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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.

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‘Cyborg’ spinal implant could help paralysed walk again

February 8, 2015 Leave a comment

It might seem like science fiction but a new implant which attaches directly to the spine could help paralysed people walk again

The implant is so effective because it mimics the soft tissue around the spine so that the body does not reject its presence.

Paralysed patients have been given new hope of recovery after rats with severe spinal injuries walked again through a ‘groundbreaking’ new cyborg-style implant.

In technology which could have come straight out of a science fiction novel or Hollywood movie, French scientists have created a thin prosthetic ribbon, embedded with electrodes, which lies along the spinal cord and delivers electrical impulses and drugs.

The prosthetic, described by British experts as ‘quite remarkable’, is soft enough to bend with tissue surrounding the backbone to avoid discomfort.

Paralysed rats who were fitted with the implant were able to walk on their own again after just a few weeks of training.

Researchers at the Ecole Polytechnique Fédérale de Lausanne are hoping to move to clinical trials in humans soon. They believe that a device could last 10 years in humans before needing to be replaced.

The implant, called ‘e-Dura’, is so effective because it mimics the soft tissue around the spine – known as the dura mater – so that the body does not reject its presence.

“Our e-Dura implant can remain for a long period of time on the spinal cord or cortex,” said Professor Stéphanie Lacour.

“This opens up new therapeutic possibilities for patients suffering from neurological trauma or disorders, particularly individuals who have become paralyzed following spinal cord injury.”

Previous experiments had shown that chemicals and electrodes implanted in the spine could take on the role of the brain and stimulate nerves, causing the rats’ legs to move involuntarily when they were placed on a treadmill.

But this is the first study to show a simple gadget can help rats walk again and be tolerated by the body.

Scientists have struggled to find a device which will sit next to the spine or brain because both are surrounded by a protective envelope of tissue which the hard surface of implants can rub against, causing inflammation and scar tissue

The electronic ribbon is placed directly onto the spinal cord.

However the new gadget is flexible and stretchy enough that it can be placed directly onto the spinal cord. It closely imitates the mechanical properties of living tissue, and can simultaneously deliver electric impulses and drugs which activate cells.

The implant is made of silicon and covered with gold electric conducting tracks that can be pulled and stretched. The electrodes are made of silicon and platinum microbeads which can also bend in any direction without breaking.

Writing in the journal Science, where the results were published, science writer Robert Service said: “Soft flexible nerves connected to unyielding silicon and metal – the combination has spawned many a Hollywood cyborg.

“The implants Lacour’s team created still have to be wired to the outside world to operate, but she and her colleagues are designing wireless versions of the technology. Watch out, Hollywood, reality is catching up.”

The research was praised by British scientists.

“The work described here is a groundbreaking achievement of technology, which could open a door to a new era in treatment of neuronal damage,” said Dr Duško Ilić, Reader in Stem Cell Science at King’s College London.

“Until now, the most advanced prostheses in intimate contact with the spinal cord caused quite substantial damage to tissue in just one week due to their stiffness.

“There is still a long way to go before we may see any practical use of such neuroprostheses in humans. But it may be that it is something that could potentially be developed for use in humans in the foreseeable future.”

Prof John Hunt, Head of Unit of Clinical Engineering, University of Liverpool, added: “This study in rats is an interesting one and it could have the potential to be quite promising in terms of being applicable to people with spinal injuries.”

The implant has been primarily tested in cases of spinal cord injury in paralyzed rats but researchers believe it could eventually be used in epilepsy, Parkinson’s disease and pain management.

The scientists are planning to move towards clinical trials in humans within the next few years.

Additional Link:

NCBI – ‘Bionic’ spinal implant helped paralysed rats walk.

 

The research was published in the journal Science.

The above story is reprinted from materials provided by The Telegraph.