DOCTORS WIRED A PROSTHETIC HAND DIRECTLY INTO A WOMAN’S NERVES

JON CHRISTIAN__FILED UNDER: ENHANCED HUMANS
VICTOR TANGERMANN

Sans Hand

In a world first, doctors in Sweden say they’ve wired a prosthetic hand directly into a woman’s nervesallowing her to move its fingers with her mind and even feel tactile sensations.

The hand is an enormous step up from existing prostheses, which often rely on electrodes placed on the outside of the skin — and it could herald a future in which robotic devices interface seamlessly with our bodies.

Nerve Case

Researchers at Chalmers University of Technology and biotech firm Integrum AB created the prosthetic hand as part of DeTOP, an ambitious European research program on prosthetic limbs.

Surgeons anchored the hand to the woman’s forearm bones using titanium implants. They connected an array of 16 electrodes directly to her nerves and muscles, allowing her to control the hand with her mind — and, according to photos, use it to tie shoelaces and type on a laptop computer.

“The breakthrough of our technology consists on enabling patients to use implanted neuromuscular interfaces to control their prosthesis while perceiving sensations where it matters for them, in their daily life,” Chalmers researcher Ortiz Catalan said in a press release.

Virtual Light

Electronics wired straight into a human nervous system allow for mind-bending new ways to interact with technology. A video released by the Swedish researchers even shows the woman using the implant to flex a virtual hand on a computer screen — before the actual physical hand was installed.

For decades, cyborg limbs like those depicted in “Star Wars” or “Neuromancer” seemed relegated to the realm of science fiction. New research shows that they’re already here — just not yet widely available.

Source of the Article: https://futurism.com/the-byte/prosthetic-hand-womans-nerves

Woman is given first robotic hand that allows user to touch and feel

The battery-powered limb could be available on the NHS within a few years, British researchers say

By Martin Bagot Health And Science Correspondent

(Image: Dr Max Ortiz Catalan)

The first robotic hand that enables the amputee to touch and feel has been given to a Swedish woman.

The revolutionary mechanical limb is controlled by electrodes connected to nerves and muscles in the stump

Signals pass “tactile sensations” to the nerves while allowing the body to control a range of motions similar to a real hand.

British researchers involved in the EU-funded project say the battery-powered limb could be available on the NHS within a few years.

The prosthetic could soon be available on the NHS (Image: PA)

Dr Luca Citi, of Essex University, said: “This is a big thing. Currently amputees would have to watch their prosthetic hand if they are picking up, say a plastic cup, to check they are not crushing it.

Source of the Article: https://www.mirror.co.uk/science/woman-given-first-robotic-hand-13956377

Schoolgirl with no hand gets bionic arm as Christmas gift from mystery donor

Evie Lambert, 11, will be able to open Christmas gifts for the first time thanks to ‘a real-life Santa’

An anonymous donor has gifted Evie a 3D-printed prosthetic arm (Image: Mercury Press & Media)

A girl has been given the perfect early Christmas gift of a bionic arm and will be able to open her presents unaided for the first time.

Evie Lambert, 11, was born with no left hand and was delighted when a kind-hearted anonymous donor paid for her £10,000 3D-printed arm.

Now Evie is looking forward to opening her presents on Christmas morning with her “Frozen” themed arm.

She said: “I want to say a big thank you to the donor. It is the best Christmas present ever.

“It will really help me to do things that I struggled to do before. It feels really comfortable wearing it and the hand opens and closes like a real hand. I’d love to get make-up for Christmas and now I’ll be able to put mascara on.”

Her mum Sally, 47, of Huddersfield, West Yorks said: “She couldn’t have wished for a better Christmas present.

She will now be able to open – and help wrap – presents this Christmas (Image: Mercury Press & Media)
Evie was born with no left hand (Image: Mercury Press & Media)

“If she could have put anything on her wish list it would have been this. The donor is like a real-life Santa.

“It gives her functionality. It’s the simple things that she’s enjoying doing now – like being able to hold and open a can of pop, brushing her hair, opening a lip balm or putting clothes on a hanger, things that we take for granted.

