While the surgery used to be recommended mainly for seniors, since the replacement limbs were expected to last around 10 years, advances in materials and technique have brought new mobility to younger and younger patients. Artificial limbs have been around for ages-think of pirates depicted with hook hands or peg legs. But today's prostheses are far more advanced. Many can use the minute amounts of electricity generated in the body's muscles to direct battery-powered artificial arms and legs. An artificial hand, for example, can be directed to open or close.
Some hands have sensors to detect temperature.
Artificial feet can be designed to bend and spring like real feet do. And some can help the wearer know whether their weight is on their heels, toes or the sides of their feet, aiding in balance. Your heart's valves open and close to control the direction of blood flow within the heart. When your doctor listens to your heartbeat, he or she is listening to the valves open and close. If the valves don't work correctly, the blood won't flow through the heart properly.