By Mark Aragona
Forget about exoskeletons—a specially-designed electric device just may do the trick.
Rob Summers, a 25-year old native of Portland, Oregon, was the victim of a hit-and-run in 2006. While he survived, Summers was paralyzed from the chest down—crushing news for the former baseball player. After undergoing three years of intensive physical therapy with no significant improvement, there seemed little hope that Summers would ever walk again.
In 2009, doctors implanted an electrode array into the lining of Summers’s lower spine in hopes of stimulating his dormant nerve connections. Days later, Summers could stand up on his own. He surprised doctors by being able to move his hips, legs, and toes upon command. After weeks of training and with the aid of a harness, he got on a treadmill and walked into medical history.
While there have been cases where electric stimulation helped some patients with spinal cord injuries, it was never as fast or as extensive as Summers’s case. “The moment I stood up I was in disbelief,” he says. “I was amazed, I was shocked. The doctors had anticipated in maybe five years I could stand, and standing on the third day, I blew all the doctors out of the water.”
How the spinal electrode device helps Summers regain control of his limbs is not yet fully understood. The implant, a product of Medtronic, Inc., is normally used to relieve chronic lower back pain by pulsing electric signals that mimic those sent between the human brain and the lower limbs. Doctors believe that this stimulation “wakes up” the injured nerves in Summers’s lower back, thereby allowing his brain and limbs to communicate with each other again.
There are still some limitations to this technology: Summers cannot control his legs when the device is off and doctors have limited its use to only a few hours each day. It is also important to note that Summers still retained some sensation in his legs after his accident, meaning the nerve connections were not totally severed.
Researchers agree that while the device itself does cannot cure paralysis, it could lead to greater functionality for patients with similar injuries. Current plans are to test the device on four more patients as well as create a new design specifically to help paralytics. They are also looking into drugs to further improve the communication process in spinal injuries.
The project was a joint effort of the University of California, Los Angeles (UCLA), the California Institute of Technology (Caltech), and the University of Louisville with funding from the US National Institutes of Health and the Christopher and Dana Reeve Foundation.