When an arm or other extremity is amputated or lost, a prosthetic device, or prosthesis, can play an important role in rehabilitation. For many people, an artificial limb can improve mobility and the ability to manage daily activities, as well as provide the means to stay independent.
Prostheses Parts and Types
There is a wide variety of prostheses that are designed to function — and in many cases look — like a natural arm, leg, hand, or foot. Although there are many different designs, most have similar parts. These include:
A socket into which the stump of the amputated limb fits
The suspension, which holds the prosthesis onto the stump
The foot, hand, or hook
A covering for cosmetic appearances
The socket is often lined with foam or silicone to protect the stump. Special socks are also worn over the stump to ensure a proper fit and improve comfort.
Following are some of the most common types of prostheses:
Lower leg and foot. A number of prosthetic feet are available to simulate the action of a natural foot after an amputation below the knee. At least one available foot-ankle prosthesis is controlled by a microprocessor. It uses feedback from sensors to adjust joint movement, making walking more efficient and reducing the risk of falls.
Leg with knee. For amputations above the knee, the prosthesis has both a knee and ankle joint. Currently there are more than 100 prosthetic ankle, foot, and knee models. Some use fluid or hydraulic-controlled devices that let users vary their walking speed. Others use computerized parts that let the user make rapid real-time adjustments while walking.
Arm and hand. The oldest and most commonly used prosthetic arm is operated with the body’s own movements and a harness that extends in a figure eight across the back and under the opposite arm. Others use a rechargeable battery to run small motors in the prosthetic hand or hook. The battery improves grip strength.
Choosing and Using a Prosthesis
A number of factors are involved in choosing a prosthesis. They include:
The location and level of the amputation
The condition of the remaining limb
Your activity level, particularly for a prosthetic leg or foot
Your specific goals and needs