Two steps forward

He's Walter Reed's bionic man, a wounded warrior who walks on a pair of new battery-powered prosthetic legs outfitted with some of the most high-tech gizmos around.

No, Army Lt. Col. Greg Gadson can't move like he did when he was a linebacker on West Point's football team or a battalion commander in Iraq. But even after just a few days on his new legs, which have embedded sensors that gauge his weight and speed and can help correct missteps, he's walked a mile under his own power.

He is quicker with his new legs, more nimble. When he stumbles, the legs have helped right him. And at a recent demonstration at Walter Reed Army Medical Center, he proclaimed that they are the closest yet to "the feeling of a normal leg" since he lost both of his in Iraq almost two years ago.

"It was like you were driving a school bus and someone put you in a sports car," he said. "I can definitely see myself doing things I wouldn't do -- like shopping."

The technology behind the Power Knee is the next step in a rapidly changing field that has moved to the forefront of military medicine during the wars in Iraq and Afghanistan. As of April 1, 871 amputee patients wounded in combat had been treated in U.S. military facilities. The number of amputees grew from 157 in 2004 to 207 in 2007. Last year, the figure dropped to 82.

For the waves of wounded warriors still streaming home from the battlefield, the legs will offer a chance to recapture a sense of independence, officials said, and with time and practice and patience, a chance to reach the goal Gadson has set for himself: "to walk when I want to walk, and where I want to walk."

Gadson, 43, who lives at Fort Belvoir, Va., is the first to try out the prosthetic, which was developed by Ossur, an Icelandic company. Walter Reed officials said they hope the Power Knee soon will be in much wider distribution for soldiers and civilians.

Gadson was wounded the way most soldiers in Iraq are: when his convoy was hit by a roadside bomb. It was May 7, 2007, and Gadson, then with the 2nd Battalion, 32nd Field Artillery, was on his way back from a memorial service for two of his soldiers. Within days, his left leg was amputated above the knee, and later, so was his right.

The married father of two teenagers said that, initially, the loss of his legs was traumatic. But he decided to accept it, and once "intellectually you know your legs aren't coming back, you have to decide what you want out of life," he said.

The new prosthetics are lighter, more stable and quieter than their predecessors. And because they can predict movement as well as react to it, they are smarter, too, Walter Reed officials said.

"It's radically different from any prosthetic available today," said Mike Corcoran, a certified prosthetist who has worked with Gadson through his rehabilitation.

Corcoran can wirelessly "log in" to Gadson's knees and tell, in real time, whether his gait is symmetrical, how long his strides are and whether he's walking up or down hill. With that information, Corcoran can adjust settings, giving Gadson a better fit and smoother ride. The legs even have an odometer in them, "so I know what he's done over the weekend. If I tell him to walk four miles and then see that he hasn't, he's busted," Corcoran said.

Last Friday was Gadson's first day on the legs, and he was, he said, a little shaky.

"I fell a lot," he said. "I've found a new humility."

On Monday, he walked a mile.

On Tuesday, "I didn't fall at all."

On Thursday, he showed off the legs before a gaggle of reporters. With the help of two canes and a safety rope to keep him from falling, he strode around a track at his new average: 80 steps a minute.

Next up is learning to walk with one cane instead of two, he said.

"Then we'll start to tackle stairs."