Evie Lambert with brother Henry (Image: Mercury Press & Media)

“When she does it her face just lights up.

“The most amazing thing will be seeing her open her presents on Christmas day. I’m also going to have her help me wrap Christmas gifts.”

Sally and her husband Duncan, 49, found out at the 20-week scan that Evie had no left hand.

Her arm has a Frozen design theme (Image: Mercury Press & Media)

Sally, who also has an eight-year-old son Henry, said: “We have had incidents where people have called her names and there have been stares, but I think she’s built up a resilience to it.”

The family heard about Bristol-based Open Bionics at a conference in September.

Soon after they got a call to say a donor had paid for a prosthetic for Evie, whose arm was fitted in November.

Sally said: “It’s the kind of thing you think happens to other people. It’s amazing.

“It’s such an act of kindness – you don’t think these people exist.”

Source of the article: https://www.mirror.co.uk/news/uk-news/school-girl-no-hand-gets-13755653

Prosthetics experts of the future will be trained in Salford in a UK first

A centre of excellence aims to train up to 60 people to doctoral level

By Paul Britton

Prosthetics experts of the future will be trained in Salford (Image: University of Salford)

Prosthetics experts of the future will be trained in Salford at an £11m university centre of excellence.

The University of Salford has announced up to 60 people will be trained to doctoral level over the next eight years to address a skills gap at home and abroad.

The University of Salford is one of only two universities in the UK running an undergraduate programme in prosthetics and orthotics, which is the provision of equipment like spinal braces and specialist footwear, and the centre will be the first in the UK.

Hailed as a global centre of excellence, it will seek to address a worldwide rise in demands for artificial limbs and other devices.

Worldwide demand for artificial limbs is growing (Image: University of Salford)

The country’s principal prosthetics and orthotics research centres, at Imperial College London, the University of Strathclyde and the University of Southampton, will join forces with the University of Salford.

The project partners the centre with 27 industry and clinical collaborators, including two of the largest manufacturers of prosthetic and orthotic devices in the world and the global leader in research, Northwestern University in America.

Malcolm Granat, Professor of health and rehabilitation sciences at the University of Salford, will be the centre’s director.

He said: “Globally, 100 million people need prosthetic and orthotic devices and this is rising rapidly. With most users now being of a working age, there is an ever-increasing need to develop more sophisticated devices suited to a range of diverse needs.

The centre will be the first of its kind in the country (Image: The University of Salford)

“There is a woeful shortage of research engineers who have a deep understanding of these challenges. Our expectation is that this new centre will create a talented workforce, who will be equipped to produce local and global solutions to transform lives.”

Many students are expected to be graduates in engineering, the university said, with the remainder coming from industry and some from clinical backgrounds.

The World Health Organisation estimates more than two billion people are expected to require health-related devices by 2030.

Vice Chancellor of the University of Salford, Professor Helen Marshall, said: “To become the first centre for doctoral training of prosthetists and orthotists in the UK is hugely prestigious and a fantastic result for the team.

“The University of Salford prides itself on establishing mutually beneficial partnerships with industry and this particular initiative will not only strengthen the prosthetics and orthotics industry but have a real world impact on people living with serious injury both in the UK and globally.”

Source of the Article: https://www.manchestereveningnews.co.uk/news/greater-manchester-news/prosthetics-centre-salford-university-limbs-15778659

Low-cost prosthetic foot mimics natural walking

New design can be tuned to an individual’s body weight and size.

Jennifer Chu | MIT News Office

Prosthetic limb technology has advanced by leaps and bounds, giving amputees a range of bionic options, including artificial knees controlled by microchips, sensor-laden feet driven by artificial intelligence, and robotic hands that a user can manipulate with her mind. But such high-tech designs can cost tens of thousands of dollars, making them unattainable for many amputees, particularly in developing countries.

