Computerized knee makes walking a breeze

Statesville Record & Landmark
By J.R. Munoz-McNally
jmcnally@statesville.com
Wednesday, May 9, 2007

Jack Williams is a big, burly, salt-of-the-earth type of guy. The 45-year-old truck driver, who lives in Iredell County, spends some of his spare time bow hunting but most of it is dedicated to hanging out with his three young kids and coaching them in a number of sports.

In recent months, however, he has been on a quest of sorts.
Williams lost his left leg, just above the knee, following a motorcycle accident 19 years ago.

Now he wants to know why insurance companies won’t let him walk and run and climb and otherwise move about the way he knows he could.

“It’s wrong,” he said. “It’s just wrong.”

Williams is referring to the fact that his insurance company refused to pay for a state-of-the-art prosthetic leg, which can cost as much as $75,000.

“How can they deny someone the right to move better, to live better?” he said. “It’s not right.”

Williams was at the Iredell Regional Prosthetic-Orthotic Center Tuesday afternoon getting fitted for a device called a Rheo-Knee made by Ossur Americas.

The prosthesis is the latest in computerized artificial legs. One is being loaned to Williams in the hopes that his insurance company will eventually be persuaded to pay for it or one like it.

“It actually learns who you are and how you walk and it adjusts itself to you,” said Barbara Roesch, an area manager for Ossur. “And the longer you use it the better it gets to know you.”

That’s one smart knee.

“It is the only magnetic-resistance knee on the market,” Roesch said.

She said her company patented the magnetorheological fluid, which is the hydraulic component of the prosthesis.

John Groves has been a double-amputee since he was a toddler, when doctors discovered his “legs just weren’t growing properly.”

“So they told my parents, they had to be removed,” he said.
Groves is a counselor, patient advocate and jack-of-all-trades at the prosthetics center.

He said advances made in leg prosthetics have not come about in an effort to enable people to walk, but to walk better.

“You could put a broom-stick on the end of his leg and he could walk,” Groves said of Williams. “All the technology does is improve the walking and make it more comfortable and less painful.”

He said the Rheo-Knee takes some of the workload off the person.

“These kinds of limbs simulate, as much as is possible right now, the real knee and the anatomical leg,” he said.

Roesch compared them to a person running on different surfaces.

“You know what it’s like to go jogging on soft sand at the beach,” she said. “The sand gives you nothing back but then when get to solid ground, you can feel that return of energy.”

But all that science is not as relevant to Williams as the fact that the leg helps him get up and down hills and stairs and ladders with a lot more confidence and comfort.

After walking up and down between some rails Williams seemed to have quickly acclimated to the new leg.

Roesch said receptors in the knee and ankle joints gather data at a rate of 1,100 pieces per second and begin to get an understanding of gait, weight and other mannerisms of the user’s body to which it is connected.

“How does it feel?” asked Dr. Jim Price, the director of the center. “Even though I know I’m asking for a kind of knee-jerk
reaction.”

Price recognized the pun and then fine-tuned Williams’ borrowed knee with a special type of Allen wrench.

Groves, 45, has been using prosthetic legs for more then four decades.

He said his first set was primitive.

“They took a mold of your leg and then they sent you a chunk of wood,” he said. “And that was your leg.”

But Groves is as quick to point out that while science has advanced the field of prosthetics, it has not pulled off a miracle.

“There is a real misconception out there that these legs can actually do the walking for you,” he said. “They can’t do that but they can make walking easier and what happens while you are walking really affects your entire body.”

Groves said the most advanced prostheses, like the Rheo-Knee, are only for the highest functioning amputees.

He said there are five levels that range from K-4 (athletic) to K-0 (non-ambulatory) and that the computerized knees are only for those in the top two categories.

Williams is in that top tier and wants to keep his high-tech leg.

“I don’t want pity. I don’t want sympathy,” he said. “I just want what’s right. People who are able should be allowed to walk the best way then can.”

**UPDATE 7/27/2007** Mr. Williams' insurance company has paid the claim for his prosthetic knee. Although the insurance company originally denied the claim, Iredell Prosthetic-Orthotic Center fought the decision and won the appeal.