Using Non-invasive Brain and Spinal Cord Stimulation to Improve Arm and Hand Function After Spinal Cord Injury

Summary

Cervical spinal cord injury (SCI) disrupts communication between the brain and spinal circuits, affecting voluntary movement control and contributing to arm and hand impairments, the top recovery priority for people with tetraplegia. Although rehabilitation and emerging neuromodulation approaches can support meaningful gains, many individuals experience persistent limitations in reaching and grasping. Current noninvasive stimulation strategies typically target the brain OR the spinal cord alone, despite strong reciprocal interactions between these structures. Cervical transcutaneous spinal cord stimulation (tSCS) can enhance upper limb function. Cerebellar stimulation, given its key role in sensorimotor integration and modulation of corticospinal excitability, represents a promising but underexplored therapeutic target. Theta burst stimulation (TBS), a rapid form of repetitive transcranial magnetic stimulation (TMS), induces lasting changes in cortical excitability and may promote associative plasticity when paired with spinal cord stimulation. This double-blind, randomized, sham-controlled pilot trial (n=24) will evaluate the feasibility, preliminary efficacy, and mechanisms of combined cerebellar TBS + cervical tSCS in people with chronic cervical SCI (AIS B, C or D). Participants will either receive cerebellar TBS + cervical tSCS, tSCS only, or sham stimulation while engaging in functional task practice such as pinching and grasping 3x/week for 8 weeks. Feasibility outcomes include adherence, retention, and safety. Efficacy will be assessed using the GRASSP strength sub-score and KINARM-based measures of sensorimotor control. Mechanistic outcomes will assess changes in cortical and spinal cord functional connectivity using resting state fMRI, corticospinal excitability using motor evoked potentials, and spinal excitability using the H reflex. Findings will establish whether combined cerebellar TBS and cervical tSCS is feasible, safe, and capable of enhancing upper limb recovery.

Conditions

• Spinal Cord Injuries and Disorders (SCI/D)

Interventions

DEVICE

Cerebellar theta burst stimulation

Theta burst stimulation (TBS) is a pattern of repetitive transcranial magnetic stimulation that will be delivered over the lateral hemisphere of the cerebellum. Sham TBS will be delivered using a sham coil over the cerebellum.

DEVICE

Cervical transcutaneous spinal cord stimulation

Non-invasive electrical stimulation at 30Hz will be delivered through 2 round electrodes placed over the cervical vertebrae to target the cervical spinal cord. Sham cervical tSCS will involve briefly increasing stimulation intensity to the sensory threshold, followed by reducing the intensity to zero for the remainder of the session

BEHAVIORAL

Functional task practice

All participants will complete 60-minute sessions of functional task practice three times per week for eight weeks, delivered concurrently with either real or sham stimulation. Following functional task practice guidelines, training will consist of repetitive, goal-directed upper-limb activities designed to promote functional independence in everyday tasks.

Sponsors & Collaborators

• University of British Columbia

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Model

PARALLEL

Eligibility

Min Age

19 Years

Max Age

75 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-03-01

Primary Completion

2030-11-01

Completion

2031-02-28

Countries

• Canada

Study Locations