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Three Men Receive Bionic Hands Controlled With Their Minds


The outlook used to be pretty bleak for those who had lost movement in their limbs due to severe nerve damage, but over the last year or so, some incredible advances have been made that are restoring shattered hope for many.

The amazing breakthroughs include spinal cord stimulation that allowed paralyzed men to regain some voluntary control of their legs, a brain implant that enabled a quadriplegic man to move his fingers, and a system that allowed a paralyzed woman to control a robotic armusing her thoughts. Science has definitely been on a roll, but this winning streak isn’t showing any signs of slowing down. Now, the world’s first “bionic reconstructions” have been performed on three Austrian men to help them regain hand function. This technique enabled the newly amputated patients to control prosthetic hands using their minds, allowing them to perform various tasks that most people take for granted.

The men that underwent the procedure had all suffered serious nerve damage as a result of car or climbing accidents, which left them with severely impaired hand function. The nerves that suffered injury were those within a network of fibers supplying the skin and muscles of the upper limbs, known as the brachial plexus. As lead researcher Professor Oskar Aszmann explains in a news release, traumatic events that sever these nerves are essentially inner amputations, irreversibly separating the limb from neural control. While it is possible to operate, Aszmann says the techniques are crude and do little to improve hand function. However, his newly developed procedure is quite different, and is proving to be a success.

Before the men could be fitted with their prosthetic hands, the researchers had to do some preliminary surgical work in which leg muscle was grafted into their arms in order to improve signal transmission from the remaining nerves. After a few months, the fibers had successfully innervated the transplanted tissue, meaning it was time to start the next stage: brain training.

Using a series of sensors placed onto the arm, the men slowly began to learn how to activate the muscle. Next, they mastered how to use electrical nerve signals to control a virtual hand, before eventually moving on to a hybrid hand that was affixed to their non-functioning hand. After around nine months of cognitive training, all of the men had their hand amputated and replaced with a robotic prosthesis that, via sensors, responds to electrical impulses in the muscles.

A few months later, the men had significantly improved hand movement control, which was highlighted by a test of function known as the Southampton Hand Assessment Procedure. As reported in The Lancetbefore the procedure, the men scored an average of 9 out of 100, which soared to 65 using the prosthetic. Furthermore, the men reported less pain and a higher quality of life. For the first time since their injuries, they were able to perform avariety of tasks such as picking up objects, slicing food and undoing buttons with both hands.

“So far, bionic reconstruction has only been done in our center in Vienna,” said Aszmann. “However, there are no technical or surgical limitations that would prevent this procedure from being done in centers with similar expertise and resources.”

The above story is adopted from The Lancet and reprinted from materials provided by NewScientist.

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Patients Choose Amputation to Replace Damaged Hands With Bionics


Marcus Kemeter, who lives in the Lower Austrian town of Hollabrunn, damaged his shoulder in a 1996 motorcycle accident. That year, he had surgery that grafted new nerves to his arm, which restored some function to his shoulder and elbow. Source: Lancet via Bloomberg

Seventeen years after losing the use of his hand in a motorcycle crash, Marcus Kemeter volunteered to have it amputated and replaced with a bionic version.

“It wasn’t hard for me to decide to do the operation,” said Kemeter, 35, a used-car dealer in Austria. “I couldn’t do anything with my hand. The prosthesis doesn’t replace a full hand, but I can do a lot of stuff.”

Kemeter’s artificial hand was made possible by a new medical procedure developed at the Medical University of Vienna, which combines reconstructive surgery with advances in prosthetics and months of training and rehabilitation, according to an article published Wednesday in the Lancet, a U.K. medical journal. The researchers performed the procedure on three Austrian men from 2011 to 2014.

The technique, called bionic reconstruction, offers hope for patients like Kemeter who have brachial plexus injuries, which can result in severe nerve damage and the loss of function in the arms.

The nerves of the brachial plexus start in the neck and branch out to control shoulder, arms and hands. They can be damaged in collisions from car and motorcycle accidents, and in sports like football and rugby. In the past, surgical reconstruction for brachial plexus patients could restore some function in their arms but not hands.

 

Amputated Nerves

The injuries result in an “inner amputation,” permanently separating the hands from neural control, said Oskar Aszmann, a professor of plastic and reconstructive surgery at the Vienna university who is the lead author of the Lancet study.

The damaged limbs “are a biologic wasteland,” Aszmann said in a telephone interview. The solution is transplanting nerves and muscles from the legs into the arm, creating new avenues for signals from the brain.

“We can establish a new signal and we can use these signals to drive a prosthetic hand,” he said.

The process represents a significant step for patients with brachial plexus injuries, said Levi Hargrove, a researcher in prosthetics at the Rehabilitation Institute of Chicago.

“It provides them with an option,” he said. “As mechanical prosthesis become more advanced and more functional, this should only improve.”

The ultimate success of the procedure won’t be known for years and will depend on how often patients use their new hands, said Simon Kay and Daniel Wilks in a Lancet article accompanying the study. Kay is a hand surgeon at the Leeds Teaching Hospital, while Wilks is at The Royal Children’s Hospital in Melbourne.

 

Noisy Protheses

“Compliance declines with time for all prostheses, and motorized prostheses are heavy, need power and are often noisy,” they wrote.

Kemeter, who lives in the Lower Austrian town of Hollabrunn, damaged his shoulder in a 1996 motorcycle accident. That year, he had surgery that grafted new nerves to his arm, which restored some function to his shoulder and elbow. Over the next decade and a half, his arm withered and atrophied, with his fingers permanently clenched.

“I could feel everything but I couldn’t do anything with the hand,” he said.

In 2011, Aszmann transplanted Kemeter’s nerves from his lower leg and muscle from his thigh to his injured forearm. After waiting three months for the nerves to grow back, Kemeter’s arm was connected to a computer, where he could practice manipulating a virtual hand.

 

Forgotten Hand

“The brain has forgotten to use the hand,” Aszmann said. “We have to retrain them.”

The next step was connecting the prosthesis to the new nerves, with Kemeter’s biological hand still in place, to train him to use the device. That helps patients with the decision to amputate, Aszmann said.

“When it’s obvious this mechatronic hand can be of great use to them, then the decision to have the hand amputated is a very easy one,” he said. “If I have to convince someone, they’re not a good patient.”

Finally, after the amputation wounds healed and the prosthesis was fitted, the adjustment to the new appendage took only a few days.

“I can do much more than before,” Kemeter said. “Carrying big things, for example, wasn’t possible with only one hand. Now I can do it.”

Related News and Information: Bionic Hands Move Close to Human Control With Sensation of Touch Innovative Prosthetic Arm From Segway Inventor Cleared by U.S. First Bionic Leg to Harness Nerves Allows Mind Control Movement.

 

The above story is reprinted from materials provided by Bloomberg.