Now MIT engineers have developed a simple, low-cost, passive prosthetic foot that they can tailor to an individual. Given a user’s body weight and size, the researchers can tune the shape and stiffness of the prosthetic foot, such that the user’s walk is similar to an able-bodied gait. They estimate that the foot, if manufactured on a wide scale, could cost an order of magnitude less than existing products.

The custom-designed prostheses are based on a design framework developed by the researchers, which provides a quantitative way to predict a user’s biomechanical performance, or walking behavior, based on the mechanical design of the prosthetic foot.

“[Walking] is something so core to us as humans, and for this segment of the population who have a lower-limb amputation, there’s just no theory for us to say, ‘here’s exactly how we should design the stiffness and geometry of a foot for you, in order for you to walk as you desire,’” says Amos Winter, associate professor of mechanical engineering at MIT. “Now we can do that. And that’s super powerful.”

Winter and former graduate student Kathryn Olesnavage report details of this framework in IEEE’s Transactions on Neural Systems and Rehabilitation. They have published their results on their new prosthetic foot in the ASME Journal of Mechanical Design, with graduate student Victor Prost and research engineer William Brett Johnson.

Following the gait

In 2012, soon after Winter joined the MIT faculty, he was approached by Jaipur Foot, a manufacturer of artificial limbs based in Jaipur, India. The organization manufactures a passive prosthetic foot, geared toward amputees in developing countries, and donates more than 28,000 models each year to users in India and elsewhere.

“They’ve been making this foot for over 40 years, and it’s rugged, so farmers can use it barefoot outdoors, and it’s relatively life-like, so if people go in a mosque and want to pray barefoot, they’re likely to not be stigmatized,” Winter says. “But it’s quite heavy, and the internal structure is made all by hand, which creates a big variation in product quality.”

The organization asked Winter whether he could design a better, lighter foot that could be mass-produced at low cost.

“At that point, we started asking ourselves, ‘how should we design this foot as engineers? How should we predict the performance, given the foot’s stiffness and mechanical design and geometry? How should we tune all that to get a person to walk the way we want them to walk?’” Winter recalls.

The team, led by Olesnavage, first looked for a way to quantitatively relate a prosthesis’ mechanical characteristics to a user’s walking performance — a fundamental relationship that had never before been fully codified.

While many developers of prosthetic feet have focused on replicating the movements of able-bodied feet and ankles, Winter’s team took a different approach, based on their realization that amputees who have lost a limb below the knee can’t feel what a prosthetic foot does.

“One of the critical insights we had was that, to a user, the foot is just kind of like a black box — it’s not connected to their nervous system, and they’re not interacting with the foot intimately,” Winter says.

Instead of designing a prosthetic foot to replicate the motions of an able-bodied foot, he and Olesnavage looked to design a prosthetic foot that would produce lower-leg motions similar to those of an able-bodied person’s lower leg as they walk.

“This really opened up the design space for us,” Winter says. “We can potentially drastically change the foot, so long as we make the the lower leg do what we want it to do, in terms of kinematics and loading, because that’s what a user perceives.”

With the lower leg in mind, the team looked for ways to relate how the mechanics of the foot relate to how the lower leg moves while the foot is in contact with the ground. To do this, the researchers consulted an existing dataset comprising measurements of steps taken by an able-bodied walker with a given body size and weight. With each step, previous researchers had recorded the ground reaction forces and the changing center of pressure experienced by a walker’s foot as it rocked from heel to toe, along with the position and trajectory of the lower leg.

Winter and his colleagues developed a mathematical model of a simple, passive prosthetic foot, which describes the stiffness, possible motion, and shape of the foot. They plugged into the model the ground reaction forces from the dataset, which they could sum up to predict how a user’s lower leg would translate through a single step.

With their model, they then tuned the stiffness and geometry of the simulated prosthetic foot to produce a lower-leg trajectory that was close to the able-bodied swing — a measure they consider to be a minimal “lower leg trajectory error.”

“Ideally, we would tune the stiffness and geometry of the foot perfectly so we exactly replicate the motion of the lower leg,” Winter says. “Overall, we saw that we can get pretty darn close to able-bodied motion and loading, with a passive structure.”

