Transcutaneous spinal cord stimulation improves postural stability in individuals with multiple sclerosis

Brad W R Roberts; Darryn A Atkinson; Gerome A Manson; Rachel Markley; Teresa Kaldis; Gavin W Britz; Philip J Horner; Albert H Vette; Dimitry G Sayenko

doi:10.1016/j.msard.2021.103009

Transcutaneous spinal cord stimulation improves postural stability in individuals with multiple sclerosis

Mult Scler Relat Disord. 2021 Jul:52:103009. doi: 10.1016/j.msard.2021.103009. Epub 2021 May 7.

Authors

Brad W R Roberts¹, Darryn A Atkinson², Gerome A Manson³, Rachel Markley⁴, Teresa Kaldis⁵, Gavin W Britz⁶, Philip J Horner⁷, Albert H Vette⁸, Dimitry G Sayenko⁹

Affiliations

¹ Department of Mechanical Engineering, University of Alberta, 9211 116 Street NW, Edmonton, Alberta, T6G 1H9, Canada. Electronic address: bwr@ualberta.ca.
² College of Rehabilitative Sciences, University of St. Augustine for Health Sciences, 5401 La Crosse Avenue, Austin, TX, 78739, United States. Electronic address: datkinson@usa.edu.
³ Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, 6550 Fannin Street, Houston, TX, 77030, United States. Electronic address: gm99@queensu.ca.
⁴ Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, 6550 Fannin Street, Houston, TX, 77030, United States. Electronic address: rmarkley@houstonmethodist.org.
⁵ Department of Physical Medicine and Rehabilitation, Center for Neuroregeneration, Houston Methodist Research Institute, 6560 Fannin Street, Houston, TX, 77030, United States. Electronic address: tkaldis@houstonmethodist.org.
⁶ Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, 6550 Fannin Street, Houston, TX, 77030, United States. Electronic address: gbritz@houstonmethodist.org.
⁷ Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, 6550 Fannin Street, Houston, TX, 77030, United States. Electronic address: pjhorner@houstonmethodist.org.
⁸ Department of Mechanical Engineering, University of Alberta, 9211 116 Street NW, Edmonton, Alberta, T6G 1H9, Canada; Glenrose Rehabilitation Hospital, Alberta Health Services, 10230 111 Avenue NW, Edmonton, Alberta, T5G 0B7, Canada; Neuroscience and Mental Health Institute, University of Alberta, 87 Avenue & 112 Street, Edmonton, Alberta, T6G 2E1, Canada. Electronic address: albert.vette@ualberta.ca.
⁹ Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, 6550 Fannin Street, Houston, TX, 77030, United States. Electronic address: dgsayenko@houstonmethodist.org.

PMID: 34023772
DOI: 10.1016/j.msard.2021.103009

Abstract

Background: Widespread demyelination in the central nervous system can lead to progressive sensorimotor impairments following multiple sclerosis, with compromised postural stability during standing being a common consequence. As such, clinical strategies are needed to improve postural stability following multiple sclerosis. The objective of this study was therefore to investigate the effect of non-invasive transcutaneous spinal stimulation on postural stability during upright standing in individuals with multiple sclerosis.

Methods: Center of pressure displacement and electromyograms from the soleus and tibialis anterior were recorded in seven individuals with multiple sclerosis during standing without and with transcutaneous spinal stimulation. Center of pressure and muscle activity measures were calculated and compared between no stimulation and transcutaneous spinal stimulation conditions. The relationship between the center of pressure displacement and electromyograms was quantified using cross-correlation analysis.

Results: For transcutaneous spinal stimulation, postural stability was significantly improved during standing with eyes closed: the time- and frequency-domain measures obtained from the anterior-posterior center of pressure fluctuation decreased and increased, respectively, and the tibialis anterior activity was lower compared to no stimulation. Conversely, no differences were found between no stimulation and transcutaneous spinal stimulation when standing with eyes open.

Conclusion: Following multiple sclerosis, transcutaneous spinal stimulation improved postural stability during standing with eyes closed, presumably by catalyzing proprioceptive function. Future work should confirm underlying mechanisms and explore the clinical value of transcutaneous spinal stimulation for individuals with multiple sclerosis.

Keywords: Center of pressure; Electromyogram; Multiple sclerosis; Neuromodulation; Transcutaneous electrical spinal cord stimulation; Trunk stability and control.

MeSH terms

Electromyography
Humans
Multiple Sclerosis*
Muscle, Skeletal
Postural Balance
Spinal Cord
Spinal Cord Stimulation*
Standing Position