As Verne understood it, the American Civil War (during which60,000 amputationsaccomplished) ushered in the era of the modern prosthetic in the United States, thanks to government funding and a wave of design patents filed by enterprising prosthetists. Both world wars solidified the for-profit prosthetics industry in the United States and Western Europe, and the current War on Terror helped catapult it to a disastrous stage.$6 billionindustry worldwide. However, this recent reversal is not the result of a disproportionate number of amputations in military conflicts: about1,500 American soldiersj300 british soldiersMembers lost in Iraq and Afghanistan. The loss of limbs in the general population dwarfs these numbers. In the United States alone, more than 2 million people are living with limb loss and 185,000 people are amputated each year. A much smaller subset, between 1,500 and 4,500 children each year, are born with missing or dissimilar limbs, including me.
Today, people who design prosthetics tend to be well-meaning engineers, not amputees. The fleshy stumps of the world act as repositories for these designers' dreams of a superhuman, high-tech future. I know this because I have been presented with some of the best in my entire life.state-of-the-art prosthetic devicesin the market. After being born without a left forearm, I was one of the first cohorts of babies in the United States to receive a myoelectric prosthetic hand, an electronic device controlled by the user's muscles that squeeze against sensors in the prosthetic socket. Since then I have created a variety of prosthetic hands, each striving for the perfect fidelity of the human hand, sometimes at the expense of aesthetics, sometimes at the expense of functionality, but always designed to mimic and replace what is lacking.
Over my lifetime, myoelectric hands have evolved from claw-like designs to anatomically accurate, programmable, multi-grip facsimiles of the human hand, most often costing tens of thousands of dollars. Reporters can't get enough of these nifty, multi-gripped "bionic" hands with realistic silicone skins and organic movements, with the unspoken promise that the disability will soon disappear and any missing limbs or organs will be replaced with an equally capable replica. Innovations in hand prostheses are seen as a top-notch competition to see what is technologically possible. Tyler Hayes, CEO of the prosthetics startupatomic tips, put it like this in aSponsor videowhich helped raise $7.2 million from investors: "Every trip to the moon in history has started with its fair share of insanity, from electricity to space travel, and Atom Limbs is no different."
We are in an arms race for bionic hands. But are we really making progress? It's time to ask who prosthetics are really for and what we hope they will bring. Each new multi-grip bionic hand tends to be more sophisticated, but also more expensive than the last and less likely (even partially) covered by insurance. And, as recent research shows, much simpler and much cheaper prostheses can perform many tasks just as well, and elegant bionic hands, with all their electronic options, are rarely used for gripping.
Activity arms, like this one from the prosthetic company Arm Dynamics, are cheaper and more durable than bionic prosthetics. The accessory from prosthetic manufacturer Texas Assistive Devices is designed to handle very heavy weights, allowing the author to perform exercises that would be risky or impossible with her much more expensive bionic baby arm.Gabriela Hasbun; makeup: Maria Nguyen for MAC Cosmetics; Hair: Joan Laqui for Living Proof
function or form
In recent decades, the overwhelming focus of research and development of new artificial hands has been the refinement of different types of grips. Many of the more expensive hands on the market differ in the number and variety of grip options you can choose from. My personal media favorite, the bebionic Ottobock I received in 2018, has a fist-shaped power grip, pincer grips, and a very specific thumb-over-index mode for politely handing over a card. My 21st century myoelectric hand seemed remarkable until I tried using it for some routine tasks, where it turned out to beMostclumsy and sluggish like you just left him on the couch. For example, I couldn't use it to close a door, which I can do with my stump. And you couldn't pour oatmeal from a pot into a bowl without the extremely expensive addition of an electric cart. to finish taskscool bionic form, although I imitated having two hands, it was obviously no better than doing things my way, sometimes with the help of my legs and feet.
When I first spokepromotional pins, professor of robotics and machine learning at Imperial College London, it was late at night in his office, but he was still animated by robotic hands, the current focus of his research. According to Spiers, from the reality of today's prosthetics to the fantasy of science fiction and anime, the anthropomorphic robotic hand is inevitable. "In one of my first talks here, I showed clips from movies and cartoons and showed how cool filmmakers make robotic hands look," says Spiers. "In the animeGundam, there are so many close-ups of giant robotic hands reaching for things like huge guns. But why does it have to be a human hand? Why doesn't the robot have a gun for a hand?
It's time to ask who prosthetics are really for and what we hope they will bring.
Spiers believes that prosthetic designers are very much concerned with form over function. But he's spoken to enough of them to know they don't share his point of view: "I get the feeling that people love the idea that people are nice and that hands make them unique." developing robotic hand. "This is what the future looks like," he says, looking a little annoyed. "But there are often better ways."
The vast majority of people who wear prostheses are unilateral amputees (people with amputations that affect only one side of the body) and almost always use their dominant "fleshy" hand for delicate tasks like lifting a glass. Unilateral and bilateral amputees also get help from their torso, feet, and other objects in their environment; tasks are rarely performed by a prosthesis alone. However, common clinical assessments to determine the success of a prosthesis are based on using the prosthesis alone, without assistance from other parts of the body. Such reviews seem designed to demonstrate what the prosthetic hand can do, rather than how useful it actually is in its user's daily life. Persons with disabilities are not yet the arbiters of prosthetic standards; we are not yet at the center of design.