Evolving on a curve

The team then sought to identify an ideal shape for a single-part prosthetic foot that would be simple and affordable to manufacture, while still producing a leg trajectory very similar to that of able-bodied walkers.

To pinpoint an ideal foot shape, the group ran a “genetic algorithm” — a common technique used to weed out unfavorable options, in search of the most optimal designs.

“Just like a population of animals, we made a population of feet, all with different variables to make different curve shapes,” Winter says. “We loaded them into simulation and calculated their lower leg trajectory error. The ones that had a high error, we killed off.”

Those that had a lower error, the researchers further mixed and matched with other shapes, to evolve the population toward an ideal shape, with the lowest possible lower leg trajectory error. The team used a wide Bezier curve to describe the shape of the foot using only a few select variables, which were easy to vary in the genetic algorithm. The resulting foot shape looked similar to the side-view of a toboggan.

Olesnavage and Winter figured that, by tuning the stiffness and shape of this Bezier curve to a person’s body weight and size, the team should be able to produce a prosthetic foot that generates leg motions similar to able-bodied walking. To test this idea, the researchers produced several feet for volunteers in India. The prostheses were made from machined nylon, a material chosen for its energy-storage capability.

“What’s cool is, this behaves nothing like an able-bodied foot — there’s no ankle or metatarsal joint — it’s just one big structure, and all we care about is how the lower leg is moving through space,” Winter says. “Most of the testing was done indoors, but one guy ran outside, he liked it so much. It puts a spring in your step.”

Going forward, the team has partnered with Vibram, an Italian company that manufactures rubber outsoles — flexible hiking boots and running shoes that look like feet. The company is designing a life-like covering for the team’s prosthesis, that will also give the foot some traction over muddy or slippery surfaces. The researchers plan to test the prosthetics and coverings on volunteers in India this spring.

Winter says the simple prosthetic foot design can also be a much more affordable and durable option for populations such as soldiers who want to return to active duty or veterans who want to live an active lifestyle.

“A common passive foot in the U.S. market will cost $1,000 to $10,000, made out of carbon fiber. Imagine you go to your prosthetist, they take a few measurements, they send them back to us, and we send back to you a custom-designed nylon foot for a few hundred bucks. This model is potentially game-changing for the industry, because we can fully quantify the foot and tune it for individuals, and use cheaper materials.”

This research was funded, in part, by the MIT Tata Center for Technology and Design.

Source of Article: http://news.mit.edu/2018/low-cost-prosthetic-foot-mimics-natural-walking-0627

Surgical technique improves sensation, control of prosthetic limb

Surgical technique improves sensation, control of prosthetic limb
A schematic demonstrating the control mechanism of the neural interface. The subject’s leg movement is sent to the prosthesis as an EMG signal (blue arrows), and the movement of the prosthesis is communicated back to the subject’s nervous system (green arrow). Credit: T.R. Clites et al., Science Translational Medicine (2018)

Humans can accurately sense the position, speed, and torque of their limbs, even with their eyes shut. This sense, known as proprioception, allows humans to precisely control their body movements.

Despite significant improvements to prosthetic devices in recent years, researchers have been unable to provide this essential sensation to people with artificial limbs, limiting their ability to accurately control their movements.

Researchers at the Center for Extreme Bionics at the MIT Media Lab have invented a new neural interface and communication paradigm that is able to send movement commands from the central nervous system to a robotic prosthesis, and relay proprioceptive feedback describing movement of the joint back to the central nervous system in return.

This new paradigm, known as the agonist-antagonist myoneural interface (AMI), involves a novel surgical approach to  amputation in which dynamic muscle relationships are preserved within the amputated limb. The AMI was validated in extensive preclinical experimentation at MIT prior to its first surgical implementation in a human patient at Brigham and Women’s Faulkner Hospital.

In a paper published today in Science Translational Medicine, the researchers describe the first human implementation of the agonist-antagonist myoneural interface (AMI), in a person with below-knee amputation.

