Prosthetics and Orthotics

The science of being able to provide an artificial substitute for the limbs is one of the most important around. This is because it deals with parts of the body that are needed for a normal life. Imagine being without a full set of limbs - you won't have that much confidence, would you?

This branch of biomedical engineering is an extremely old one, with records of attempts at it since about 45,000 years ago. It arises from Man's primal ways of war, where injuries often result in amputation (echoes of Star Wars...)

Early prosthetics are just like those in pirate movies - mere stumps for the legs, and hooks for arms. They do, however served to provide some functional use for what was left of the limb. Amputees were able to walk, and manipulate objects, but they often suffered from discomfort.

The big push for development in prosthetics came during the two World Wars. Governments on both sides of the Atlantic found themselves with tens of thousands of amputee veterans. A great wave of sympathy brought about the founding of what is now called the American Orthotics and Prosthetics Association or A.O.P.A.

With that, and advances in technology, prosthetics became more specific to the user, and more comfortable to use. Plastic resin was used to configure legs to individual users, and simple joints and attachments enabled some flexibility and control.

Current technology is based on myoelectric technology, which was developed during the 1970s. It involves using the small impulses from the person's nerves to operate [servos], and enable movement. This way, an amputee is able to operate the arm just as he would with a natural one.

[Myoelectric] arms these days have reaction times that are as fast as the limbs they replace. They also come with synthetic skin, for cosmetic purposes, and temperature and touch sensors, so as to give the user the use of some of his senses.

Current work is being done on myoelectric legs and feet which would allow the user not only to walk, and do a slow jog, but also experience the pressure under the feet as well.

With such rapid advances in technology, it won't be long before myoelectrics and normal limbs become indistinguishable.

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