Body Talk [user perspective/s with regard to "bionic" hands]

In a recent article1, points were made that resonated relatively highly inside the amputee community2. That is because the author, Britt H. Young, authentically describes experiences we all made in various ways.

What can be learned from this, though?

  • Comfort and fit including getting weight / center of gravity right is a key, and an absolute requirement [link​]. The more distal the center of gravity, the more dire the consequences for skin, comfort, socket wiggle and friction rash [link, link].
  • Grip access and grip function are absolute requirements (see about grip angles and grip surfaces: link). They cannot just be approximated and then you hope for the best - as a designer, if you do not absolutely obsess over these, you won't get it right, you just won't.
  • A person has to be equipped with a prosthesis so it really helps them. For that, the intra-person comparison, the "intra-person" or "within one/same person" comparison or even "competition", if you will, is the only relevant comparison: what can a given / same / one person do better (A) as is - without prosthesis on, (B) with prosthetic setup 1, (C), with prosthetic setup 2, et cetera, and, then, what has to happen that performance (B|C|...) is better than performance (A). It is of more or less no concern, how competitions between prosthetic setups (B|C|..) among different people turn out unless it helps you to understand that myoelectric "bionic" hands are junk so therefore, the body-powered split hook wins [link].
  • Overuse in light of repetitive or hard work is a reality. This article does not mention this aspect with a single word. Either the author is privileged to not perform any hard / real work that is able to cause overuse problems or problems in context of asymmetry, or she is going to experience that later. If you are interested about this, read about hazardous real work [link], and explanation of overuse [link]. As researchers seem to think that a single extreme compensatory motion is as bad as doing these all the time, and as they seem to be unable to grasp the effects of heavy hazardous work on the prosthetic hand and their user vice versa single acts of, say, flipping newspaper page, another attempt at explanation was made [link].
  • The principle of a build and the build itself are two different things, so start with the better principle [link]. The principle of a body-powered arm has potential to be used to build a really good prosthetic arm, whereas the principle of a myoelectric arm does not nearly have as much potential to begin with [link]. Reality has it, that prosthetic technicians and prosthetic component manufacturers feed off insurances mostly, and routinely avoid customer contact [i.e., link]. The mail correspondence that I have with the "customer service" of Ossur, Otto Bock or Touch Bionics are a real and total turn-off, not a bit discouraging but something I see as outright offensive - they take absolute top dollar, and then, that? So the chances that even the little potential that a myoelectric arm may havegets anywhere is something I see as very low on a scale of 1 to 10. The chances they build particularly useful parts for body-powered arms, given what clearly seems to be their attitude and technical understanding [link, link, etc.], is also low on a scale of 1 to 10 in my current personal estimation. So really they seem to be going nowhere. This must be the jist of things, the attitude, development and technical proficiency that seems to justify articles such as above.
  • Be aware of snake oil salesmen. Read the history of the Carnes arm, and read it thoroughly and all of it: the manufacturer also made attempts to overstate is performance while a critical review by Sauerbruch apparently was ignored3. Right now, "bionic" arms in fact are in major downfall as they fail on all ends. Even a "sturdy" terminal device does not make up for uncomfortable sockets and unreliable control. Be careful and ask others before wasting more than you can easily afford to lose.

Footnotes

  1. https://www.inputmag.com/culture/cyborg-chic-bionic-prosthetic-arm-sucks:

    Body talk - by Britt H Young - (C) Copyright Inputmag / Britt H Young

    I have one of the most advanced prosthetic arms in the world — and I hate it

    Being a cyborg is cool right now, thanks in large part to gee-whiz media coverage. But actually using a bionic arm can really suck.

    Lately, I have been thinking about getting a new arm. With the profusion of lower-cost and 3D-printed prosthetic arms on the market, I’ve been hoping to finally find one that fits well.

    While shopping online, I land on the site of one of the dozens of new, high-tech prosthetic arm companies and pulled up some of their videos to get a closer look at socket designs. Instead, I get yet another example of what I call “prosthetic unboxing videos” so popular on TikTok and local news stations alike.

    These videos are a cliché by now: young kids with missing limbs wiggling with joy as they unbox and put on a new prosthetic arm for the first time. In 2015, Robert Downey Jr. himself presented a then seven-year-old boy with a 3D-printed Iron Man–styled prosthetic arm.

    These videos never show prosthesis users doing two-handed tasks. Instead, they do things most of them would only ever undertake with their other fleshy hand, like write or drink water. These videos, for the most part, exist to emotionally move the non-disabled viewer (that’s what we in the community call “disability porn,” folks).

