Above the elbow amputations are also called trans-humeral amputations and are more difficult than below the elbow amputations to fit with prostheses that are comfortable and functional. When the injury happens at the level of the elbow or above, the person must have a transhumeral amputation with the attempt made to have the stump as long as possible. Longer stumps can help the individual use the prosthesis more effectively.
Another above the elbow amputation that is more severe is through the shoulder with shoulder disarticulation. These are the hardest to place with a prosthesis that the patient can easily use and tend to be unwieldy and more for aesthetics than for functionality. The more joints that have to be replaced, the harder it is to have a functional prosthetic.
After a single upper limb amputation, the prosthetic device is placed about 1 to 6 months following corrective surgery. It is important to start using a prosthetic device as early as possible so the patient has a chance of finally being able to effectively use the prosthesis. If the prosthesis is placed too late, the chances of a successful patient-prosthetic device relationship goes way down.
The socket of the prosthetic device must fit snugly in the upper arm and have a great deal of connection to the skin. It must be of the utmost comfort or the patient will not be able to use the device. Arm prostheses are different from leg prostheses because they don’t have to bear the full weight of the body. Even so, the socket is made to have pressure relief over the bony areas at the end of the stump, the elbow and the shoulder. A harness is often used to stabilize the prosthesis to the upper extremity. Some prosthetic devices use straps instead. The straps are made from leather and make a figure of eight shape behind the upper back and under the good arm that is holding the prosthesis in place. The harness is also available to hold the mechanical devices that allow the elbow and hand to move.
Mechanical elbows are used in above the elbow amputations. They are usually simple hinges that allow the lower arm to move up and down so as to extend the arm in space or bring an object in the prosthetic hand close to the mouth or to the body. An elbow is able to be bent through the means of a cable connected to the harness. Alternatively the upper arm is activated to allow the elbow to bend. There is usually a locking mechanism that keeps the elbow locked in place so the hand can be used without a floppy elbow.
The “hand” part of the prosthesis can look like a hand. Hands can be extremely bulky and often have less strength than a hook. Hooks are better when the person wants a rugged use for the device and it allows the patient to see the objects that are being manipulated. Manipulation of objects is actually easier with a hook than with an artificial hand.
One study was done on a patient with an above the elbow amputation and brachial plexus lesion. This patient was successfully treated with a hybrid type of prosthesis that included a myoelectric hand. There are many things being done with prostheses these days that make for successful “use” of a traumatically amputated arm.