Originally designed in the 1920s, the Hosmer Hook [left] is the terminal device still used today in a body energy project. A hammer attachment [right] can be more effective than a claw attachment when driving nails into wood.Links: John Prieto/The Denver Post/Getty Images; Fontes: Sammlung Hulton-Deutsch/Corbis/Getty Images
prosthetics in the real world
To find out how prosthetic wearers live with their devices,Spiers conducted a studywhich used head-mounted cameras to record the daily actions of eight people with unilateral amputations or congenital limb differences. The study,published last year in IEEE Transactions on Medical Robotics and Bionics, comprised various types of myoelectric hands, as well as body-actuated systems that use shoulder, chest, and arm movements transmitted via a wire to mechanically actuate a clamp on the end of a prosthesis. The research was conducted when Spiers was a research associate at Yale University.GRAB-Work, lead byAaron-Dollar. In addition to Dollar, he worked closely with graduate student Jillian Cochran, who co-authored the study.
Looking at the raw images from the study, I felt both sadness and camaraderie with the anonymous denture wearers. The clips show the clumsiness, misjudgments and unintentional falls that are common to even the most experienced prosthetic hand users. Often, the prosthesis simply helps to hold an object against the body to manipulate it with the other hand. It was also evident how much time people spent preparing their myoelectric prostheses for a task: it often took a few extra seconds to manually or electronically rotate their device's wrists, align the object for the proper grip, and close the grip to resolve. Focus. The contestant, who hung a bottle of disinfectant spray from his hand hook while cleaning the kitchen counter, seemed to be the one who figured it all out.
In the study, prostheses were only used in an average of 19% of all recorded manipulations. In general, prostheses were used primarily in non-grasping actions, with the other 'intact' hand doing most of the grabbing. The study highlighted large differences in use between those with body-operated non-electric prostheses and those with myoelectric prostheses. For users of body-operated prostheses whose amputation was below the elbow, nearly 80 percent of prosthetic use consisted of non-grip movements: pushing, pushing, pulling, hanging, and stabilizing. For myoelectric users, the device was used to seize only 40% of the time.
Most telling is that users with non-electric forceps or counter hooks spend significantly less time performing tasks than users with more complex prostheses. Spiers and his team noted the fluidity and speed with which the former performed tasks at home. They were able to use their artificial hands almost immediately and even experienced direct haptic feedback through the cable that powered the systems. The research also found little difference in usage between the single-grip myoelectric devices and the more sophisticated multi-jointed myoelectric hands, except that users tended to avoid objects dangling from their multi-grip hands, apparently for fear of breaking them. . . .
"We felt that people with multi-grip myoelectric hands were reluctant to use them," says Spiers. No wonder, as most myoelectric hands cost upwards of $20,000, are rarely approved by insurance, often require professional assistance to change grip patterns and other settings, and repair processes are expensive and time-consuming. As prosthetic technologies become more complex and proprietary, long-term usability is a growing concern. Ideally, the user should be able to easily repair the device. And yet, some new prosthetics companies are introducing a subscription model where users continue to pay for access to repairs and support.
Despite his study's findings, Spiers says the vast majority of prosthetic research and development is focused on refining the grips of expensive, high-tech bionic hands. In addition to prostheses, manipulation studies in non-human primate research and robotics are primarily concerned with prehension: "Anything that doesn't grab is just thrown away."
TRS manufactures a wide range of body-operated prosthetic accessories for a variety of hobbies and sports. Each accessory specializes in a specific task and can be easily exchanged for a variety of activities.Fillauer TRS
stay with the story
If we decide that what makes us human are our hands and that what makes the hand unique is its gripping ability, then the only prosthetic model we have is the one that attaches to most people's wrists. . However, finding the maximum five-digit comprehension is not necessarily the next logical step. In fact, history suggests that humans have not always been obsessed with perfectly reproducing the human hand.
As reported in the 2001 essay collectionManuscript: Memory and Knowledge in Early Modern Europe, Ideas about the hand have evolved over the centuries. “The soul is like the hand; for the hand is the instrument of instruments," wrote Aristotle inby anima. He argued that mankind was intentionally endowed with a nimble, tangible hand because only our extraordinarily intelligent brains could use it, not as a mere utensil, but as a tool toarrest prison, or "conquering" the world, literally and figuratively.
More than 1,000 years later, Aristotle's ideas resonated with Renaissance artists and thinkers. For Leonardo da Vinci, the hand was the conduit from the brain to the world, and he went to great lengths in his dissections and illustrations of the human hand to understand its major components. His meticulous studies of the tendons and muscles of the forearm and hand led him to conclude that "although human ingenuity makes various inventions... "nothing is lacking and nothing is superfluous."
Da Vinci's illustrations sparked a wave of interest in human anatomy. However, for all the careful interpretation of the human hand by European masters, the hand came to be seen as inspiration rather than an object to be replicated by mere mortals. Indeed, the complexities of the human hand were widely believed to be evidence of divine design. No machine, declared Christian philosopher William Paley, is "more artificial or more patently artificial" than hand flexors, suggesting a conscious design of God.
