Device Simulates Feeling in Artificial Limbs : Research: Ted Kennedy Jr. and a Solana Beach golfer demonstrate the prosthetic implant, so far used only in legs.

Anew use for electronic technology that gives amputees something like feeling in their prosthetic limbs took its first public steps Thursday.

Showing off the new device were Ted Kennedy Jr., who lost his right leg 15 years ago, and Solana Beach resident Tim Vincent, who lost his left leg five years ago.

The device is used only in artificial legs for now, but researchers are working on an artificial arm and hand, the developers of the device said.

The system uses technology that has been around for several years, said Thomas Guth of the San Diego-based firm RGP Orthopedic Appliance Inc.

RGP will test the prosthetic device, known as the Sabolich “Sense-of-Feel” system, in the San Diego area for the Oklahoma-based Sabolich Prosthetic and Research Center, said John Sabolich, the device’s developer and president of the company.

Sensors are implanted in the ball and heel of an artificial foot. They are linked to an electronic unit, about the size of a pager, that sends signals to the amputee’s nerve endings through electrodes. The nerves send a message to the brain, which registers the message as if it were received from a real leg, Guth said.

“What they feel is a little bit like pins and needles,” Guth said.

The device will most benefit amputees who are unable to use a prosthetic leg with ease. He said some people never really learn to use an artificial leg; they often walk with stiffness or have difficulty maintaining their balance.

“Some patients aren’t ever able to put their head into the leg,” Guth said.

He said the new device will help them by “feeling” the pressure a normal foot would pick up when it touches the floor, giving the wearer a greater sense of balance and mobility.

Guth said recent amputees will benefit most because “they experience the worst phantom sensations.” Phantom sensation is the feeling amputees often experience after a limb has been removed. It can come in the form of cramping where the limb used to be, or it can be pain.

“What we want, then, is sensation, not pain,” Guth said.

The sensory device can also be used to help people with other disabilities or health problem, such as paraplegics and diabetics.

“Diabetics walk ulcers into their feet,” Guth said, because they sometimes lose the feeling in their feet. As a result, they put more pressure on their feet when they walk and develop ulcers or sores that can lead to having a foot amputated.

“We build a foot plate and set the transducers in there and strap the unit around their leg,” he said. “Now they can feel the foot again.”

Kennedy, 29, son of Sen. Edward Kennedy (D-Mass.), lost his right leg to bone cancer at the age of 12. He began using the new device Wednesday and said it was too early to say how it would work while boating, one of his favorite recreations.

However, he said his initial reaction to the device was “an interesting new feeling.”

He described the sensation produced by the unit as a slight shock.

“It takes a little time to get used to,” he said.

“This is a real step in the right direction. . . . They are taking existing technology and applying it to affect people’s quality of life.”

Kennedy called for the involvement of the U.S. government in more research on such devices to help people with disabilities.

With this kind of technology, “people can be active and be independent and lead productive lives,” he said.

Solana Beach resident Tim Vincent is a golfer and will participate in qualifying races for the U.S. Handicapped Ski Team this weekend at Big Bear Lake.

He said the prosthetic leg could lower his golf score.

“When it comes to golfers, there is potential to feel weight distribution,” said Vincent, 40, who also lost a leg to cancer. “I’m looking forward to see where it goes from here.”

After only 24 hours of wearing the new leg, he had some suggestions for improvements. He said he would like to be able to tell if the pressure is on the inside or outside of the foot, as well as to feel more subtle gradations in pressure as the foot rolls off the ground while walking.

Both Guth and Sabolich said they are working on those refinements, plus sensitivity to changes in temperature.

The “Sense-of-Feel” leg will be on the market in about a year, and will cost about $1,400, Guth said.