Iraq veteran gets powerful new knees

WASHINGTON (CNN) -- Lt. Col. Greg Gadson is not a bionic man, but he does have a new set of powerful knees.

Gadson, an Iraq War veteran, was wounded in 2007 by a roadside bomb and lost both legs above the knees. This week, he became the first person to receive the latest version of battery-powered prosthetic knees.

Gadson demonstrated his new knees during a news conference Thursday at Walter Reed Army Medical Center in Washington.

It's "as if you were driving a school bus and then someone put you in a sports car -- you still know how to drive. There's quite a different feeling," he said.

The Power Knee uses sensors (in contact with the thigh muscle, for example) to anticipate how the user will move, and then shifts itself into position.

"This is the second generation Power Knee," says Tabi King, a spokesperson for Ossur Americas, the manufacturer. "It uses the same type of technology, but it's half the size, makes half the noise, is half the weight and is much more intelligent."

King says the knee is learning in real time to react to a patient so the patient doesn't have to think about walking. "There are sensors and artificial intelligence in the prosthetic that are watching what the body is doing. The biggest benefit is by doing so much work on its own, the amputee doesn't have to think about movement."

Gadson, who had an older model of the powered knees, praised the latest ones.

"These knees are a lot lighter. They're quieter and they have significantly longer battery life," he said, adding that the batteries can last up to 16 hours.

Gadson said he hopes his pioneering efforts will help others.

"If this proves to open a door for other people, that's a tremendous feeling, a tremendous reward. I'm not doing it for that, but I hope that this is a path for people to really expand their lives," he said.

Michael Corcoran, a prosthetist who has been working with Gadson, said he thinks prosthetics of the future will be more powerful. The first Power Knee appeared in 2006. Corcoran expects the improved version to reach the general population in 2010.

"It wasn't designed for military use; it was designed as a knee for everybody," Corcoran said. "We're fortunate enough here to be able to put this technology to its test here at Walter Reed, but as a broader application. You know, a year would be great to see these legs on vascular amputees, because it does improve mobility."

The goal is to come up with technology that adapts to all situations, according to Col. Paul F. Pasquina, one of Gadson's doctors.

"We try to challenge each one of our members into real-life situations where they have to use their prostheses not to just walk in straight directions, but to move in an environment that would be simulations of his home -- going up and down stairs, up and down curbs -- so we try to challenge the technology as much as possible."

Gadson is getting used to the new knees and wears them a few hours daily for now. But he has long-term goals for his new limbs.

"My expectations are that I can do whatever it is I used to do, maybe a little bit different. I have some other considerations, and if I can do those things, then I think that's success."

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