Helping hands (and feet)

A couple of years ago, Tommaso Lenzi, an assistant professor at the University of Utah, picked up his phone and sent a photo to Hans Georg Näder, the owner of Duderstadt-based Ottobock, one of the world’s largest prosthetics manufacturers. The image showed a sleek, red-and-black metallic leg. Lenzi had spent almost a decade developing the robotic limb; after countless prototypes and trials, his lab in Salt Lake City was finally happy with the design. “A long time before then, Näder had left me his card,” says Lenzi. “I finally texted him and said, ‘I think I’ve got something.’

Using sensors and custom-built, AI-powered controls to anticipate the movements of the body, the Utah Bionic Leg enables above-the-knee amputees to climb stairs, hike and cycle. Though scientists across the globe had devoted countless hours to developing robotic legs, most previous attempts had been too clunky and complicated to be of much practical use. The Utah Bionic Leg is both lighter and stronger than the average human leg. “We were able to achieve a weight and power that had been thought to be impossible,” says Lenzi.

Soon after receiving Lenzi’s message, Ottobock made a big donation to the academic’s lab and signed a contract to start developing the Utah Bionic Leg for mass production. The company had cause to move fast: a transformation is under way in the prosthetics industry, with technology previously considered the stuff of science fiction becoming a reality. Thanks to advances in robotics, machine learning and materials, as well as generous investments from the US military and the European Union, scientists can now build prosthetic limbs that can match, or even outperform, biological ones. These are often called “bionic” – a buzzword that simply means engineering inspired by biology.

There are several mechatronic hands on the market that read muscle activity in the residual limb and, with the help of AI, can translate it into complex hand movements. Paralympians on running blades can now sprint as fast as Olympic athletes on their own legs. At the Massachusetts Institute of Technology, a new lab filled with neurologists and engineers is developing neural implants that allow the user to control a robotic prosthesis directly with their mind.

The field’s inventions can sound like a teenager’s cyborg fantasy (and often that’s how they begin) but there is a real and urgent demand for them. The World Health Organization estimates that as many as 40 million people across the globe require a prosthesis – and the number is growing. Most users today are medical amputees (often as a result of diabetes) and people born with a limb difference. Still, it can seem that the sector hasn’t come far enough since the early days of industrial production, when veterans of the First World War painfully hobbled around on wooden legs. Even in high-income countries, arm amputees are often told to make do with a hook. There is still no widely available prosthesis that makes it possible for above-knee amputees to climb stairs.

“This industry can be very slow-moving when it comes to innovation,” says Costa Rican scientist Jose Gonzalez. “Understandably, people have concerns over safety.” monocle meets Gonzalez at Ottobock’s headquarters in Lower Saxony, where he works as head of research, Germany. With more than 9,500 employees worldwide and a valuation of about $5.8bn (€5.5bn), Ottobock is one of the industry’s giants. Much of its production line is still dedicated to versions of the C-Leg, a hydraulic device that was introduced in the 1990s. “The machine should ideally adapt to the person,” says Gonzalez. “Right now, the person still has to adapt to the machine.”

Gonzalez’s job is to bridge the vast gap between cutting-edge technologies being developed at universities and the devices being put into mass production. He is working with Lenzi to develop the Utah Bionic Leg, alongside dozens of other projects. The aim is to develop something that can be mass-produced to last for years, comes with a genuine benefit to the user and isn’t prohibitively expensive. “Much of what we do will never see the light of day,” he says. “You have to ensure that it’s a win-win for all parties involved.”

Even with a successful product, a complex network of people must work together to bring it to patients. Doctors have to recommend it, insurance companies need to be convinced of its necessity and prospective users must be assured of its safety.

Among the upstart outfits that are aiming to eat into the market share of firms such as Ottobock is Ukrainian start-up Esper. The company was founded in 2019 by Dima Gazda, a medical doctor and hobbyist electrical engineer who was interning at a hospital when he was struck by how unappealing the options available to amputees were. So he set about developing the Esper Hand, a bionic device that can be controlled by the user through sensors and makes use of machine learning. The company that he set up now has 70 employees, with assembly facilities in Kyiv and its headquarters in New York.

Gazda spent years perfecting the design with two mechanical engineers. “The process was meticulous, iterative and not very pleasant,” he says. In contrast to many Hulk-like alternatives, the Esper Hand is almost dainty, with a female and male size. Its considerate details include fingertips that can be used on a touch screen. The hand has also already passed a tough practical test: it has been fitted to dozens of Ukrainian soldiers.

At Esper’s office in Brooklyn, monocle meets Emily Peterson, who is sitting opposite Gazda. Born with a limb difference, Peterson is an avowed fan of the Esper Hand. Like most prosthesis users, she has a custom-made socket (the part that fits to the residual limb) and switches between several artificial hands. She tells monocle that, with the availability of newer prostheses such as the Esper Hand, simply getting through the day with a synthetic limb is no longer the biggest challenge. “The problem now isn’t how to interact physically with the world,” she says. “It is to have the world be comfortable with you.”

Lenzi says that this is where design comes into play. Most common prostheses can be fitted with skin-coloured gloves that are intended to make the device almost indistinguishable from the rest of the body. While the Utah Bionic Leg takes inspiration from the shape of the human calf, ankle and foot, no attempt is made to hide the fact that it is a machine. Lenzi’s team made the deliberate choice to make the leg brightly coloured and futuristic. “Part of the reason why people hide a prosthetic is that they feel that it signals disability – that they are weak,” he says. “But as these technologies come out, there will be a huge shift.”

To illustrate this idea, Lenzi points to a prosthetic that’s so widespread that people rarely think of it as one. “I wear glasses but you wouldn’t say that I’m disabled,” he says. “That’s because lenses work really well and there’s no difference in my ability to participate in society. If you look at the design of glasses, people aren’t trying to hide them. They’re part of their expression.” When it comes to the next generation of prosthetics, the real sign of success will be when wearing one isn’t considered remarkable at all. — L

Back on their feet
While hi-tech prosthetics are trickling into the market, the World Health Organization estimates that, as a result of the lack of access to high-quality healthcare across the globe, only one in 10 people who need a prosthesis have access to even basic assistive products. Swiss-Kenyan venture Circleg is working to address this with a low-cost prosthetic leg that was launched last year. “Most people who need prosthetics either don’t have access to it or can’t afford it,” says co-founder Simon Oschwald. “There is a huge gap between provision and demand that we are working to fill.”

Oschwald and Circleg co-founder Fabian Engel originally developed the prototype for the prosthesis as their bachelor’s thesis in industrial design. The leg is modular, size-customisable and can be assembled locally in Nairobi. It is sold as part of a holistic package that includes orthopaedic training for fitting sockets and starts at as little as $350 (€332) – a fraction of the prices for state-of-the-art prostheses such as Ottobock’s Genium X4, which can run into six figures. After a year in business, Circleg has B2B clients in East and West Africa, and has just expanded to Latin America. “When you lose a leg, the main barrier is that you are seen as disabled and unable to provide for the community,” says Oschwald. “We are trying to shift that perspective.”