New High-Tech Bionic Arm Helps Wounded Warrior
(CHICAGO) — Glen Lehman’s battles in Iraq came to an end when a grenade tore through the door of his Humvee, shredding his right arm. Lehman survived, thanks to his quick-thinking comrades and a helicopter evacuation to a nearby air base for emergency medical care. But a new battle was just beginning for the sergeant first class and father of two, who fought excruciating phantom limb pain where his arm used to be.
On top of the pain, Lehman struggled to control his prosthetic arm, which ended with a pincer in place of a hand. “It was hard to even get the prosthetic in the right position,” he said, describing how the cumbersome limb turned simple tasks into impossible missions.
Suddenly, the soldier who once led his platoon was unable to make his sons’ peanut-butter-and-jelly sandwiches.
That’s when Lehman met Dr. Todd Kuiken, director of the Center for Bionic Medicine and Amputee Services at the Rehabilitation Institute of Chicago. Kuiken and his plastic surgeon colleague Dr. Gregory Dumanian had been busy co-developing a bionic limb technology known as targeted muscle reinnervation, or TMR for short.
With TMR, surgeons reroute the nerve stumps left over after an amputation to muscles in the chest and upper arm so they can control a prosthetic arm by simply imagining the movement.
Lehman was one of the first amputees to use groundbreaking pattern recognition technology to control his prosthetic arm. It works like speech recognition, according to its creator, neural engineer Levi Hargrove, and relies on a tiny computer the size of a quarter in the bionic arm.
“When we want to use our hands, we don’t think, ‘OK, I’m going to move my elbow, then my shoulder and then my hand.’ No, we just think about it and it goes,” Dumanian said. And achieving this level of intuitive control is where the science gets closer to science fiction.
“I just think of moving my phantom limb, and my prosthesis moves instead,” Lehman said. “I would say it’s at least 75 percent better and more intuitive.”
As Lehman improved the control of his prosthetic, he noticed his phantom pain started to wane — a finding his doctors plan to explore as a cure for the debilitating syndrome.
The cost of surgery and a standard prosthetic run upwards of $150,000 including rehabilitation, according to Dumanian. The bionic arm and pattern recognition technology would increase the cost, Dumanian said, but it might be more cost effective than hand transplantation
But people shouldn’t expect miracles right away, cautions Kuiken.
“Patients need to know it takes about six months for the nerves to grow in,” he said. “It’s OK to wear a regular prosthesis in the meantime, so they’re not left frustrated feeling like they’re chasing their tail.”
Lehman continues to work with scientists to help them improve the technology for wounded warriors coming home.
And how’s that peanut-butter-and-jelly sandwich coming along?
“I’m not sure how I’d compare to someone with two working arms — but I’d be willing to race,” Lehman said.
Copyright 2013 ABC News Radio