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Spinal cord epidural stimulation can neuromodulate the human spinal circuitry controlling posture and locomotion, which remains most often intact below the level of injury, by primarily recruiting dorsal root fibers carrying somatosensory information.
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Spinal cord epidural stimulation, sensory feedback, and clinically undetected, residual volitional descending input can synergistically contribute to motor function recovery after chronic, motor complete spinal cord injury.
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The selection of spinal
Physical Medicine and Rehabilitation Clinics of North America
Spinal Cord Epidural Stimulation for Lower Limb Motor Function Recovery in Individuals with Motor Complete Spinal Cord Injury
Section snippets
Key points
Spinal cord characteristics underlying spinal stimulation- and training-induced motor recovery after spinal cord injury
Spinal cord stimulation and activity-based training aim at capitalizing on the human spinal cord sensory-motor potential that still persists after chronic, clinically complete SCI. In particular, (i) automaticity, (ii) residual supraspinal connections to the spinal circuitry, and (iii) plasticity are briefly discussed in this section.
Spinal cord epidural stimulation, sensory feedback, and residual volitional descending input: synergic contribution for motor function recovery after spinal cord injury
Decades of work on animal models with complete SCI initially suggested to apply scES with the goal of modulating the excitability of spinal circuitry, mimicking the tonic supraspinal drive lost after SCI, so that sensory information from lower limbs could serve as a source of control for generating appropriate motor patterns during standing and stepping.9 In addition, the serendipitous findings related to the reenabling of volitional lower limb movements using scES led to further efforts aimed
Future directions
Future studies with a larger number of SCI individuals and broader range of age and time since injury, among others, are needed to better understand the mechanisms underlying motor recovery after severe SCI using scES, as well as its potential for translation to the home and community environment. Similarly, it will be important to identify neurophysiological and imaging markers that may predict which individuals are more likely to benefit from this intervention. Technological advancements are
Acknowledgments
The authors thank Dr Susan Harkema for her helpful feedback on the article. The authors are supported by The Leona M. and Harry B. Helmsley Charitable Trust, Craig H. Neilsen Foundation, and Christopher & Dana Reeve Foundation.
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Disclosure Statement: The authors have nothing to disclose.