Why do people stop using their prosthetic arms? [vicious cycle]
Posted on August 5, 2010
The question is: Why do people stop using their prosthetic arms? This question is relevant as:
- Arm amputees are a rare occurrence, relatively. Due to that, non-disabled people will feel nervous and start by supplementing real dialog with self-constructed ideas. That is the beginning of a usually somewhat bad ending.
- Prosthetic arms seem to be very expensive, probably also as a consequence of that.
- And studies show some 30% of arm amputees not using their prosthetic arm any more; adding to that the people that don’t even participate in these studies any more, an anecdotical observation of around 50% of non-users seems more probable.
So in an underserviced market, companies run up to a rare form to sell cheap electronics for dream prices that further that vicious cycle or death cycle. Isn’t this absolutely remarkable (after all, you read it here first)?
Vicious cycle
Filed Under Prosthesis, Specifications and comparisons | Leave a Comment
V2P Prehensor / PUPP+CH+EN wrist > ADL Activities of Daily Living > The Very Profane > Push Comes To Shove > Cleaning Toilet
Posted on July 22, 2010
What Otto Bock, RSL Steeper or TouchBionics always try to withhold from us are the bare facts of life, the profane tasks. But that’s quite alright, I am sure we can get them up to date somehow.
Filed Under ADA technologies, Brands, Household, PhysioNetics, Prosthesis, Prosthetic hook, Specifications and comparisons, Tricks and techniques, V2P Prehensor | Leave a Comment
Hot summer - beer time [ADL, Becker hands]
Posted on July 18, 2010
Summer time and how to go about beers.
Holding drinks, glasses, cups is an issue for me. Particularly when there is finger food.
The V2P works fine, but when you are at a party, I strongly suggest the Becker hand (out of a collection of Otto Bock hand, Otto Bock hook, Hosmer hooks or V2P). It works reliably (and you don’t want to drop that beer, trust me), elegantly and affordably.
Cheers :)
Product reference: Becker Imperial hand.
Filed Under "Bionic" prostheses, Becker Hand [Lock Grip, Imperial] {mechanical hand}, Becker Hand [Lock Grip, Imperial] {mechanical hand}, Brands, Prosthesis, Specifications and comparisons | Leave a Comment
Prosthetic industry language - amputee/media language - lies, lies, lies!
Posted on April 15, 2010
In prosthetic industry, language is often used in a wrong way. There are exaggerations as far as the eye reaches. Let us have a close look at what these exaggerations are. Secondly, amputees and media often use language in a similarly wrong way. Exaggerations as well.
Why all that drama?
Filed Under Disability and the public, Media, Prosthesis, Specifications and comparisons | Leave a Comment
Learning from industry and industrial design for prosthetic design
Posted on February 13, 2010
I have been saying and living (!) all along that a detailed functional analysis necessarily precedes successful prosthetic design.
It also precedes successful design anywhere else. Apple recently revealed the iPad. But listen to how Steve Jobs explains what they did: they analysed what was wrong with existing solutions and then designed and built their new device to specifically fill that niche. And so those of you that kept trucking by extending the old prosthetic design metaphor (build it from cheap crap, make it look neat and sell it for millions to non-disabled company or insurance representatives): go and study and do a detailed functional analysis first. The deeper and more detailed, the more extensive and unforgiving, the better.
But now let us see what Steve Jobs can teach us about that:
Obviously Steve gets it wrong soon with his iPad evangelizing - my netbook is absolutely great, slow, light, cheap and has a very long battery life, it runs PC software which in fact is great - so it does exactly what I want it to do. No way an iPad would be of help. Besides, Steve and his friends at Apple still violate Telecommunications Act Section 255 so they should have plenty to do until they fixed that mess. But Steve’s means to arrive at that conclusion - by seeing what is not good about existing parts - is the way to do it. That is where I think he completely nailed it.
How do we apply that to prosthetic arms that allow for gripping and holding items, most notably the ones operated by myoelectric switches or cable control?
Filed Under Artwork and Do It yourself Corner, Prosthesis, Prototype development, Specifications and comparisons | Leave a Comment
2010’s “bionic” prostheses and why they fail
Posted on February 8, 2010
We wonder why these very cool looking and beautifully designed “bionic” prostheses [BeBionic, iLimb, Michelangelo] remain cumbersome and why, as products, they just tank.
The mechanism why we must love them is neurological. Our brain is programmed to positively respond to certain triggers. We like shiney objects. We love 3D. And we sure love things that promise both. So it is clear why “boinic” hands are loved by engineers, tinkerers, media and the (non disabled or otherwise disabled) public alike: by virtue of the Mesmerized Bunny Effect.
They do not stand up to promise. And if previous clear indications keep getting ignored, I’ll repeat them here. After all, upper extremity prostheses are rejected by 33% to 38% of those users that do participate in surveys - and that is a lot. Not counting these that are disillusioned and stop participating. That failure rate is so high, in fact, that we see it is an industry failing its clients through small time tinkering and greed, not an industry facing a daunting job.
If these prostheses actually were ‘bionic’, they would not just look like a movie prop. Instead, by being truly bionic, they would:
- Feel ‘bionic’ - that is, painless, seamlessly integrated, worrilessly angulated, stress free in grip control,
- Move ‘bionic’ - prosthetic parts move in a fluid and effortless motion together with existing joints rather than just doing simple grasp/ungrasp motion,
- Degrade and fail ‘bionically’ - that is, fail gracefully and gradually.
