Surgical Procedures/Amputation

Amputation is the removal of a body extremity by trauma or surgery. As a surgical measure, it is used to control pain or a disease process in the affected limb, such as malignancy or gangrene. Amputation is a blind and final method in surgery to save the patient's life.

Types
Types of amputation include:
 * leg
 * amputation of digits(Ray)
 * partial foot amputation (transmetatarsal)
 * ankle disarticulation (Syme)
 * below-knee amputation (transtibial)
 * knee-bearing amputation
 * above knee amputation (transfemoral)
 * hip disarticulation
 * arm
 * amputation of digits(Ray)
 * metacarpal amputation
 * wrist disarticulation
 * forearm amputation (transradial)
 * elbow disarticulation
 * above-elbow amputation (transhumeral)
 * shoulder disarticulation and forequarter amputation

Hemicorporectomy is the most radical amputation. Genital modification and mutilation often involves amputating tissue, although it is usually not a result of injury or disease.

As a rule, amputations through the bone diaphysis are preferred to preserve joint function, but in oncological surgery, disarticulation is favored. (Edited by Dr. Avadh Sahi)

Epidemiology
110,000 a year in the USA ; of those 100,000 are lower limb amputations for peripheral arterial occlusive disease.

Method
A tourniquet is used in orthopaedics to limit bleeding but not in vascular surgery (where the limb is already under perfused because of arterial disease). The muscles are transected, any bleeding vessel is ligated and finally the bone is sawed through. Skin and muscle flaps are then transposed over the stump, except in amputations for gangrene when the stump is left open and allowed to heal by secondary intention.

Complications
Some amputees experience the phenomenon of phantom limbs; they feel body parts that are no longer there. These limbs can itch, ache, and feel as if they are moving. Some scientists believe it has to do with a kind of neural map that the brain has of the body, which sends information to the rest of the brain about limbs regardless of their existence.

Autoamputation
In some rare cases when a person has become trapped (on account of getting a limb stuck) in a deserted place, with no means of communication or hope of rescue, the victim has amputated his own limb: In 2003, 27-year old Aron Ralston amputated his forearm using his pocketknife and breaking and tearing the two bones, after the arm got stuck under a boulder when hiking in Utah. A month later, an Australian coal miner amputated his own arm with a Stanley knife after it became trapped when the front-end loader he was driving overturned three kilometers underground.