If a part (or more parts) of upper extremities are missing, absent function can be replaced to a small degree.
Replacing at least some basic aspects of a hand's function with the rest of the body and immediate environment is what upper extremity amputees including myself do every day.
There are a few questions along the road, but other than that, "manualization of the rest of the body" as well as manualization of surrounding environment is what is going on. There are simply no other options and interestingly, problems are similarly in nature regardless of the type of solution one chooses.
When evaluating a prosthetic hand, when doing evaluation of a prosthetic arm or hook, when evaluating myoelectric or ""bionic"" prostheses such as iLimb, BeBionic or Michelangelo by Otto Bock, then this should be considered thoroughly.
Using no prosthetic arm
Activities of Daily Living - ADL - are typically well handled without a prosthetic arm. Remember, I write this as a one-sided below elbow amputee - and this might or might not be the case for other levels of upper extremity limb loss. But you came here actively and by yourself, this blog is called "below elbow amputee issues", and as that it is heavily biased.
As that I can assure you there is absolutely no problem to run errands, cook meals, fill bottles of water, use the cell phone, assemble very heavy furniture, carry items, drive my car legally, and many other things.
Not only that: some activities such as some sports, driving, playing games or operating a cell phone, getting dressed actually work quite a bit better without a prosthetic arm.
And there are good reasons for that.
- First of all, regular skin is a great surface to work with, grip-wise. That means a stump has the surface of choice whereas any other surface is less useful.
- Secondly, if at all it gets injured or damaged, I can feel most of it while it happens and I can actively minimize damage. That minimizes time that I spend organizing and waiting for repairs. And it reduces cost for insurance or for myself.
- Thirdly, it heals by itself, at least if injuries are mild and superficial. So, damages mostly fix themselves without lots of costs.
- Fourthly, I will not just try to replace the missing hand function and manualize the combination of stump and object or other body part. This includes combinations such as stump/chest, stump/belly, and also stump/furniture, mouth, mouth and hand, stump/table, thigh/thigh, hand (the non disabled one)/foot, hand/feet, foot/foot. I use technical solutions for devices or tools such as scissors, knives, power drills, vices and clamps. In addition, I will find socks, sleeves and stump covers that can provide protection or slippage prevention.
- Five, my stump is extremely fast, sleek and easy to move. While that appears to be a no-brainer, it constitutes a relevant contrast once one talks about prosthetic arms that do not exhibit speed, sleekness, or easiness to move in just the same way.
- And six - my stump is not the greatest functional feature that I have, admitted, but the few things it does it can do very, very reliably. Carrying a tray, driving, carrying a basket - it may not be a lot to you, but when I can drive reliably, or carry groceries reliably rather than dropping them all the time, that is a big thing for me.
So in one word - not wearing a prosthetic does not the slightest bit mean that I will not solve manual tasks. It is often alleged that only a prosthetic can solve such tasks. In my experience that is not the case.
When I do not wear a prosthetic arm, on one hand (broom ting), the disability is visible quite a bit. But then, it is so self explanatory that no time and energy is wasted with that subject. There is no added weight that could stress out my elbow and shoulders, there are no swap or replacement equipment to carry, no special cleaning equipment to carry and use, no time to maintain and clean equipment is spent and no time is spent in the offices of the prosthetic technician, at doctors or elsewhere. Given the frequency and hassle of always taking time out, added over 2-3 years or so, that weighs greatly.
The downside is that I tend to forget that my missing arm is actually relatively short - and I extend my stump to match my other side with the effect of serious asymmetry.
Another aspect is that I will get some skin problems - burns, frost bite, cuts, abrasions, bruises, eczema from chemicals, infections as well as insect bites are all a reality, howevermuch they heal all by themselves.
A third aspect is that for most heavy duty grips - buckets, heavy packages or containers, bags, tools or objects such as vacuum cleaner, computers, .. I will have to use my (left) hand and that may not be good because of chronic overuse.
If I add all of that up, the added drama of not wearing a prosthetic arm at all is near zero except repetitive or heavy duty works. Or working on a computer keyboard for a really long time, maybe.
And that is a great achievement as such. It is worthwhile pursuing. And for heavy duty works, a tight and narrow well fitted socket and a body powered arm with a hook is always the best. So the combination of "no prosthetic" and "body powered / hook" does cover it quite well.
Using a passive arm
In terms of daily tasks, the passive arm is great. It is not so much more equipment than no prosthetic arm that it causes significant restraint or adds heat.
The main mechanism of function is that its soft silicone surface is a useful object to enact the same hand-against-object grip that I outlined above.
So, I manualize my chest, belly, thighs, as well as nearby objects, to jam, fix, squeeze or hold stuff. No problem to use toothpaste and toothbrush, no problem to make coffee.
But I also manualize my stump - at least to a certain extent. It does not appear as stump any more, but it is turned into an interface to the prosthetic arm's silicone liner. With that, a range of advantages and disadvantages come along - most notably, the prosthetic socket compresses my stump and reduces tissue congestion, it hides the stump and provides protection from stares, it physically protects the stump from bangs and hits, cuts and cold or hot temperature, and it introduces the risk of skin problems.
My passive arm is, however, in the way of certain activities, in particular, driving. Luckily there is absolutely nothing faster than removing or replacing a passive prosthetic arm as below elbow amputee. It's a ~ 10 second act.