But in reality, ‘bionic’ used for such constructions is probably a straight plain lie. It is most likely founded in hyped up overadvertising and not at all in reality as particularly these myoelectric prosthetic arms:
- do not feel seamlessly integrated, worrilessly angulated and stress free in their grip control but quite the contrary: grip control is typically unreliable, elbow motion is heavily and painfully restricted, there is no wrist motion at all at my level of amputation, so the term ‘bionic’ has no bearing here;
- do not move in a fluid and effortless motion together with existing joints and residual extremities but in reality, they produce isolated uncoordinated motion that turn my elbow and shoulder muscles to painful hardwood;
- do not at all fail gracefully and gradually, but are alive one moment, dead next moment, grip hard one moment and let go the next; I never dropped as much stuff as when wearing the myo arm. These are embarassingly unreliable. I much rather go out without prosthesis.
If we look at the materials, make, design, care of build and other details of many commercially available parts, it is mind-bogglingly easy to understand: prosthetic arms are built rather affordably and then sold for huge amounts of money, and getting that money back as a client, or revising any technical decision - as a client - is next to impossible. Once insurance buys that prosthesis, money is gone.
It takes a simple user as me just about a year to figure that out - but so-called specialists have been playing pogo-pogo with the subject for decades. Absent wrist and restricted elbow motion due to a painful and hard to use socket - and then act ’surprised’ that shoulders and back are overused and painful and hard when just touched gently? Obviously that type of outcome is common and in each and every instance it is very bad. Then what? More ‘bionic’ gadgets? Why insurances don’t investigate this is beyond me. Can’t they afford specialists?
Of course, amputees don’t melt or go away. Were you thinking that? Long lasting disappointment is one outcome, another one is to not even showing up for studies no more. Yet another outcome is shoulder overuse due to poor fitting of the prosthetic parts into one’s overall activity, and poor shoulder function is conversely associated with particularly poor prosthetic usage. A recent outcome is that amputees start to network and create their own activity to remedy the lack of cogent care by finding better representatives of support.
No, really we are dealing with an industry that is shooting itself into its own foot. In a major way. And it is necessary to address that in very clear terms.
When I tried my first myoelectric arm, I had a special socket made for testing purposes. It was very painful, I could not lift stuff, the hand was not reliable, the elbow could not be leaned upon. And all it all it was a particularly cumbersome experience so I read up in current medical literature. Also, I was surprised and asked other users.
- A user of > 20 years of experience: “And everything you describe is how it was for me. The elbow was pushed inward to fit tight over my elbow, to help hold the thing on…yeah right! The tiniest bit of sweat and it would slide down and pinch my elbow bones to the point of pain. And so, besides the cost of the thing, that’s why I don’t wear anything anymore.“
- A user of > 50 years of experience: “I have not yet seen any myo that can out perform a body powered unit unless there is no residual limb left to work with. Particularly if it’s bang for my own buck….there is no comparison. Just ask for a reference of a satisfied myo user with similar condition to yours. I’ll bet you don’t get one or if you do it will be disappointing. Also demand a gratis build if you find it too uncomfortable to use. I predict that there will be a lot of shuffling and maybees. 50 + years of experience here and nothing has changed but the costs.“
- Another user: “I have a myo electric arm and the not in control, I am finding out..(..) Just the slightest muscle movement its like the arm goes into a “fit”.”
So, here is why these “bionic” hands tank.
Filed Under "Bionic" prostheses, BeBionic (RSL Steeper), Becker Hand [Lock Grip, Imperial] {mechanical hand}, DEKA arm / DARPA project, Otto Bock Michelangelo hand, Prosthesis, Research, Specifications and comparisons, Touch Bionics iLimb | Leave a Comment
Approximating the Carroll Quantitative Test for Upper Extremity Function comparing hooks [V2P, Dorrance, Otto Bock] and hands [Otto Bock, Becker Lock Grip]
Posted on February 8, 2010
I am not saying that the Carroll quantitative test for upper extremity function is necessarily the test most related to my own Activities of Daily Living (ADL). It is not.
But manufacturers are going above and beyond their call of duty to build “bionic” prostheses that seem to excite their engineers, the media and that by and large miss the point of functional prosthetic support while public money for research is wasted away on similarly useful gadgetry. Can you believe it? With a BeBionic hand you can even grab an apple? How amazing! With the iLimb, you can hold a water bottle! Wild! And the Otto Bock Michelangelo hand can also grab an apple. Oh, well.
So again amputees are mostly on their own as far as the real works are concerned.
On my way trying to get an understanding of the interplay between grip angles and usefulness I am trying to work towards better defining a modern test for relevant dexterity. And for that, it helps to play with a previously established test and then discuss maybe what it does well, what it does not show, and what it can be used for.
Furthermore, current advertising for “bionic” prostheses [Michelangelo, BeBionic, iLimb] usually show activities that any prosthesis can achieve and as such do not prove a particular point.
After reading through Carroll’s paper, I decided to implement the following tasks:
Filed Under ADA technologies, Becker Hand [Lock Grip, Imperial] {mechanical hand}, Becker Hand [Lock Grip, Imperial] {mechanical hand}, Brands, Cable control, Hosmer Dorrance, Movohook 2Grip, Otto Bock, PhysioNetics, Prosthesis, Prosthetic hand, Prosthetic hook, Specifications and comparisons, V2P Prehensor | Leave a Comment
Ultimate in Prosthetic Performance Scoring: The EODF End Of Day Feeling
Posted on January 11, 2010
Don’t worry about any detailed analysis or technical feature, about concise specifications or spring angles. Whatever it is you are wearing or not wearing in terms of prosthetic arms, what ultimately counts is your EODF (End Of Day Feeling).
