Spine Implant Lets Paralyzed People Walk Again

Lausanne, Switzerland —(Map)

When someone damages their backbone, the injury can leave them paralyzed and unable to walk. Now, scientists have given three paralyzed men the ability to walk again, thanks to a device placed in their spine. Incredibly, the men were able to walk in just hours.

The human backbone, or spine, doesn’t just help us stand up straight. Inside the spine is the spinal cord, which carries important information between the head and the lower part of the body. This information moves around as tiny, short bursts of electricity which travel between the brain and the other parts of the body.

The legs and feet send “sense” information to the brain, saying they’re hurt or hot, for example. And the brain sends signals to the lower body, perhaps telling the legs to walk, dance, or sit down. Toward the bottom of the backbone, bundles of nerves leave the spine. Different bundles help control different groups of muscles in the legs.

When someone’s spinal cord is hurt, this important pathway can get damaged. That can mean that information about senses doesn’t reach the brain from the lower body, and that control signals can’t make it to the lower body from the brain. When that happens, a person is “paralyzed”, and they can’t move their legs.

Now scientists in Lausanne, Switzerland have given three paralyzed men the ability to walk again. Each of the three men had damaged their spinal cords in motorcycle accidents and couldn’t move their legs.

To help them walk again, the men had surgery. A special device was placed directly on the lower part of their spinal cord, below their injury. This “implant” contained sixteen electrodes. Electrodes are small objects that electricity can pass through. The researchers made sure the electrodes on the implant were lined up with the bundles of nerves that control the leg muscles.

To begin with, the scientists controlled the implants from a tablet computer. Just hours after the implants were first used, all three men were taking steps, with support.

In the past, scientists have had some success with similar implants in the lower spine. Some patients have even trained themselves over months to be able to walk.

This research is different. The patient’s brains aren’t sending “walking” messages to their legs. Instead, the tablet tells the implant to send the walking messages (as a set of electrical signals).

The researchers used computers to generate patterns of movement – like taking a step – that would work well with each patient. The patient then uses the tablet to choose the pattern they want. That triggers the implant, and the muscles move in the chosen way.

Over time, the men were able to walk entirely on their own, using a special walker with buttons to trigger each leg. One of the men has walked for half a kilometer (0.31 miles) on his own with the walker.

The solution isn’t perfect. It’s very expensive, it requires difficult surgery, and the patients can’t walk without the system. But the scientists are hopeful that in the future, this sort of technology will allow many paralyzed people to begin to walk again in just hours.

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Did You Know…?
It’s not just walking. The researchers also created patterns of movement that allowed the men to do other activities, including pedaling a recumbent (sitting) bicycle.