The paper represents the first time information on joint position, speed, and torque has been fed from a prosthetic limb into the nervous system, according to senior author and project director Hugh Herr, a professor of media arts and sciences at the MIT Media Lab.

“Our goal is to close the loop between the peripheral nervous system’s muscles and nerves, and the bionic appendage,” says Herr.

To do this, the researchers used the same biological sensors that create the body’s natural proprioceptive sensations.

The AMI consists of two opposing muscle-tendons, known as an agonist and an antagonist, which are surgically connected in series so that when one muscle contracts and shortens—upon either volitional or electrical activation—the other stretches, and vice versa.

This coupled movement enables natural biological sensors within the muscle-tendon to transmit electrical signals to the central nervous system, communicating muscle length, speed, and force information, which is interpreted by the brain as natural joint proprioception.

“Because the muscles have a natural nerve supply, when this agonist-antagonist muscle movement occurs information is sent through the nerve to the brain, enabling the person to feel those muscles moving, both their position, speed, and load,” he says.

By connecting the AMI with electrodes, the researchers can detect electrical pulses from the muscle, or apply electricity to the muscle to cause it to contract.

“When a person is thinking about moving their phantom ankle, the AMI that maps to that bionic ankle is moving back and forth, sending signals through the nerves to the brain, enabling the person with an amputation to actually feel their bionic ankle moving throughout the whole angular range,” Herr says.

Decoding the electrical language of proprioception within nerves is extremely difficult, according to Tyler Clites, first author of the paper and graduate student lead on the project.

“Using this approach, rather than needing to speak that electrical language ourselves, we use these  to speak the language for us,” Clites says. “These sensors translate mechanical stretch into electrical signals that can be interpreted by the brain as sensations of position, speed, and force.”The AMI was first implemented surgically in a human patient at Brigham and Women’s Faulkner Hospital, Boston, by Matthew Carty, one of the paper’s authors, a surgeon in the Division of Plastic and Reconstructive Surgery, and an MIT research scientist.

In this operation, two AMIs were constructed in the residual limb at the time of primary below-knee amputation, with one AMI to control the prosthetic ankle joint, and the other to control the prosthetic subtalar joint.

“We knew that in order for us to validate the success of this new approach to amputation, we would need to couple the procedure with a novel prosthesis that could take advantage of the additional capabilities of this new type of residual limb,” Carty says. “Collaboration was critical, as the design of the procedure informed the design of the robotic limb, and vice versa.”

Toward this end, an advanced prosthetic limb was built at MIT and electrically linked to the patient’s peripheral nervous system using electrodes placed over each AMI muscle following the amputation surgery.

Surgical technique improves sensation, control of prosthetic limb
Credit: Massachusetts Institute of Technology

The researchers then compared the movement of the AMI patient with that of four people who had undergone a traditional below-knee amputation procedure, using the same advanced prosthetic limb.

They found that the AMI patient had more stable control over movement of the prosthetic device and was able to move more efficiently than those with the conventional amputation. They also found that the AMI patient quickly displayed natural, reflexive behaviors such as extending the toes toward the next step when walking down a set of stairs.

These behaviors are essential to natural human movement and were absent in all of the people who had undergone a traditional amputation.

What’s more, while the patients with conventional  reported feeling disconnected to the prosthesis, the AMI patient quickly described feeling that the bionic ankle and foot had become a part of their own body.

“This is pretty significant evidence that the brain and the spinal cord in this patient adopted the prosthetic leg as if it were their biological limb, enabling those biological pathways to become active once again,” Clites says. “We believe proprioception is fundamental to that adoption.”

Surgical technique improves sensation, control of prosthetic limb
Credit: Massachusetts Institute of Technology

The researchers have since carried out the AMI procedure on nine other below-knee amputees and are planning to adapt the technique for those needing above-knee, below-elbow, and above-elbow amputations.

