Post-traumatic stress

Sometimes, when something bad happens, the feelings from that experience can keep coming back to trouble a person. Strong memories of the bad experience can seem to come out of nowhere.

A normal, everyday sound or sight can trigger the scary memories. Experts call this post-traumatic stress disorder, or PTSD. “Post” means “after.” A trauma is something disturbing that happens to a person, such as a war, an accident or a natural disaster. (Most service members do not have PTSD.)

People with PTSD might have nightmares. If it is bad enough, it can make it hard for people to get along in ordinary life. Normal things like going to the grocery store might trigger bad reactions. It might be hard for them to act normally to people in their lives.

Artificial body parts

Most combat injuries do not cause a service person to lose a limb, such as an arm or leg. But when this does happen, the wounded person is fitted with a prosthesis (pros-THEE-sus).

A prosthesis is an artificial body part. Prostheses can be made to replace anything from a whole leg to an ear or finger.

Building a prosthesis

To figure out the right size and shape of the prosthesis, medical experts might start with a plaster model.

They might also take a digital image of the remaining part, and make a model of that. For example, if a soldier has lost a leg, doctors will take a digital picture of the other leg and use that as a model.