    Don’t get me wrong — I have been psyched about a new arm, too! But the media’s coverage of these new kinds of prosthetics is so focused on the initial joy or incredulity — on the idea that “lives are changed” — that they forget to ask if these hands are actually useful and what happens in the weeks and months after the unboxing.

    Because every upper-limb amputee (acquired or congenital) has a unique body, their experiences with prostheses and the prosthetists who provide them vary dramatically, making user experience especially difficult to study. Upper-limb prosthesis user dissatisfaction is generally very high, with the majority of users in one recent study reporting very negative experiences. Recent studies report rejection rates — those at which people discontinue using their prostheses entirely — as high as 44 percent.

    The average percentage is likely even higher among children because they more often will lose patience while learning how to control prostheses and experience greater discomfort with the weight. Even as prostheses have advanced to the point of becoming points of fascination on TikTok and the Forbes website, user satisfaction has largely stagnated in recent decades. Still, it should be noted that the rate of satisfaction of users of this new wave of prosthetic arms hasn’t yet been the subject of a large-scale study.

    In the meantime, we are inundated with clickbait tear-jerkers like “11-year-old flexes his new bionic arm.” If the endless media hype is to be believed, you’d assume high-tech prosthetic arms are turning people into superhumans. “People expect you as a cyborg to be able to punch through walls,” says Londoner Ashley Young, who has tested a smattering of the latest multi-articulating hands (prostheses with independently moving fingers).

    I was born without most of my left forearm; prosthetists call me “short” because my limb stops almost immediately past my elbow. I was first fitted with a prosthesis at six months old, and I’ve been shoving my arm — ahem, “residual limb” — into a socket almost ever since. At that time in the early 1990s, doctors were telling the parents of limb-different kids that we should be fitted with prostheses as early as possible so that our brains would develop “normal” hand-eye coordination. I wore a simple, single-grip myoelectric for most of my childhood. It was bulky and had an extremely tight socket I had to force my “little arm” into using Aveeno hand cream. It gripped poorly and would sometimes glitch in the middle of class.

    Eventually, I decided the weight and lack of functionality wasn’t worth it and switched to using a “passive,” or lifelike arm without any powered components. That is until 2018, when I was wowed by news reports about the Bebionic, the flagship model of powered hand from German company Ottobock. It has multi-articulating fingers, numerous grip modes, and is small enough to not look like the wearer has a Hulk fist. The news made it seem impossibly cool. After seeking out a new prosthetist, I got my first powered hand in over 15 years.

    When my new, 21st-century arm arrived, I hosted an “arm party,” an absurdist celebration of the new device as well as a farewell for a pile of old, passive arms with broken silicone fingers held on with Band-Aids. We had cocktails with arm puns: Armageddon, Pink Armadillo. And we played prosthetic arm Twister during which you could use any of the old prosthetic arms in the pile to help you reach. We got high and set up a makeshift photo booth with a bedsheet so everyone could take surreal pictures with way too many arms.

    It was the first time in my life my arms were fun and the basis for shared hilarity, not just me being weird. At the end of the night, the Bebionic — with me attached — cut the celebratory chocolate cake.

    And that was one of the last times I ever used it.

    Maybe it was because it felt heavy as hell. It was only three pounds or so, but three pounds feels like a ton to a limb that typically carries no weight, and the heft of the prosthetic hand pulled hard on the socket and made me sweat. In order to open and close, myoelectric hands require that you flex your muscles where sensors inside of the socket can detect your movement. There are typically only two “contact site” sensors inside the socket — this is called a “dual-site” system — so you need to cycle through a series of grip patterns by flexing twice in quick succession inside of the socket to get to the one you want.

    The “power grip” (a fist) is cool, but, oh my God, trying to cycle through all the modes to find it is infuriating. (Did I mention that you cannot reprogram the hand to include more grip patterns without an appointment with your prosthetist?) In fact, everything about the Bebionic was exhausting. I’ve used it on and off on special days, but most often as a party trick: Wanna see me crush a can?

    Maybe I just realized that very few things in life truly require two “fleshy” hands to get them done, and that my new fancy hand still couldn’t compete with my own lifelong adaptations. Yet, there were some days I’d try it out for as many hours as I could. Overall, I found integrating it into daily movements actually surprisingly easy. I had spent my whole life watching two-handed people do fancy things like close a door with one hand and lock it with the other. Finally, I could do that too (though I was unable to pull off that mesmerizing dance of knife and fork that my steak-cutting friends are able to do). I was also able to hold a plate with one hand and snack and gesticulate with the other at a New Year’s Party once.

