Cosmetic arms aren’t as non-functional as you believe

The key issue for this article are these:

• People frequently associate ‘cosmetic’ or ‘passive’ arms with ‘no action.
• People frequently associate ‘myoelectric arms’ with most action and function.
• Whereas body powered arms are associated with outdated functionality that is considered crude.

Comparison of activities

Over a  few hundred single actions were noted and evaluated performed by a total of 121 study participants [1].

Stabilisation and support, hold, balance

Actually functional (AF) prostheses were used to perform an average of 16,8 stabilizing actions compared with a number of 13,1 stabilizing manipulations using cosmetic (C) arms. Support actions amounted to 1,9 (AF) versus 1,7 (C) actions – practically similar results.

Holding actions were performed 0,2 times (AF) and – with the cosmetic arms – twice as often, 0,4 times (C). Use of prosthesis as balancing tool was done 0,75 times (AF) versus 1,62 times (C), almost twice as much.

In real life, I use the cosmetic arm in a more reliable fashion than the functional prosthetic parts of the body powered arm to carry a food tray, for example. A metal hook provides less of a reliable support for carrying a tray than a flat rubbery and very sturdy silicone covered hand. To balance objects, a cosmetic arm provides a most reliable tool and to call that non-functional ignores the daily requirements for balancing, holding or stabilization.

Push

Pushing is used to switch lights off and on, to turn a radio or vacuum cleaner off or on. Push buttons are the most frequent target of my push actions, other than typing on a keyboard.

An average of 4,3 (AF) versus 2,7 (C) actions were noted in this study. With that, the usual cosmetic hand may be a bit softer than mine – and I do find that the harder the terminal device, the easier and more inviting is it to use it for precision push operations.

My favorite prosthetic part to wear for typing is a metal hook, followed by a gripper hook equipped with a pencil for better keyboard operation, followed by the cosmetic arm (which happens to be light as well as follow motion very precisely).

Other actions

Without surprise, absent manipulation options – grip, release, pull – are not done using cosmetic arms and hence cannot be compared. But due to absent manipulation functions, cosmetic arms are a lot more durable, break less often, last longer, and are a lot lighter in weight than so-called actively functional prostheses. Due to that I can wear a cosmetic arm for a lot longer than I can wear an actively functional arm.

[1] An evaluation of the use made of cosmetic and functional prostheses by unilateral upper limb amputees. C. M. Fraser. Prosthetics and Orthotics International 1998 22:3, 216-223 — Read More: http://informahealthcare.com/action/showCitFormats?doi=10.3109%2F03093649809164486 [local] (C) Prosthet Orthot Int

 

@article{fraser1998,

author = {Fraser, C. M.},

title = {An evaluation of the use made of cosmetic and functional prostheses by unilateral upper limb amputees},

journal = {Prosthetics and Orthotics International},

volume = {22},

number = {3},

pages = {216-223},

year = {1998},

doi = {10.3109/03093649809164486},

URL = {http://informahealthcare.com/doi/abs/10.3109/03093649809164486},

eprint = {http://informahealthcare.com/doi/pdf/10.3109/03093649809164486}

}