LOS ANGELES — A 25-year-old Los Angeles man paralyzed from the waist down after being hit by a car in 2006 has regained the ability to stand, take steps on a treadmill and move his hips, knees, ankles and toes voluntarily as a result of an experimental treatment developed at the University of California-Los Angeles and the University of Louisville in Kentucky.
Rob Summers also has regained some bladder and sexual function after intensive rehabilitation and two years of electrical stimulation to his damaged spinal cord with a device normally used for pain relief, researchers reported Thursday.
His recovery “remains unprecedented in spinal-cord-injury patients,” who, until now, have faced a lifetime of paralysis, researchers from the University of Zurich wrote in an editorial accompanying the report in the journal Lancet. “We are entering a new era when the time has come for spinal-cord-injured patients to move.”
The new treatment is “a very exciting discovery” that can probably be used to help 10 percent to 15 percent of people with spinal-cord injuries regain some use of their legs, added Dr. John McDonald, director of the International Center for Spinal Cord Injury at the Kennedy Krieger Institute in Baltimore, who was not involved in the research.
To achieve this milestone, researchers bathed Summers’ spinal cord with a mild dose of electricity using an implanted device that is normally used to treat chronic pain. The electrical stimulation apparently primed his nervous system to respond to signals from his limbs, allowing him to rise out of his wheelchair.
“To everyone’s disbelief, I was able to stand independently the third day we turned it on,” said Summers, who was a baseball player in his junior year at Oregon State University at the time of the hit-and-run accident.
The treatment, devised primarily by UCLA neurobiologist V. Reggie Edgerton, is designed to activate a patient’s spinal nerves just enough to make them responsive to sensory signals coming from the legs, like using a hearing aid to amplify sound.
According to the Christopher and Dana Reeve Foundation, almost 6 million people live with some form of paralysis, about 1.3 million of them from a spinal-cord injury.
Researchers have previously used electrical pulses to activate nerves in the legs of spinal-cord patients in a specific pattern that caused them to stand or move in a walking motion. But in those cases, the computer that sends the pulses has control of the activity, not the patient’s brain.
The important thing, Edgerton noted, is that the device did not cause Summers to stand. When Summers is sitting normally with the stimulus operating, nothing happens. But when he leans forward and puts some weight on his legs, muscle memory takes over, and the spine sends signals to the legs that cause him to stand.
With more training, Summers also learned how to walk on a treadmill. Eventually, he developed the ability to move his legs, wiggle his toes, flex his ankles and make other movements voluntarily, as long as his spinal cord is stimulated.
At first, “none of us believed it,” Edgerton said. “We have no idea what the mechanisms are, but we are pretty sure it has resulted in changes in the brain.”
And as Summers relearned these rudimentary activities, his autonomic functions also improved. He regained control of his bladder and bowels, as well as some sexual function.
“Not being able to walk and stand is devastating,” said Dr. Susan Harkema of the University of Louisville, the study’s co-author, “but these other things may be more important.”