    You know the only other time I could do these things? When I am not wearing any prosthesis at all.

    Prosthetic arm technology is still so limited that I become more disabled when I wear one. There are very few, special tasks I can do better with it (case in point: using a potato ricer). But mostly what it does is helps me mimic two-handed people. I realized that my excitement about my new hand was mostly about being able to be something other than disabled — a cyborg. The day my prosthesis arrived, I tweeted a brief video of myself petting my cat with it, the hand’s rubber-lined fingers and palm snagging uncomfortably on the cat’s fur.

    I was in the club now. The self-identified cyborg community is super-chic, all over the internet, and actually celebrated by the media, unlike the regular old disabled community. When did this happen?

    Prosthetic arms and legs were long supposed to help you blend in with the four-limbed crowd and look normal. Then a shift occurred. In the wake of the war on terror and the countless American soldiers coming home with traumatic amputations, the U.S. government launched the Revolutionizing Prosthetics program in 2006 to develop a “neurally controlled artificial limb.” The U.K. also began to invest in similar prosthetic arm moonshots, and private companies soon took up the race to develop the first multi-articulating hand.

    In the last decade or so, the visibility of high-tech prosthetic limbs has exploded, particularly in pop culture. Furiosa in Mad Max: Fury Road has a somewhat ramshackle but still futuristic-cool mechanical appendage. Captain America: Winter’s Soldier features such a capable cybernetic arm that it might as well just be a fleshy hand. The South African mining villain in Black Panther boasts a life-like prosthetic hand with a built-in sonic cannon. The upcoming Mortal Kombat reboot features a character with fearsome metal arms.

    Meanwhile, Vogue has profiled models and fashionistas with cyber-chic prosthetic legs (always legs though, never arms — a story for another day). Today, both amputees and “congenitals” like me want prostheses that look robotic, that call out for attention. Cyborgs are having a moment.

    Take, for example, Angel Giuffria, the cyborg actress whose credits include the 2019 indie film Synthesis and appearances in The Accountant (2016) and The Hunger Games (2014). She pops up on the front page of Reddit regularly. The cyborg identity has launched her internet stardom and has set herself apart in an industry that’s deeply discriminatory against people with disabilities. Angel says her multi-articulating, LED-lit, carbon fiber-coated hand is an extension of herself. She wears it outside of her house so that she knows she can do anything “the way” she wants to do it.

    Often, that’s the way that allows her to be left alone. “If I’m at a restaurant and want to cut a steak, and I go to do it with my little arm, everyone’s gonna stare at me or offer to help,” she tells Input. “But if I do it with my prosthesis, nobody. Says. Anything.” Or, she adds, people will think it’s cool. Angel loves her customized bionic hand and what it enables her to do socially, even if she is able to do most tasks without it. (She did leave me with a weird tip: don’t go to Walmart wearing your bionic arm — for some reason people love to stop you to tell you how much they love your prosthesis there.)

    There’s some truth to poet and disability activist Jillian Weise’s argument in her essay "Common Cyborg" that the nondisabled “like us best with bionic arms and legs…. They want us shiny and metallic and in their image.” Cyborgism often serves as a way to make other people comfortable.

    The media narrative, says James Young — husband of Ashley and a cyborg himself — is designed to be reassuring to people: If you happen to, God forbid, lose your arm, “they” can replace it. “People want to make sure that the technology is out there that can remake you as you are right now,” he says.

    James knows the typical media narrative all too well. After a horrific 2012 train accident left him missing his left arm up to his shoulder and part of his left leg, the video game maker Konami built him a completely custom Metal Gear Solid–inspired bionic arm that was “loaded with extras” like Wi-Fi capability and a detachable drone. The coverage of this project was the perfect encapsulation of the media’s obsession with the nexus of high-tech and heart-warming. Sample feelgood headline: “A bionic limb lifts a life.”

    He says that all the “inspiring” stories of 3D-printed prosthetic hands have misplaced enthusiasm: “It’s going to break as soon as they walk into a wall on accident.” Even James’ sci-fi futuristic arm was bulky, difficult to put on, and quickly broke because its primary function was to look impressive. The prosthetics team substituted some components with bike parts as they rushed to complete the arm for a TV documentary. But it’s not just one-off promotional prosthetic arms that are limited by futuristic aesthetic expectations.

