-bionics (baɪˈɒnɪks) n (functioning as singular)
- (Computer Science) the study of certain biological functions, esp those relating to the brain, that are applicable to the development of electronic equipment, such as computer hardware, designed to operate in a similar manner.
- (Surgery) the technique of replacing a limb or body part by an artificial limb or part that is electronically or mechanically powered
Once only the stuff of science fiction, bionics have come to life and brought with them the hope of revolutionizing artificial limbs. Bionics is of particular interest to upper extremity amputees because replacing the fine dexterity of a hand is very difficult.
While the materials used to build artificial limbs have changed vastly, the designs have changed little. Until 1964, upper extremity prostheses were body powered- the movements of the elbow and terminal device were generated by a system of harnesses, cables, and the patient's own movement. In 1964, the first myoelectric arms were developed, which produce the movements of the hand and elbow with less harnessing and cables by using muscle contractions as trigger signals. However, as muscles atrophy over time it becomes harder to detect the muscle contractions.
Bionics takes a different approach, instead of using muscle contractions as the stimulus for hand and elbow movement, bionics harness the nerve impulses to produce very intuitive and responsive movements.
First, surgical reinnervation is performed, where a surgeon relocates an amputee’s nerves inside the residual limb so that the terminal ends are inside muscles. This is not the traditional method of amputation, but it could become more common as bionics are used more frequently.
When the nerves heal, they are able to fire and the muscles act as biological amplifiers, producing a bigger, easy to detect signal. The reason why this is such a breakthrough, is that patients don’t have to consciously contract their muscles to produce movements in their arm and hand, they can simply think about moving them. This is what makes them neuroprosthetics.
As if that weren’t cool enough, now bionics are being used to produce sensations as well. By stimulating those same nerves with sensors on the robotic hand, amputees are able to feel with their prosthesis. When they touch something they can feel if it is rough, like sandpaper, or smooth like glass.
Bionics are already used commonly in other healthcare fields; cochlear implants to help the deaf hear, and ventriculoperitoneal shunts to alleviate excessive cranial pressure in those with hydrocephaly.
While bionic limbs are currently still in the earliest stages of testing and the use of them requires surgery, big steps are being taken towards making bionics the new gold standard for prosthetic care.
I have listed links to some articles and videos about bionics below. Enjoy!