A new strategy that uses non-invasive spinal cord stimulation has allowed five men with motor paralysis to move their legs, according to study results recently published in the Journal of Neurotrauma.
The study, funded by the NIH, uses a strategy called transcutaneous stimulation, which delivers electrical current to the spinal cord through the use of electrodes placed on the skin of the lower back.
The patients were able to move their legs while suspended in braces that hung from the ceiling. The movements were not comparable to walking, as the braces prevented resistance from gravity; however, researchers reported the results showed significant progress toward the development of therapy for people with spinal cord injury.
“These encouraging results provide continued evidence that spinal cord injury may no longer mean a lifelong sentence of paralysis and support the need for more research,” Roderic Pettigrew, PhD, MD, director of the National Institute of Biomedical Imaging and Bioengineering at the NIH, said in a press release. “The potential to offer a life-changing therapy to patients without requiring surgery would be a major advance; it could greatly expand the number of individuals who might benefit from spinal stimulation.”
The team of researchers who conducted the study was led by V. Reggie Edgerton, PhD, distinguished professor of integrative biology and physiology at UCLA, and Yury Gerasimenko, PhD, director of the Laboratory of Movement Physiology at the Pavlov Institute and a researcher in UCLA’s Department of Integrative Biology and Physiology.
The five patients, each of whom had been paralyzed for more than 2 years, underwent weekly 45-minute sessions for 18 weeks to determine the effects of non-invasive electrical stimulation on their ability to move their legs. Sessions included stimulation as well as several minutes of conditioning, during which their legs were moved for them manually in a step-like pattern. The patients were instructed to try to move their legs or to remain passive at different points throughout each session while receiving stimulation.
Throughout the final 4 weeks of the study, the patients took the pharmacological drug, buspirone.
After 4 weeks of spinal stimulation and physical training, the patients were able to double their range of movement when voluntarily moving their legs while receiving stimulation. After the addition of buspirone, the patients moved their legs with no stimulation and were able to maintain the range of movement they had reached with stimulation, according to the release.
“It is as if we have reawakened some networks so that once the individuals learned how to use those networks, they become less dependent and even independent of the stimulation,” Edgerton said in the release.
In a prior study, Edgerton and colleagues reported patients with motor paralysis were able to generate some voluntary movements while receiving electrical stimulation to their spinal cords from a surgically implanted device. The researchers then began developing a strategy to deliver non-invasive stimulation to the spinal cord to expand the number of patients that could benefit from spinal cord stimulation.
“There are a lot of individuals with spinal cord injury that have already gone through many surgeries, and some of them might not be up to or capable of going through another,” Edgerton said. “The other potentially high impact is that this intervention could be close to one-tenth the cost of an implanted stimulator.”
Edgerton is continuing studies on the patients who received non-invasive stimulation to determine whether it can restore patients’ ability to bear weight and regain autonomic functions lost due to paralysis. He also hopes to test non-invasive stimulation on patients with partial paralysis. Further development of non-invasive stimulators could allow for additional benefits, Edgerton said.
Reference: Edgerton, et al. J Neurotrauma. 2014;doi:10.1089/neu.2015.4008
Disclosure: The researchers report the study was supported in part by the National Institute of Biomedical Imaging and Bioengineering, the National Institute of Neurological Disorders and Stroke, the Eunice Kennedy Shriver National Institute of Child Health and Human Development, and the National Center for Advancing Translational Sciences at NIH under award numbers EB015521, EB007615, and TR000124, the Christopher and Dana Reeve Foundation, the Walkabout Foundation, the F. M. Kirby Foundation, the Russian Foundation for Basic Research grant 13-04-12030, the Russian Scientific Fund project 14-45-00024, the J. Yang and Family Foundation, and the Paul and Daisy Soros New American Fellowship.