    Even the most expensive and sophisticated prosthetic hands on the market today are still limited by their set of preprogrammed grips that mimic the function of a human hand. Ashley, who has part of her arm like I do, shares the feeling that prostheses can be more debilitating than enabling. And while both Ashley and James agree that it’s cool being a cyborg, these hands still struggle to provide the functionality of older, body-powered prehensors or “claws.”

    These days, James largely uses the Ottobock Greifer, a kind of electric prehensor, which helps him do everyday chores — once he’s completed the cumbersome task of strapping the prosthesis to his torso. Since James was amputated at the shoulder, fit and control are the biggest hurdles. He tells Input that where there’s a real reason to get excited is in innovation in myoelectric control. There are new sensors and new technology able to record and learn multiple “contact sites” on your limb that can correspond to far more complex controls than “open” and “close.”

    Such innovations are desperately needed. Some advocacy groups have suggested that the high rates of dissatisfaction with bionic limbs are primarily the result of the inadequacy of “dual-site” myoelectric sensor systems. But the media has little enthusiasm for the type of innovation that doesn’t focus on the way the bionic arm looks. “It’s hard to really communicate how fantastic something is without the visual aspect,” says James. Everyone wants to see the cool robot hand, but they don’t give much thought to the 16 complex sensors inside.

    Meanwhile, what the mainstream bionic hand discourse leaves out is access. Myoelectric arms start at around $30,000, and most insurance policies will not cover them. Thanks to my extremely generous graduate student insurance, I paid $13,000 for my prosthetic arm, which was originally billed at $72,000.

    For Alexis Hillard, the creator of the YouTube channel “Stump Kitchen,” the obsession with cyborgs is “continuing to drive that wedge between disenfranchised disabled people and those with money and power, creating a new ‘desirable disabled person.’” It seems that the majority of cyborgs out there are white and have some level of class privilege. In the U.S., which lacks universal healthcare, so many people don’t even have the choice to become cyborgs due to the prohibitive cost of prostheses.

    Even if for most people myoelectric arms end up being more flash than function, that flash can improve mental health. Bilateral amputees and those amputated closer to their shoulders, especially, need the opportunity to try any new technology that comes their way. Every disabled person should have the opportunity to at least try these technologies, see how they might work for them, and discover something new about their bodies and their abilities.

    “People have such rigid ideas about the human body.”

    No matter what, being cyborgs isn’t saving us. The most disabling thing about missing my left arm is the way the world treats me, regardless of whether I put on a prosthesis for the day. “People have such rigid ideas about the human body,” says Sara Hendren, Professor at Olin College of Engineering and author of What Can a Body Do? “People wouldn’t make such a huge deal out of disability if they saw their own bodies as getting and receiving help when they need it.”

    In other words, none of us is utterly independent; we are constantly receiving help from other people or from some tool or piece of technology. If more people saw this clearly, then prosthetic limbs wouldn’t be turned into “savior” devices by the media. My choice over whether to be a cyborg or not wouldn’t be so high stakes.

    And when my prosthetic arm sucks — which it does — it would be just as cool to do things my way.

    Maybe I won’t get a new arm after all.

  2. Paraphrased / reworded and anonymized social media posts, regarding this article:

     

     

    User 1: This article is great. When I read it, I thought the same thing. I like my own prosthetic arm now, a Taska hand and Coapt control system. It has the best functionality of any prosthesis I have had so far. The weight of the prosthesis has not changed and it is still a problem to squish my stump into the socket. I hated my prosthesis when I was a child, and my father pushed me to wear it. When I was at school, I would put the prosthesis into my locker. Then, I did not wear a prosthetic arm for over 30 years. I now wear the prosthesis whenever I want, and I take if off when I feel like I just want to be my true self.

    User 2: I hated the Coapt. I could never get it to pair to my arm. But instead of engineers trying to think outside the box, to try other approaches, maybe to stumble across a more accurate system, they keep riding the same dead horse with this. Do not understand me the wrong way though. I am very happy to be a part of this roboticized arm world, and I am very lucky. But things are not advancing fast enough in my view. That drives me mad!

    User 1: Did you get the Coapt generation 1? Generation 1 was not as good for me as generation 2, which I love. Generation 2 of the Coapt system is so much easier to use. The Taska hand is much better to use than the Bebionic. I cannot believe however how heavy they still are.

    User 2: Maybe I have Coap generation 1. It has been a few years, since I obtained that setup, it contained a Bebionic 3 hadn and a Boston elbow. Even now that I have an Infinite Bio (IBT) control system, the control is not that accurate. For as heavy as they are, they should not break as easy as they do.