“Previously humans have used technology in a tool-like fashion,” Herr says. “We are now starting to see a new era of human-device interaction, of full neurological embodiment, in which what we design becomes truly part of us, part of our identity.”

Source of the Article: https://medicalxpress.com/news/2018-05-surgical-technique-sensation-prosthetic-limb.html

Source of the Article: https://medicalxpress.com/news/2018-05-surgical-technique-sensation-prosthetic-limb.html

3-year-old Cuban girl who lost both legs to gangrene stands for first time with prosthetics

By 

A three-year-old Cuban girl was able to part with her wheelchair and stand up for the first time after losing both her limbs to an illness just months after she was born.

On Monday, the toddler was fitted for temporary prosthetics at the Shriners Hospital for Children in Tampa, Fla.

Her mother, Jaqueline Vidal, told WFLA News that it was “very emotional” seeing her daughter stand for the first time.

“Everybody’s waiting for this moment,” Vidal told a WFLA reporter with the help of a translator. “They’ve been waiting a long time to see her walk.”

Alexa Prieto developed gangrene while she was being treated for intestinal issues at a hospital in Havana when she was only three months old. To save her life, doctors had to amputate both of her legs.

Prieto was sponsored by a Cuban-born orthopedics specialist named Armando Quirantes, who brought her to Florida to be fitted for prosthetics.

The toddler underwent surgery to prepare for the prosthetics last fall, WFLA reported.

Dr. Bryan Sinnott, a senior prosthesis specialist at the Tampa hospital, said Prieto’s prosthetics are clear so that his team can identify problems and make adjustments as the three-year-old becomes familiar with her new set of legs.

Source of the Article: https://globalnews.ca/news/4876820/cuban-girl-gangrene-prosthetics/

 

Researchers demonstrate key to success of nerve transfer technique in bionic reconstruction

Modern prostheses offer patients who have had a hand amputated much greater capability in everyday life than was possible with previous prosthetic reconstructive techniques. Redundant nerves from the amputated extremity can be surgically transferred to provide a much better connection between the patient’s body and the prosthesis. This technique has proven to be successful, although the specific reasons for its success were not fully understood. A team of researchers led by Konstantin Bergmeister and Oskar Aszmann from the Division of Plastic and Reconstructive Surgery and the Christian Doppler Laboratory for Recovery of Limb Function at MedUni Vienna, demonstrated, in an animal model, that the key to success lies in the muscle undergoing a change of identity triggered by the donor nerve.

Bionic prostheses are mentally controlled, in that they register the activation of residual muscles in the limb stump. Theoretically it should be possible for the latest generation prostheses to execute the same number of movements as a healthy human hand. However, the link between man and prosthesis is not yet capable of controlling all mechanically possible functions, because the interface between man and prostheses is limited in terms of signal transmission. “If we could solve this problem, the latest prostheses could actually become an intuitively operated replacement that functions just like a human hand,” underscore the researchers.

To enable the prosthesis to move at all, nerves have to be surgically transferred during the amputation procedure to increase the total number of muscle control signals. This involves connecting amputated peripheral nerves to residual muscles in the amputation stump. This method is very successful, because these muscles regenerate after a few months to provide better control of the prosthesis. However, until now, it was not clear what specific changes this nerve transfer technique produces in muscles and nerves.

Previously unknown neurophysiological effects discovered

As part of an experimental study conducted over several years, a research team led by Konstantin Bergmeister and Oskar Aszmann from MedUni Vienna’s Division of Plastic and Reconstructive Surgery (Head: Christine Radtke) and Christian Doppler Laboratory for Recovery of Limb Function have now shown that this nerve transfer technique has previously unidentified neurophysiological effects. These result in more accurate muscle contractility and much more finely controlled muscle signals than previously thought.

It was also found that muscles take on the identity of the donor nerves, that is to say the function of the muscle from which the nerve was originally harvested. This means that muscles can be modified very specifically to achieve the desired control of the lost extremity. This information will now be used in follow-up studies to refine the surgical technique of nerve transfer and adapt it more accurately to fine control systems. The vision of an intuitively controlled prosthesis that can perform all the natural manual functions could become a reality within the next few years.