These prostheses can get damaged and break, and may need to get fixed.
Restoring visible limb presence and correct anatomical length to me is a really relevant aspect of prosthetic arms. I wear my passive arm just because it reminds me that I actually should be whole, and not extend elbow and shoulder of my damaged arm any further. In order to spend a day symmetric and with a balanced shoulder or spine, I should wear any prosthetic arm.
Using a body powered arm
By wearing a body powered arm, I can establish grip function not available with options outlined above.
For that, manualization contains stump, right elbow and shoulder, but as there is a shoulder harness, also my left shoulder. All of these are strained, used asymmetrically, compressed, and may cause interface problems.
The advantage is that I may miss a hand but I can have a grip function. If training, usage, prosthetic build and make, robustness and components allow I can use the body powered arm for heavy objects, for strong grips and for hard work. While that may not be necessarily good for the stump it may not hurt it - and it definitely has the capacity to take a load off my remaining hand.
These prostheses can be built to be relatively robust but may need repairs every now and then.
The mode of control is naturally powered and therefore always available. The mode of control can be graded as finely as the user manages to deliver force graduation. With the right components, grip control can be both strong and finely graded.
Conversely, manualization of my own body as counterpart to hold items does not work THAT well as when holding stuff with my stump or cosmetic (silicone) arm. For that, my prosthetic socket is too hard and too slippery. A sticky surface cover for the socket could be manufactured to provide a workaround.
Using a conventional myoelectric arm
A myoelectric arm is heavy and overuses the body's residual limb and attached joints. Stump muscles are used if not overused to actuate the electrode connected circuitry, and motors as well as batteries represent significant cargo to be carried in addition. As these parts are far from reliable, added drama slows me down all the time.
As stump muscles are used as triggers to control the myoelectric device, their isolated activation may not be intuitive. So manualization also contains an artifical access to using this type of device.
With that, manualization consists mainly in significant added weight and stump muscle overuse or use, as well as skin interface problems and control issues.
With my arm, my myoelectric prosthesis's munster socket would pull on my humeral condyles and cause profuse areas of bruising and subsequent pain. This also is part of manualization of the stump. With overused stump muscles and skin hemorrhages from a tight hard munster socket, my phantom pains soared - all part of 'manualization' of my stump, doing it 'myo-style'.
"Bionic" hands may win social rank games and be quite cute, without question, but there is always a price.
Using brain control for myoelectric arm
If a myoelectric arm will be brain controlled, more power sources - think 'car battery' - may have to be carried as cargo, and not only residual limb and attached joints are manualized but also the head. A current research hand that delivers such function weighs around 7 kg, so you gotta manualize also your back and legs.
This means the same as above but a lot more in terms of loading - extended skin covering of the head introduces eczema, acne, lichen, infections and all the other niceties well known from stump interfaces also to your head.
If you are cool with that, super cool.
I just figured people never considered the manualization concept that I find relevant to understand what upper extremity amputees - conceptually - do no matter what: manualize other areas and surfaces, body parts and objects.
Whatever solution that I choose, problems are eerily similar.
1) Functional problems. If you drop an object, you lose. While I have no apparent grip without prosthesis, I will emulate gripping with the stump in ways that are useful. Sensitivity as well as skin healing are great assets and I do hold and fix objects as you surely understood by now (if not, go up, read that again). The full time service-free availability makes my stump a really useful anatomical part, at least, a lot more useful than meets the eye. Any prosthetic arm introduces some added risk of failure, if not a clear 100% failure to begin with, which makes it unfavorable for driving and moderately favorable for lots of other tasks. If lossy function is acceptable, then prostheses can be a great add-on. The one that offers greatest function is the one with the most versatile grips, highest reliability and based on overall cost and availability structures that the industry has set up, body powered arms offer the greatest choice, by far. Myoelectric arms are a lot less functional due to that - far more expensive, terminal devices are out of reach, frail devices need more and hugely more expensive repairs, devices are inherently far less reliable and cumbersome, and so overall availability and functionality is not that good. While the "bionic" promise is there, we still wait for that to cash in functionally.
2) Skin and interface problems. Whatever is manualized will eventually get damaged - if I press items against my shirt using my stump, the shirt may get dirty or damaged, and my skin may get superficially injured in the process. If I wear a prosthetic arm, the stump may suffer from being underneath a liner. A body powered arm's shoulder harness may cause nerve compression. A heavy myoelectric arm may cause shoulder and elbow overuse. A munster socket of a myoelectric arm may damage the elbow's skin. A head cap worn for brain controlled arms may end up causing scalp problems. If I use a prosthetic arm, it will also constitute an interface of sorts and get used up in that process, incurring more costs and hardware damage (that won't just heal by itself).
3) Cost. A damaged stump skin may require creams, surgical bandages, consulting a doctor or no remedy at all. Damaged prostheses incur costs, where passive and body powered arms usually are somewhat reasonable to fix, whereas myoelectric arms cost a fortune and are ridden with ridiculous warranty regulations no one that I know of can positively comply with.
Overall, prosthetic solutions are viewed within that grid of evaluation. You cannot escape the 'manualization' concept which then slingshots you into a heavily constrained close-tie of connected problems. Brain control doesn't change that at all, just adds other ways to get damaged and waste time and energy.