Authors: M. RATH, D. G. SAYENKO, Y. P. GERASIMENKO, V. EDGERTON
Recently we have developed the non-invasive electrical spinal stimulation technology for postural control in SCI subjects during standing. However, the potential of non-invasive spinal stimulation to facilitate trunk postural control during sitting in humans with spinal cord injury (SCI) has not been investigated. We hypothesized that transcutaneous electrical stimulation of the lumbosacral enlargement can improve trunk posture. Six participants with non-progressive SCI, C3-T9, AIS A or C, performed different motor tasks during sitting on a force platform. Electromyography of the trunk muscles, three-dimensional kinematics, and force plate data were acquired. Spinal stimulation improved trunk control during sitting in all tested individuals. Stimulation resulted in elevated activity of the erector spinae, rectus abdominis, and external obliques, contributing to trunk control, more natural anterior pelvic tilt and lordotic curve, and greater multidirectional seated stability. During spinal stimulation prior to any training, the center of pressure (COP) excursion decreased to 112.06 ± 36.00 mm from 143.74 ± 30.79 mm (p=.028, Z=-2.2014) without stimulation and to 93.09 ± 37.42 mm from 123.77 ± 48.44 mm (p=.028, Z=-2.2014) without stimulation in quiet sitting before training and after training respectively. Similarly, the limits of stable displacement increased by 31.40 ± 37.28% (p=.046, Z=1.9917), 19.42 ± 15.83% (p=.046, Z=1.9917), 54.11 ± 54.36% (p=.028, Z=2.2014), and 49.69 ± 32.343% (p=.046, Z=1.9917) before training and 24.06 ± 16.06% (p=.028, Z=2.2014), 20.25 ± 22.01% (p=.075, Z= 1.7821), 27.87 ± 11.88% (p=.028, Z=2.2014), and 27.33 ± 44.42% (p=.116, Z= 1.5724) after training in the forward, backward, right, and left directions, respectively. These data demonstrate that the spinal networks can be modulated transcutaneously with tonic electrical spinal stimulation to physiological states sufficient to generate a more stable, erect sitting posture after chronic paralysis.
Grant Support: Paralyzed Veterans of America (PVA) Research Foundation Grant #3068, NIH SBIR Grant R43EB018232, Russian Foundation for Fundamental Research Grant 16-29-08173-ofi-m
M. Rath: None. D.G. Sayenko: None. Y.P. Gerasimenko: E. Ownership Interest (stock, stock options, royalty, receipt of intellectual property rights/patent holder, excluding diversified mutual funds); shareholder interest in NeuroRecovery Technologies. V. Edgerton: E. Ownership Interest (stock, stock options, royalty, receipt of intellectual property rights/patent holder, excluding diversified mutual funds); shareholder interest in NeuroRecovery Technologies.
*M. RATH1, D. G. SAYENKO1, Y. P. GERASIMENKO2, V. EDGERTON3;
1UCLA, Los Angeles, CA; 2Pavlov Inst. of Physiol, St Petersburg, Russian Federation; 3Dept Integrative Biol. & Physiol., Univ. of California Los Angeles, Los Angeles, CA. Regaining trunk stability after spinal cord injury. Program No. 138.16. 2018 Neuroscience Meeting Planner. San Diego, CA: Society for Neuroscience, 2018. Online.