Source:

https://www.meduniwien.ac.at/web/en/about-us/news/detailsite/2019/news-im-jaenner-2019/bionic-reconstruction-after-amputation-of-a-hand-muscles-can-be-repurposed-using-nerve-transfers/

Source of Article: https://www.news-medical.net/news/20190107/Researchers-demonstrate-key-to-success-of-nerve-transfer-technique-in-bionic-reconstruction.aspx

3D-printing dad makes bike for children missing limbs

 

Adam Dengel and son ThomasImage copyright ADAM DENGEL                                                                            Adam Dengel was inspired to start helping other children through experiences with his son

A dad who builds 3D-printed arms in his garage workshop has created a specially adapted bicycle for children missing an upper limb.

Adam Dengel, 30, created his first DIY limb in his bedroom for son Thomas, four, who was born without a hand.

He has since set up a charity and made superhero-themed prosthetics free of charge for children around the world.

For his latest project, he plans to surprise four children with their own custom-made bikes.

They cost £220 to make and are fitted with an ergonomic cup which allows the rider to reach the handlebars without leaning.

Mr Dengel said the modification makes the bikes safer to ride than a normal model.

The parts, like the arms, are created on Mr Dengel’s 3D printer in the garage of his home in Royston, Barnsley, which he has converted into a workshop.

“These kids haven’t had the best start in life and we wanted to help boost their confidence,” he said.

“Plus this gets them outside, riding bikes with other youngsters, and helping them to make friends.”

The adapted bikeImage copyright ADAM DENGEL
The design means children with missing upper limbs do not have to lean to reach the handlebars

Mr Dengel, 30 and his wife Katie were inspired to help others through their experiences with their son.

Thomas was born with a short forearm and missing his hand due to amniotic band syndrome – a rare condition where stray bands of tissue wrap around the limbs of an unborn baby and cut off blood flow.

Unhappy with the basic NHS prosthetic, the couple started looking at alternatives and found a charity which made Thomas his first mechanical arm.

This led him to buy his own printer and set about creating a number of colourful, comic book-inspired hands for his son – including his latest Batman-themed prosthetic.

Some of the arms made by Adam DengelImage copyrightADAM DENGEL
Image captionThe bike adaptations and arms are built by 3D printers
Thomas DengelImage copyright ADAM DENGEL
Son Thomas has a selection of superhero arms thanks to his father’s efforts
Presentational white space

Through the couple’s charity LimbBo Foundation, Mr Dengel has so far built 33 personalised arms for children, including youngsters in America and Holland.

“To say we the charity started out as an idea on the sofa we’re thrilled with how things have gone,” he said.

“We only ever wanted to help other kids like Thomas and it gives us so much pleasure to know we’re doing that.”

Source of the article: BBC News

BIOMEDICAL ENGINEERING BRINGING A HUMAN TOUCH TO MODERN PROSTHETICS

‘Electronic skin’ allows user to experience a sense of touch and pain; ‘After many years, I felt my hand, as if a hollow shell got filled with life again,’ amputee volunteer says

Amputees often experience the sensation of a “phantom limb”—a feeling that a missing body part is still there.

That sensory illusion is closer to becoming a reality thanks to a team of engineers at Johns Hopkins University that has created an electronic skin. When layered on top of prosthetic hands, this e-dermis brings back a real sense of touch through the fingertips.

“After many years, I felt my hand, as if a hollow shell got filled with life again,” says the amputee who served as the team’s principal volunteer. (The research protocol used in the study does not allow identification of the amputee volunteers.)

Made of fabric and rubber laced with sensors to mimic nerve endings, e-dermis recreates a sense of touch as well as pain by sensing stimuli and relaying the impulses back to the peripheral nerves.

“We’ve made a sensor that goes over the fingertips of a prosthetic hand and acts like your own skin would,” says Luke Osborn, a graduate student in biomedical engineering. “It’s inspired by what is happening in human biology, with receptors for both touch and pain.

