In a study conducted at UCLA, five men who had been completely paralyzed were able to voluntarily move their legs in a rhythmic motion thanks to a new noninvasive (neuromodulation) procedure that stimulates the spinal cord.
The researchers believe this to be the first time that voluntary leg movements have ever been relearned in completely paralyzed patients without surgery. The results are reported in an open-access paper, the Journal of Neurotrauma.
“These findings tell us we have to look at spinal cord injury in a new way,” explains V. Reggie Edgerton, senior author of the research and a UCLA distinguished professor of integrative biology and physiology, neurobiology and neurosurgery.
Edgerton said although it will likely be years before the new approaches are widely available, he now believes that it is possible to significantly improve the quality of life for patients with severe spinal cord injuries and to help them recover multiple body functions.
Five men were given one 45-minute training session per week for 18 weeks. For four of the weeks, five of the men were also given twice daily doses of buspirone, a drug often used to treat anxiety disorders, as a part of the treatment.
Researchers placed electrodes at strategic points on the skin, at the lower back and near the tailbone and then administered a unique pattern of noninvasive and painless transcutaneous (through the skin) electrical currents. The electrical charges caused no discomfort to the patients.
“The fact that they regained voluntary control so quickly must mean that they had neural connections that were dormant, which we reawakened,” said Edgerton, who for nearly 40 years has conducted research on how the neural networks in the spinal cord regain control of standing, stepping and voluntary control of movements after paralysis. “It was remarkable.”
Edgerton said most experts, including himself, had assumed that people who were completely paralyzed would no longer have had neural connections across the area of the spinal cord injury.
The researchers do not know yet whether patients who are completely paralyzed can be trained to fully bear their weight and walk.
“Many people thought just a few years ago we might be able to achieve these results in perhaps one out of 100 subjects, but now we have nine of nine,” Edgerton said. “I think it’s a big deal, and when the subjects see their legs moving for the first time after paralysis, they say it’s a big deal.”
“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,” said Dr Roderic Pettigrew, director of the National Institute of Biomedical Imaging and Bioengineering. “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. It’s a wonderful example of the power that comes from combining advances in basic biological research with technological innovation.”
Edgerton estimates that the cost of the new approach could be 1/10 the cost of treatment using the surgical epidural stimulator (which is still experimental), and because it doesn’t require surgery, it would likely be more easily available to more patients.
Edgerton and his research team also plan to study people who have severe, but not complete, paralysis. “They’re likely to improve even more,” he said.
The scientists can only work on a small number of patients due to limited resources, but Edgerton is optimistic that the research can benefit many others. Nearly 1 in 50 people are living with paralysis, almost 6 million Americans live with paralysis, including 1.3 million with spinal cord injuries.