	Baseline, End of Intervention (2mths) and at 6-month follow-up timepoint (8mths)	Changes in intracortical excitability utilizing paired-pulse transcranial magnetic stimulation protocols will be explored at baseline, end of the intervention period, and 6months following completion of the trial.

Secondary Outcome Measures

Name	Time	Method

Locations (2): Glenrose Rehabilitation Hospital
🇨🇦
Edmonton, Alberta, Canada
University of Alberta
🇨🇦
Edmonton, Alberta, Canada