Luke Osborn interacts with prosthetic hand

Image caption:Luke Osborn interacts with a prosthetic hand sporting the e-dermis

IMAGE CREDIT: LARRY CANNER / HOMEWOOD PHOTOGRAPHY

“This is interesting and new,” Osborn adds, “because now we can have a prosthetic hand that is already on the market and fit it with an e-dermis that can tell the wearer whether he or she is picking up something that is round or whether it has sharp points.”

The work, published online in the journal Science Robotics, shows it’s possible to restore a range of natural, touch-based feelings to amputees who use prosthetic limbs. The ability to detect pain could be useful, for instance, not only in prosthetic hands but also in lower limb prostheses, alerting the user to potential damage to the device.

Human skin is made up of a complex network of receptors that relay a variety of sensations to the brain. This network provided a biological template for the research team, which includes members from the Johns Hopkins departments of Biomedical EngineeringElectrical and Computer Engineering, and Neurology, and from the Singapore Institute of Neurotechnology.

VIDEO: AMERICAN ACADEMY FOR THE ADVANCEMENT OF SCIENCE

Bringing a more human touch to modern prosthetic designs is critical, especially when it comes to incorporating the ability to feel pain, Osborn says.

“Pain is, of course, unpleasant, but it’s also an essential, protective sense of touch that is lacking in the prostheses that are currently available to amputees,” he says. “Advances in prosthesis designs and control mechanisms can aid an amputee’s ability to regain lost function, but they often lack meaningful, tactile feedback or perception.”

That’s where the e-dermis comes in, conveying information to the amputee by stimulating peripheral nerves in the arm, making the so-called phantom limb come to life. Inspired by human biology, the e-dermis enables its user to sense a continuous spectrum of tactile perceptions, from light touch to noxious or painful stimulus.

The e-dermis does this by electrically stimulating the amputee’s nerves in a non-invasive way, through the skin, says the paper’s senior author, Nitish Thakor, a professor of biomedical engineering and director of the Biomedical Instrumentation and Neuroengineering Laboratory at Johns Hopkins.

“For the first time, a prosthesis can provide a range of perceptions from fine touch to noxious to an amputee, making it more like a human hand,” says Thakor, co-founder of Infinite Biomedical Technologies, the Baltimore-based company that provided the prosthetic hardware used in the study.

THE TEAM FOCUSED ON DEVELOPING A SYSTEM CAPABLE OF DETECTING OBJECT CURVATURE (FOR TOUCH AND SHAPE PERCEPTION) AND SHARPNESS (FOR PAIN PERCEPTION).

The team created a “neuromorphic model” mimicking the touch and pain receptors of the human nervous system, allowing the e-dermis to electronically encode sensations just as the receptors in the skin would. Tracking brain activity via electroencephalography, or EEG, the team determined that the test subject was able to perceive these sensations in his phantom hand.

The researchers then connected the e-dermis output to the volunteer by using a noninvasive method known as transcutaneous electrical nerve stimulation, or TENS. In a pain-detection task the team determined that the test subject and the prosthesis were able to experience a natural, reflexive reaction to both pain while touching a pointed object and non-pain when touching a round object.

The e-dermis is not sensitive to temperature—for this study, the team focused on detecting object curvature (for touch and shape perception) and sharpness (for pain perception). The e-dermis technology could be used to make robotic systems more human, and it could also be used to expand or extend to astronaut gloves and space suits, Osborn says.

The researchers plan to further develop the technology and work to better understand how to provide meaningful sensory information to amputees in the hopes of making the system ready for widespread patient use.

Johns Hopkins is a pioneer in the field of upper limb dexterous prosthesis. More than a decade ago, the university’s Applied Physics Laboratory led the development of the advanced Modular Prosthetic Limb, which an amputee patient controls with the muscles and nerves that once controlled his or her real arm or hand.

Posted in Science+Technology

Source of article: https://hub.jhu.edu/2018/06/20/e-dermis-prosthetic-sense-of-touch/