Spinal-cord stimulation allows you to walk with assistance

"It's an amazing feeling," says David Mzee, whose left leg was paralyzed in 2010. Mzee has made some breakthrough in spinal-cord stimulation technology. "I can do a knee extension of my left leg … flex my hip and even move my toes."

Mzee is one of three participants in a study that used a new technique to overcome spinal cord injury and restore walking ability in patients with varying degrees of paralysis. The results, published in Nature and Nature Neuroscience today, are dramatic. All three patients were recognized for their mobility and their progress in physical-therapy.

The basis of the technique, called epidural electrical stimulation (EES), is not new at all-it's been investigated as a potential treatment for paralysis for decades, with a lot of success in animals. And in September this year, two separate papers have been reported with patients with paralysis to walk, with assistance, as a result of EES.

But the sooner patients made progress after the months of intensive rehabilitation in the future, closer to a year. What Grégoire Courtine, Jocelyne Bloch, and a large team of researchers report today is a huge leap forward: their patients were able to walk with others.

Blocking the feedback loop

The difference lies in how constant the electrical stimulation is. EES works by implanting a device that delivers electrical signals to the spinal cord. Bridging the gap between the spinal cord and the spinal cord and the spinal cord, EES can help to bridge the gap by providing electrical signals to the spinal cord below the injury site.

In rodents, cats, and even monkeys, EES has allowed "standing, walking in various directions, and even running," write Courtine and his colleagues. They suggest that this technique has been successful in humans because of the continuous stimulation of brain stimulation, and effectively blocking the brain's sense of being in space. Physiological differences between humans and rats-including the difference in body size-could explain why these humans and not rats, they suggest.

The systems needed to get more precise. And so the researchers set up an understanding of the nervous system. Then they would have worked out where exactly the electrodes would be provided to provide feedback to those systems that would be needed.

Patients in the study of the three patients in the study, adapting to the individual measurements of each person's spinal cord. They are a well-known member of the medical team, who conducts fluid therapy, allowing the team to work out where they are. Then the pattern of electrical signals was calibrated for each individual.

"All the patients could walk within one week," says Blotch. In ongoing tests of the system, the patients were able to adjust their length and distance of travel. All movement was under voluntary control; EES does not generate movement on its own.

"The participants are constantly challenged to voluntarily generate the appropriate leg movements," says co-author Karen Minassian. "They need to be mentally active all the time in order to close the loop with the electrical stimulation that produces muscle activity."

Re-establishing connections

Because of that commitment, the treatment as well as the recovery was restored. Mzee, whose left leg had been completely paralyzed after a gymnastics accident, had undergone extensive rehabilitation treatment, but with little progress. After five months, he was able to take a few steps on his own, completely unassisted. With EES switched on, he's able to walk using a walker.

Gert-Jan Oskam, who lost the use of both sides in a cycling accident, had also made very limited progress in rehabilitation before the study. "Now I can walk short distances with the help of electrical stimulation and even without electrical stimulation," he says. While he can take a few steps with crutches or stand up with another person for support, "I should be able to have a BBQ standing on my own in the near future."

Even within the group of three patients, the results have been markedly different. For Sebastian Tobler, the five months have not been long enough to restore much voluntary movement without EES. But he is able to lift his legacy while lying down without EES, and he says that he is better in life. He plans to continue training.

The degree of success for the treatment of stroke is one of a number of factors, including the severity of the injury and the degree of residual movement. For some, like Mzee, it could result in a dramatic improvement for others, this might not be the case. Understanding the results in a larger population is a crucial next step.

For Courtine, Bloch, and their colleagues, the next step is to explore results in people with recent injuries, where "the potential for plasticity is elevated and the neuromuscular system has not yet undergone the atrophy that follows chronic paralysis," they write. While they are in the process of continuing their studies, they would have limited success in humans, which would be more likely to be more likely to be successful. rolled out across the board.

And essential, they add, is ensuring that the treatment translates outside of the hospital. The researchers developed a voice-activated system that allowed them to switch to EES on and off themselves, and they calibrated it to different modes for walking, standing, or cycling on a hand-and-leg-powered tricycle. Getting EES working is one thing, but they also have an eye on making it possible for patients to use home-supporting "rehabilitation in clinical settings and use in the community."

Nature, 2018. DOI: 10.1038 / s41586-018-0649-2 (About DOIs).