Optimizing Transcutaneous Spinal Cord Stimulation: An Exploratory Study on the Role of Electrode Montages and...

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Biomedical Engineering

Background:

• Transcutaneous spinal cord stimulation (tSCS) offers a non-invasive approach to enhance motor function post-spinal cord injury (SCI) by modulating spinal reflex pathways.
• Optimizing tSCS requires understanding how electrode montages and targeted spinal levels influence neurophysiological responses.

Purpose of the Study:

• To investigate the impact of different tSCS electrode placements and spinal targets on neurophysiological outcomes.
• To compare responses in individuals with SCI and healthy controls to inform personalized tSCS strategies for motor recovery.

Main Methods:

• Utilized single- and paired-pulse tSCS paradigms in five participants (3 SCI, 2 controls).
• Varied electrode montages and targeted spinal levels.
• Analyzed electromyographic responses, including spinally evoked motor responses (sEMRs) and paired-pulse modulation.

Main Results:

• Electrode configuration and spinal level significantly affected sEMR threshold and incidence across all participants.
• Individuals with SCI exhibited greater second-pulse attenuation (48%) compared to controls (12%, p=0.0425) in paired-pulse tests.
• Distinct trends in responses were observed based on montage and muscle group.

Conclusions:

• Spinal level, electrode configuration, and paired-pulse effects are critical for tailoring tSCS interventions.
• Findings support the development of patient-centered tSCS strategies for SCI rehabilitation.
• Further validation in larger, diverse cohorts is recommended.