# Transspinal versus Epidural Stimulation for Exoskeletal Assisted Walking after Spinal Cord Injury

> **NIH VA I21** · VA VETERANS ADMINISTRATION HOSPITAL · 2020 · —

## Abstract

Restoring locomotion following spinal cord injury (SCI) has been the focus of years of research aimed at
ameliorating several of health-related comorbidities. Spinal cord epidural stimulation (SCES) exhibits the
rehabilitation potential of restoring locomotion in individuals with SCI when combined with intensive locomotion
training. Despite this potential, such protocols are likely impractical when applied across large clinical SCI
populations due to high monetary costs. Similar to SCES, transspinal stimulation (TS) has also exhibited
neuromodulatory benefits by externally stimulating lumbro-sacral neural circuity to generate step-like activities
in persons with complete SCI; however, these techniques also require intense gait training. Recently robotic
exoskeletons have been used as a promising tool to circumvent limitations associated with labor-intensive
locomotor training, and have been safely used as an effective approach in improving levels of physical activity
in persons with complete SCI.
Recent work has demonstrated the benefits of combining EAW and neuromodulatory techniques. Following
12-weeks of EAW+SCES training, improvements in locomotion led researchers to decrease the amount of
EAW swing assistance to 35% in a person with a C7 complete SCI. This was accompanied by 573 unassisted
steps, which represents 50% of the total number of steps taken during that session. Electromyographic (EMG)
activity also increased during both stance and swing phases, reflecting the individual’s ability to rhythmically
fire paralyzed muscles during EAW+SCES. Additionally, cardio-metabolic loads were increased during
exoskeletal stepping when combined with SCES as compared to stepping without SCES. The participant also
showed a modest decrease in his total and regional absolute fat mass. These preliminary findings suggest that
neuromodulation using SCES with exoskeletal ambulation may provide a feasible rehabilitation approach for
persons with SCI. The goal of the current study is to examine and compare the effects of EAW combined
with SCES or TS in persons with motor complete SCI. The data generated from this application will also enable
larger clinal trials to explore ways to optimize exoskeletal assisted gait training through the use of different
neuromodulation modalities with SCI.
Following a repeated-measure design, 10 participants with chronic, motor complete (AIS A and B) SCI
(age:18-60 years) will be randomly assigned to participate in either 6-months of EAW+SCES (n=5) or
EAW+TS (n=5) training. The entire duration of the trial will be approximately 1 year for each participant.
Initially, participants will undergo 3-months of EAW training (3 sessions/week), which will be followed by
randomization into either a EAW+SCES group or EAW+TS group for an additional 6-months of training (both
groups: 3 sessions/week) and a 3-month follow-up period for both groups. Measurements at baseline (BL:
prior to EAW) and 4 post-intervention timepoints will occur ev...

## Key facts

- **NIH application ID:** 10012247
- **Project number:** 1I21RX003456-01
- **Recipient organization:** VA VETERANS ADMINISTRATION HOSPITAL
- **Principal Investigator:** Ashraf S Gorgey
- **Activity code:** I21 (R01, R21, SBIR, etc.)
- **Funding institute:** VA
- **Fiscal year:** 2020
- **Award amount:** —
- **Award type:** 1
- **Project period:** 2020-07-01 → 2022-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10012247

## Citation

> US National Institutes of Health, RePORTER application 10012247, Transspinal versus Epidural Stimulation for Exoskeletal Assisted Walking after Spinal Cord Injury (1I21RX003456-01). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10012247. Licensed CC0.

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