The Food and Drug Administration (FDA) gave the research team approval to test five spinal-cord injury patients; the next patient will be matched with the first, in terms of age, injury, and physical ability, to see if the findings can be replicated. In subsequent trials, patients who have no sensation will be implanted with the device, to see if this influences the outcome.
"This is a significant breakthrough," says Susan Harkema of University of Louisville, the lead author of the paper in The Lancet. "It opens up a huge potential to improve the daily functioning of individuals."
"While these results are obviously encouraging, we need to be cautious, and there is much work to be done," says Edgerton.
One of the biggest obstacles is that the electrode array implanted in the human patient is FDA-approved for back pain only. The use of the FDA-approved device was meant "as a test to see if our concepts would work, providing us with additional ammunition to motivate the development of the arrays used in animal studies," says Burdick. The current FDA-approved arrays, he adds, have many limitations, "hence, the further development of the arrays that have currently only been tested in animals should provide even better human results in the future."
Using a combination of experimentation, computational models of the array and spinal cord, and machine-learning algorithms, Burdick and his colleagues are now trying to optimize the stimulation pattern to achieve the best effects, and to improve the design of the electrode array. Further advances in the technology should lead to better control of the stepping and standing processes.
In addition, he says, "our team is looking at other ways to apply the technology. We may move the array up higher on the spinal column to see if it could affect arms and hands, as well as the legs."
|Contact: Deborah Williams-Hedges|
California Institute of Technology