Bionic prosthesis restores sense of touch and movement for amputees
It was a scene in the iconic 1980 Star Wars film, "The Empire Strikes Back": A young Jedi receives a prosthetic hand capable of touch.
Now, nearly 40 years later, that sci-fi technology is a reality.
Amanda Kitts loves traveling the world with her husband. But a car accident in 2006 changed her life forever. She was driving home from work one day and a pickup truck collided into her car.
“His tire flew off and his axel came in through my window and ripped my arm off,” she explains.
The accident didn’t only take her arm, but also her ability to do simple everyday activities.
“Silly little things like putting toothpaste on a toothbrush or even trying to put on a bra,” she says.
Paul Marasco of the Cleveland Clinic thought Amanda would be a perfect candidate to try a new type of bionic prosthesis that restores the sense of touch and movement sensation for upper limb amputees. All candidates must have already undergone a targeted nerve reinnervation, which is a procedure to redirect amputated nerves to new muscle in the arm or chest.
“When we vibrate those muscles, it provides an illusion of movement,” Marasco explains.
It allows patients to “sense that their hand is moving in very complex and naturalistic ways,” Amanda says.
Patients feel when their hand opens and closes and how hard they squeeze something when they have the prosthesis on. Marasco also says this technology allows amputees to see this prosthesis as part of their body. Amanda agrees.
“You know when you get a new sense that you haven’t had for so many years. It’s been 12 years since I lost my arm. It’s another movement towards having a real hand, having a real arm. It’s amazing actually,” Amanda says.
The patients in this trial have a prototype of the prosthesis, but it isn’t currently out in the market yet.
Marasco is also exploring ways to expand this technology to patients who have lost a leg.
TOPIC: RESTORING TOUCH FOR AMPUTEES: SCI-FI BECOMES REALITY!
REPORT: MB #4423
BACKGROUND: Amputation is the surgical removal of all or part of a limb or extremity such as an arm, leg, foot, hand, toe, or finger. About 1.8 million Americans are living with amputations. Amputation of the leg is the most common amputation surgery. There are many reasons an amputation may be necessary. The most common is poor circulation because of damage or narrowing of the arteries, called peripheral arterial disease. Without adequate blood flow, the body's cells cannot get oxygen and nutrients they need from the bloodstream. As a result, the affected tissue begins to die and infection may set in. Other reasons might be a severe accident, cancer, serious infection, thickening of nerve tissue, or frostbite.
AFTERMATH: During the amputation procedure, doctors will remove any diseased tissue or crushed bone and seal off blood vessels and nerves. Adapting to amputation is a challenge, not only physically, but mentally as well. After an amputation, people can be prone to suffering from body image issues. Also, an amputation can affect a person’s ability to take part in the same social activities, leisure pursuits or hobbies that they would have otherwise enjoyed. Social withdrawal can often result, leaving the injured person feeling isolated. Their personal relationships can be heavily affected, as some amputees completely avoid contact with their friends and peers, or even exhibit outbursts of anger at those loved ones they are still in contact with; most likely those who are helping them and providing care.
NEW TECHNOLOGY: Paul Marasco Ph.D., an Associate Staff Scientist in Biomedical Engineering in the Lerner Research Institute of Cleveland Clinic, and Principle Investigator in the Advanced Platform Technology Center of the Louis Stokes Cleveland VA Medical Center said that some amputees are afraid of touching others with their prosthesis, because they cannot tell how much strength they are using. With the new touch system, amputees can regain a sense they have lost. Marasco explained, “They’ve taken out their nerves after the amputation and then redirected them to new muscle and skin sites. When the amputee thinks “I want to move my hand”, little parts of their reinnervated muscles twitch and we can read that with a computer. It pushes on the reinnervated skin and then they feel the sensation in their brain as though it’s their fingertip and then they map that out to the prosthesis. They see their finger being touched and they feel like that’s their finger.”
(Source: Paul Marasco Ph.D)