Test reason and goal: appearances are everything.
It is of ultimate importance to understand that hand amputation as a disfigurement as much as a manual handicap.
Is cosmesis so important?
Disfigurement as such, per se, and in an isolated world of the person that is concerned would not be such a big issue at all. One is disfigured, one gets used to it at least to some degree, and that is that.
If one follows rational thought at all, then:
- We know already - without any visualization - that current attempts to simulate a "life like" appearance all fail totally. Only a few bone hard illusion fans believe just how totally "life like" a, say, iLimb with cosmetic glove is; for these: see below tests and videos.
- Spending money towards a top technology still fails, but that type of goal may set you back by around 35'000 CHF (customized cosmetic but otherwise just passive arm) or a whole lot more (for a "bionic" arm) - and still just fail to really hide the amputee status.
- But not only do serious attempts to simulate human life like appearances fail, worse, they are thought and known to cause a particularly bad effect described by the Uncanny Valley. That model [link1] [link2] tells us that the correlation between life likeness and acceptance is not linear, but complicated.
- We furthermore know from experience and from trial and error that non life-like prosthetic arms can take a lot of stress away, in fact they tend to exceed the top expensive solutions in achieving a better appearance or solution to some aspects of body image issues.
- Body image is body image - and whatever we do there, is up to us. So if I do or do not wear a prosthetic arm is only a part of what all of me is, and what other people see and think is beyond control anyway.
- If prosthetic arms generally have a bad acceptance, then one interpretation certainly is that the industry fails us. And that is certainly a correct interpretation for many reason all of which (at least in theory) can be changed. So as industrial representative, the best angle of attack is to understand what all is wrong with prosthetic arms in order to make better ones first and sell more then. This website is full of tips, clues and rather hard indicators along that direction.
- If prosthetic arms generally have a bad acceptance, another interpretation however is that so and so many amputees cannot be wrong. Given the current prosthetic arm options, not wearing a prosthetic arm also can have great advantages [link1 SHAP rip] [link2 comparison]. These are not unknown or obscure: even though one gets recognized as amputee, prosthetic arms never change that; even though one has diminished function, prosthetic arms may yield somewhat but not drastically improved function or actually provide a greater handicap. The total cost of prosthetic arms includes spent time, finances and discomfort, damaged clothes and damaged objects as well as possibly injured other people (scratches, bangs, etc).
And so all that follows is probably not too rational
But it would be cool to be able to have the perfect apperance. Forget function for a moment. The missing arm part and hand is a communication barrier (unless one waltzes over it). People attach hopes to this aspect. They nowadays believe that if they own a piece of overpriced gadget junk their life improves. So within that realm of perception, let us think aloud.
And advertising can come across as rather progressive (Otto Bock: "The Michelangelo Hand and the Axon-Bus system are milestones on the path to perfection", Touch Bionics: "With the i-limb ultra, your prosthesis looks and moves more like a natural hand than any other powered prosthetic hand"; RSL Steeper: "bebionic3 utilises leading-edge technology and unique, ergonomic features that make it unlike any other hand available. These innovations combine to give the hand unrivaled versatility, functionality and performance").
Conversely, did you ever think of wearing one of these hands, sitting in a meeting, and pouring a glass of water - and despite all cosmetic glove and "bionic" lookalikes, the loud noise would be the dead giveaway of the hand being a prosthetic?
Any feature that gives the prosthetic nature of a hand away would not be considered so "life-like" and thus any such feature should lead to immediate removal of the product from the line-up of prosthetic hands that can be considered "life-like".
Functional grip engineering and everyday usage from functional view point brought us the Becker hand and various hooks. Really difficult things may best be achieved without disabling prostheses [link]. So optimizing grip function gets us nowhere in terms of "life like" prosthetic hand and arm design. So we should abandon grip aspects altogether when starting out from anew.