Taking a prosthesis off and on

A socket is attached to the body on one end and to the prosthesis on the other end. Then the person can put the artificial part on and take it off.

Injured troops may get several different prosthetics for the same injury. This allows them to go back to doing the activities they enjoyed before their injuries.

For example, a soldier who enjoys rock climbing might get a special prosthesis to allow him or her to keep climbing. This would be different than the prosthesis he or she needs to walk to work.

Bionic parts

In the 1970s, two TV shows featured a “bionic man” and a “bionic woman” with superpowers. Bionics (bye-AH-niks) is the science of developing electronic or mechanical parts to replace body parts.

Replacing body parts with powerful artificial parts may seem like science fiction. But it is starting to come true. Some injured U. S. troops are now testing these parts.

Bionic arm

The military is helping to develop a robotic arm. To make this arm work, remaining arm nerves are moved to another part of the body, such as the chest muscles.

A tiny device that reads electric signals is attached inside the prosthetic arm socket. It reads signals from the nerves and chest muscles.

An injured person can just think about opening or closing his or her hand, and the bionic hand will open or close. The hand is so sensitive that the person can pick up a grape without crushing it.

Nothing like this has ever been built before. With other arms, the person needs to think of separate steps to control the hand. For example, he or she might need to make large movements, such as shrugging shoulders or flexing a remaining arm muscle, to get the arm to work. Some prosthetics have hooks at the end.

Bionic knee

One advance is a bionic power knee. A power knee has a tiny computer and motor that helps a person walk and stand up more normally.

The computer is programmed to tell the leg to do what the missing muscles would have done in the past.