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Three Men Receive Bionic Hands Controlled With Their Minds

March 11, 2015 Leave a comment

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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Hand Transplantations and Bionic Prostheses


Recently I attended an international medical student congress, Medical Student Journal Club – Pro et Contra, which took place on 23. and 24. May 2014 in Ljubljana, Slovenia.

It was a great congress, with a lot of interesting debates preesented by great speakers.

Myself, I have also registred as an active speaker, together with a colleague of mine, Barbara Šijaković. We debated on topic “Reconstructive surgery should focus on development of cadaver body parts transplantation rather than bionic prosthesis implantation“.

Below is a transcript of our debate.

And just for elaboration, the whole keynote was actually made with only videos tu support theses.


Reconstructive surgery should focus on development of cadaver body parts transplantation rather than bionic prosthesis implantation

Luka: Hello, it’s me up here again. So, I thought I could start with an old Marx brothers joke. No wonder it looks like the same room, because it is the same room. Ok, it doesnt go…

Well, since it’s Saturday afternoon and this is the last debate of this congress, we’ll try to be as interesting and short as possible. My name is Luka, on my left a college of mine, Barbara, and, already introduced, our mentor, Nina Suvorov, MD.

Before we actually start with the debate, let us ask you a question. Imagine you’ve lost your hand sometime in the past and now you are presented with two options. Either hand transplantation or bionic prosthesis. Which would you, right now, choose. Would you go for hand transplantation, or would you rather go with a bionic prosthesis. How many of you would choose hand transplantation? And how many bionic prosthesis? Interesting; 60% for bionics and 40% for transplantation. We’ll keep that number in mind.

Barbara: Now, before we begin, let’s clear the terms. Luka, could you tell us what a reconstructive transplant is?

Luka: Thank you, Barbara. A reconstructive transplant, or also called a composite tissue allograft, is an operation that involves transplantation of bone, tissue, muscle and blood vessels. According to WHO “transplantation is the transfer or rather engraftment of human cells, tissues or organs from a donor to a recipient with the aim of restoring function(s) in the body. And in cases when transplantation is performed between different species, e.g. animal to human, it is named xenotransplantation.

Now, Barbara, would you care to briefly explain what a bionic prosthesis is and how it works?

Barbara: Bionic creativity engineering is basically implementation of biological systems in the developing modern technology. Bionic hand isn’t just the hook. It mimics the real human hand. In some cases bionic hand even superposes human hand, as we shall see later.

There are different bionic prostheses, today I’ll talk about i-Limb Ultra, the one most advanced for now.

Here is how it looks: we can see power button here, the digits are motorized. It’s made out of plastic, titanium and silicone.

And just some mechanical properties…

This is a myoelectric prosthesis, which means it uses electrical sensors to detect contractions in the selected muscles of the residual limb. These contractions are than translated into movement of the bionic hand by a specific algorithms.

Luka: Ok, so which is better? Let’s start with transplantations of the hand. We will focus mainly on the hand, since leg prosthetics are nearly perfect, but with hand it’s different. You have many small and fine movements that are incorporated in every day’s life and you simply cannot function without a hand.

Just some short history for the beginning. The first hand transplant was actually performed in Ecuador in 1964, but the patient suffered from transplant rejection after only two weeks. Then, there was basically a long period of nothing. Up until January 1999. The first successful hand transplantation. Now, you should notice, we are talking about transplantation, not about replantation. The first successful replantation was performed in Shanghai, China, in January 1963.

So, in January 1999 the first person (a baseball player) underwent an operation. This kind of operation is probably one of the longest there is. It takes approximately 12 to 16 hours. In comparison, a typical heart transplant takes 6 to 8 hours and a liver transplant, 8 to 12 hours.

Hand transplantation is an extremely complex procedure, but may not be as difficult as a hand replantation in that a replantation usually involves crushed or mangled bones, tendons, and ligaments.

Barbara: Would you care to elaborate on how this is done? Read more…