12:01am

Fri May 20, 2011
Health

Spinal Implant Spurs Motion In Paralyzed Man

Rob Summers was a 20-year-old college baseball pitcher when a hit-and-run driver ran him down, paralyzing him from the chest down. But that was five years ago. Summers can now move his legs, feet and toes, and he can even stand up.

That's because of an experimental treatment that combines intensive physical therapy with electrical stimulation of the spinal cord.

"To everyone's disbelief, I was able to stand independently, the third day we turned it on," Summers said.

That may sound just like flipping a switch, but it was hardly that easy.

Summers spent more than two years before that doing what they call locomotor training: daily sessions on a treadmill, supported by a harness while therapists moved his legs.

Then, in 2009, surgeons put electrodes in his lower back, delivering a tiny bit of electricity to his spine.

"The stimulator feels like a tingling, and depending on the voltage it's either a weaker tingling that starts in my abs and goes down to my toes, or as the voltage gets higher it gets more intense," he said.

With the stimulator turned on, therapists helped Summers practice standing and moving his legs. He can now do that on his own. The study was published online in The Lancet.

Reggie Edgerton, one of the researchers, was working on this therapy for years, but seeing Summers move his legs was a big surprise.

"None of us believed that," he said. "I was afraid to believe it when I first saw it."

The researchers think that it's the electrical stimulation that made the difference.

"This demonstrates a concept, and it's a new concept," Edgerton said. "This demonstrates that you can regain voluntary control, but the voluntary control is only regained in the presence of stimulation."

Nerves talk to each other with electrical impulses, so it's not surprising that electricity was somehow involved. It could be that it amplified signals that the nerves were too weak to pick up on their own — kind of like using a hearing aid to boost sounds. Or it could be that the exercise helped — there's lots of evidence that intensive exercise can spark the growth of new nerve cells.

But the scientists say they really don't know why this worked — and they've got much more work to do to figure it out.

Lex Frieden, a professor of rehabilitation at the University of Texas Health Science Center in Houston, was paralyzed in a car crash in 1967.

"Those of us who have spinal-cord injuries who are looking for a cure tomorrow are simply going to have to wait," Frieden said.

Even for Summers, his new ability to move has not become part of normal life. For one thing, he can move only when the electricity's turned on.

"I turn the stimulator on for two hours a day, I try to do one hour of standing, independently by myself, as well I do one hour of voluntary movement, with the stimulator on, moving hips, ankles, knees, just as if I was in the gym," Summers said.

But he's hardly complaining.

"I had a shot in my lower back just the other day as part of a checkup and I felt the entire thing — the needle go in, the pain, everything," he said. "So that was both good and bad, exciting to experience that again, but knowing that I continue to make progress is very exciting."

Summers says he's happy with this progress, but researchers caution that they've only seen results in this in one patient, and it is far from a cure. Copyright 2011 National Public Radio. To see more, visit http://www.npr.org/.