NEWBERG, Ore. (AP) — After losing a leg in Iraq in 2007, Cpl. Garrett Jones told doctors he wanted to have a family and snowboard.

A family. No problem, they said.

But snowboarding for an above-the-knee amputee....

Two years later, 23-year-old Jones of Newberg is spinning 360s at Timberline Ski Area, thanks to an Oregon entrepreneur's perseverance and an innovative prosthetic knee. With the XT9, amputees can take part in sports such as snowboarding, wakeboarding and telemark skiing.

"If I had my pant leg down, you wouldn't know I was an amputee," Jones told The Oregonian newspaper.

The creator of the XT9 is 30-year-old Jarem Frye of Amity. He lost a leg to bone cancer at age 14 in Utah.

He learned to three-track ski - on one leg and a pair of crutches fitted with short skis - and competed at the national level in adaptive ski racing.

Then in 1996, when he was 18, he watched from a ski lift as a telemark skier made turns down the slope below. Tele skiers, who use bindings that keep their heels free, turn by bending their inside knee. He remembers saying, "I'd like to try that someday."

Working as a lift operator in Utah he spent $40 for used tele gear, including leather boots with Rollerblade parts. He strapped in his standard prosthetic leg.

"The first time out, my leg fell off," he said.

Duct tape fixed that. The larger problem was that his walking leg didn't return resistance when he tried to bend his knee to drop into a turn.

He tried to modify his prosthetic leg with an automotive valve from a wrecking yard. Then he tried fitting a mountain-bike RockShox shock absorber into an old walking knee. With help from a machining student at Brigham Young University, he developed a prototype in 2000 that enabled him to turn as if he had two legs.

Friends urged him to market his creation. He sold a few by word of mouth. Then after moving to Oregon in 2006, he and his wife started Symbiotechs USA and the company sold 30 that year. Frye said he has sold 120 more since.

The knee replicates the role of thigh muscles, said James Liston, a prosthetist at Hanger Prosthetics and Orthotics in Salt Lake City. A traditional walking leg prosthesis relies on the user to swing it forward with from the hip before taking a step. But it can't push back if the user wants to bend that leg.

The XTP, in contrast, resists bending and it actually stores energy and pushes back, Liston said.

The knee is designed for certain sports, so it isn't for every day. Frye compares it to walking in a ski boot.

"We don't need to fit every above-the-knee amputee with one, but if there are people who want to do these activities, it's just huge fun," Liston said.

For people such as Jones, the snowboarding Marine, being able to spend time on Mount Hood is as important as walking. He plans to leave the Marines in May.

Then he'd like to spend the summer wakeboarding with his XT9 and working on his tricks at Timberline in preparation for adaptive snowboarding competitions.

"I'm fortunate," he said. "That's how I look at it."

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