Performing tasks bionicly, even by mimicking two hands, was no better than doing things my own way, sometimes with the help of my legs and feet.
In the mid-17th century, with the Industrial Revolution in the Global North, a more mechanistic view of the world began to emerge, and the line between living beings and machines began to blur. In his 2003 article “18th century wetware“Jessica Riskin, professor of history at Stanford University, writes, "The period between the 1730s and 1790s was a period of simulation, when mechanics seriously tried to bridge the gap between animated and man-made machines." During this period there were significant changes in the design of the prosthesis. Whereas mechanical prostheses of the 16th century were burdened with iron and springs, a body-powered prosthesis of 1732 used a system of rollers to bend a hand made of light copper. By the end of the 18th century, metal was being replaced by leather, parchment and cork, softer materials that mimicked the fabric of life.
The techno-optimism of the early 20th century sparked another shift in prosthetic design, he says.Lobo Schweitzer, forensic pathologist at the Zurich Institute of Forensic Medicine and Amputees. He has a wide range of modern arm prostheses and has the experience to test them. He points out that anatomically correct prosthetic hands have been carved and forged for nearly 2,000 years. And yet, he says, the 20th-century body-operated spreader hook is "more modern," its design more prepared to break the shape of the human hand.
"In its symbolism, the arm moved by the body (still) expresses the man-machine symbolism of an industrial society of the 1920s."Schweitzer writes about prosthetic arms on his blog, "when man would work like a cog on production lines or in agriculture". In the original design of the Hosmer hook from the 1920s, one loop was placed inside the hook just for tying shoes and another just for holding cigarettes. These designs, Ad Spiers told me, are “incredibly functional, function over form. Every piece had a specific purpose.”
Schweitzer believes that as the need for manual labor declined in the 20th century, functional but non-naturalistic prosthetics were eclipsed by a new high-tech vision of the future: "bionic" hands. In 2006, the US Defense Advanced Research Projects Agency was establishedrevolutionize dentures, a research initiative to develop the next generation of prosthetic arms with "near natural" control. The $100 million program produced two multi-joint prosthetic arms (one for research and one that cost over $50,000). Most importantly, it influenced the development of other similar prostheses and established the bionic hand, such as theI imagine military– like the Holy Grail in prosthetics. Today, the multigrip bionic hand is hegemonic, symbolizing the totality of the cyborg.
And yet, some prosthetic developers take a different view. Headquartered in Boulder, Colorado, TRS is one of the few manufacturers ofjob-specific prosthetic accessories, which are often more durable and less expensive than robotic prostheses. These plastic and silicone accessories, including a soft mushroom device for pushups, a ratchet armband for weightlifting, and a concave swim fin, helped me experience the most functionality I've ever received from a prosthetic arm. .
These low-tech activity prostheses and body-powered prosthetics work incredibly well and cost a fraction of the cost of bionic hands. They don't look or act like human hands and work much better for that. According to Schweitzer, they are prostheses activated by the bodyfired regularlynicknamed "arcane" or ironically "Captain Hook" by engineers. The bionic shoulders and elbows of the future could make a huge difference in the lives of people who have lost a limb up to the shoulder, as long as these devices can be made robust and affordable. But for Schweitzer and a large percentage of users dissatisfied with their myoelectric prostheses, the prosthetics industry still has something fundamentally better or cheaper to offer than body-powered prostheses.
The progress we want
Bionic Hands strives to make people with disabilities "whole" so that we can participate in a culturally two-handed world. But being able to live the life we want with access to the tools we need is more important than looking like everyone else. While many people from various limbs have used bionic hands to interact with the world and express themselves, the centuries-long effort to perfect the bionic hand rarely focuses on our lived experiences and what we choose to do with our lives.
We have been promised a breakthrough in prosthetic technology for nearly 100 years. I remember the scientific enthusiasm for lab-grown meat that feels like explosive change and a sign of intellectual capitulation, neglecting political and cultural change in favor of a technological solution. With the players of the prosthetics world - doctors, insurance companies, engineers, prosthetists and the military - playing the same roles they've played for decades, it's almost impossible to create something truly revolutionary.
Now this metaphorical race to the moon is a mission that has forgotten its original purpose: to help people with disabilities acquire and use the tools they want. Currently, there are affordable low-tech, low-cost prostheses that require investment in innovation to further reduce costs and improve functionality. And, at least in the United States, there is an insurance system that is broken and in need of repair. Freeing us from the arms race of bionic hands could open the door to more functional, more useful and accessible designs, and could help us bring our prosthetic ambitions back to reality.
This article will appear in the October 2022 print issue.
From the articles on your website
- Creating a tactile prosthetic hand - IEEE Spectrum ›
- Building a Super Tough Robotic Hand - IEEE Spectrum ›
- Bionic hand gives amputees sense of touch - IEEE Spectrum ›
- Should the right of repair be extended to bionic body parts? -IEEE... ›
- What Robotics Experts Think About Tesla's Optimus Robot ›