Fwd: [RD] CURR: CNN.com: Man controls artificial arms with thought

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http://www.cnn.com/2003/HEALTH/09/25/bionic.arm/index.html  

Brain waves drive man's bionic arm

(CNN) --A man who lost both of his arms in an accident is getting some

high-tech help with an innovative artificial limb that controls movements by

thought.

Two years ago, a healthy Sullivan, 56, was at his job repairing

utility lines when he accidentally touched a live wire, costing him both his

arms up to his shoulders.

Like most amputees, Sullivan was fitted with a traditional artificial

prosthesis, relying on chains and buttons to move his arm. But then doctors

at the Rehabilitation Institute of Chicago offered a " bionic " arm for his

other lost limb, putting him at the forefront of biomechanical technology.

" I didn't really didn't know what was available. It was a scary thing, "

Sullivan remembers. " I thought maybe it would be like the 'Six Million

Dollar Man' [on TV]. "

To get the new arm, Sullivan first underwent surgery to graft existing nerve

endings from his shoulder onto the pectoral muscle on his chest. Those

nerves grew into the muscle after about six months. Electrodes on the graft

can now pick up any thought-generated nerve impulses to the now-absent limb

and transmit those to the mechanical prosthesis, controlling the movements

of the arm.

Sullivan's doctor says this is the first time a nerve-muscle graft has been

used to control an artificial limb.

Now, when Sullivan thinks about closing his hand, the nerve that used to

make the hand close spurs a little piece of his chest muscle to contract,

said Dr. Todd Kuiken, one of Sullivan's doctors at the Rehabilitation

Institute of Chicago. Sensors over that muscle then tell the hand to close

via tiny connecting wires.

" This is 1920s surgery but it's for a 21st century application, " said

Kuiken. " So what's really novel about this is not so much the surgical

technique but the reason for doing the surgery and using it to help control

artificial limbs and make them work better. "

New wave technology

Some researchers have used electrodes implanted in the brain or in the

scalp, while others have experimented with detectors outside the body, such

as in Sullivan's case. But the basic idea behind neuroprosthetic devices is

the same: creating communication between the brain and the outside object

that needs to be moved.

" To move something, you have to get a command signal from the brain to [an

object,] whether it's a wheelchair, robot or your own arm, " explains Dr.

Schmit, an assistant professor of biomedical engineering at Marquette

University.

The technology has the possibility to dramatically change those that have

lost limbs or who are paralyzed. Some of the thought-driven devices being

developed could navigate wheelchairs, control a robotic arm's movement, or

even move a computer mouse, according to Schmit.

" If you can provide to someone who can't move access to a computer, it opens

a lot of doors, " Schmit says. " The brain can change to new circumstances.

The body has an amazing ability to learn and adapt. "

About 8 percent of the estimated 387,500 amputees in the United States are

those that have lost their arms, according to the Northwestern University

Prosthetic-Orthotic Center.

" With these new prostheses, these patients can now use their nerves in the

natural way to control their artificial hand so that you have a more natural

feel to its use, " Kuiken said. " It's faster and more agile. "

For now, the medical procedure performed on Sullivan is limited to amputated

arms. The hope is that one day it can be applied to other limbs as well.

Sullivan said the experimental surgery was worth the uncertainty at first if

it can help others later.

" If this benefits another person then it is well worth it, " Sullivan said.

" And it has benefited me so I'm well satisfied. "

CNN medical producer Gajilan contributed to this report.

 

 

 

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