Using a Prosthetic Device

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 shaft.
• 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 100prosthetic 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.

Prostheses are designed and fitted by a specialist called a prosthetist. The fitting process typically begins in the hospital shortly after amputation. It involves:

• Measuring the stump as well as the healthy opposite limb.
• Making a plaster mold.
• Fashioning the socket.
• Attaching the shaft.
• Aligning the prosthesis.

Depending on your comfort and how well your wound is healing, you may begin to practice with your artificial limb as early as 10 to 14 days after surgery. A physical or occupational therapist will train you on how to use and care for it.