    User 1: I had the Coapt generation 1 system, until about a year ago. I was frustrated considerably, but I was not dissatisfied with generation 2. I am not trying to convince you, but for me, Coapt generation 2 was a consideraby better experience.

    User 2: That is all fine. You have to find out whatever it is that works for you. All of these control system have their problems and issues. If the remaining nerves in the stump are too close together after amputation, or if there is nerve damage, so there are no signals at all, no myoelectric system will work for you. So probably, computer brain interfaces (CBI) are the way to go. They take the nerves out of the equation. The CBI uses signals directly from the brain. The current CBI options are invasive, whereas sensors are directly implanted into the brain, but they will be coming up with noninvasive surface electrode systems. This will be great!

    User 1: I am all for non-invasive systems!

    -----------------

    User 3: I have an i-Limb, and the weight of it alone is a big problem for me. The sweat and the i-Limb's limited function add to my frustration.

    User 4: I understand and empathize. I have an i-Limb "Quantum". A device of that heavy weight and that expensive price makes you think it could crush a diamond. However, it cannot even crush a tin can. That performance aspect is a great disappointment.

    User 5: I also had an i-Limb. It weighed heavily, and that was a problem for me as it was hanging off my shoulder with no stump. I understand totally what you are saying there.

    User 2: Yes, I a not negative about this - I am only telling how it is, I am only being realistic.

    User 1: Yes, you are.

    User 6: It takes training and time to get good at using the device. The opinions I read here seem to be rather negative for new people trying these devices out. I have used my Bebionic hand on my myoelectric arm for 17 years now. There are false claims in the report that has been posted above - I can select grip patterns myself, with the software, and I do not need to go to the prosthetic technician every time for that. I find that the Bebionic hand greatly helps having a positive impact on my psyche. Wearing it, I have the perception of being "whole" again. However, the workhorse that I use for heavy equipment and tools is my body=powered arm.

    User 5: Do not understand my criticism the wrong way. I do love my robotic arm, and I regard having it as a privilege. But it only offers a facade, the only cool thing about it are its looks. There are a lot of severe issues that need to be urgently addressed, such as the extremely high price, the severely inaccurate control system, the heavy weight and associated issues. Also, what do doctors have to do with prescribing a prosthetic arm to an amputee that has fully healed up? I do not need a doctor's prescription to buy a phone, or a car? The system is broken as well.

    User 7: You are right. Also price wise, the i-Limb costs about 80000 USD here, whereas my almost new car was around 30000 USD.

    User 5: It would be good if someone would listen. The researchers and developers should think more out of the box. Due to the price, we cannot get a "decent" prosthetic arm anywhere. And honestly, I do not want to be "Ms. Hook".

     

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    User 8: The article "Body Talk" is very interesting to read. It seems from that article, that it takes a lot of hard work to get used to using a "bionic" arm to one's own advantage. It seems to be a lot easier to just suck it up and live life as is, after an arm amputation, without the hassles of such a "bionic" arm. That alone, without the added drama, seems to take long enough. I am just being practical with my opinion as an amputee, not negative.

    User 2: I had posted the article "Body Talk" above particularly for the engineers. They can easily get a lot of grant monet by showing tear-jerker articles about some kid unboxing some 3D-printed arm. The fields of robotics is severely lacking in comparison to some fields that are leading technology, like electronics. Also, we need to make technology available to everyone. It does not matter if we have to design the prosthesis ourselves or if we have to find someone that will read the article and listen.

  3. See LINK: "Mr. Smith acts as an acrobat or juggler when he presents the Carnes arm. After producing manual demonstrations for fifteen minutes his heart rate was 140 beats per minute, and he sweated profusely. Also I noted that you (the gentlemen of the ) had missed the fact that his stumps were covered with sores and eczema. Mr. Smith asked me about these as he said he frequently could not use and move the prostheses as the stumps were painful."

Cite this article:
Wolf Schweitzer: Technical Below Elbow Amputee Issues - Body Talk [user perspective/s with regard to "bionic" hands]; published 10/03/2021, 10:47; URL: https://www.swisswuff.ch/tech/?p=11615.

BibTeX: @MISC{schweitzer_wolf_1620623746, author = {Wolf Schweitzer}, title = {{Technical Below Elbow Amputee Issues - Body Talk [user perspective/s with regard to "bionic" hands]}}, month = {March},year = {2021}, url = {https://www.swisswuff.ch/tech/?p=11615}}