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. In some cases, it is carried out on individuals as a preventative surgery for such problems. A special case is the congenital amputation, a congenital disorder, where  foetal limbs have been cut off by constrictive bands. In some countries, amputation of the hands or feet was or is used as a form of punishment for criminals. Amputation has also been used as a tactic in war and acts of terrorism.  In some cultures and religions, minor amputations or mutilations are considered a ritual accomplishment. Unlike many non-mammalian animals, (such as lizards which shed their tails), once removed, human extremities do not grow back. A transplant or a prosthesis are the only options for recovering the loss.

# Overview
The history of human amputation can be divided into a number of periods. Initially the many thousands of years when limb loss was the result of trauma or 'nonsurgical' removal. This was followed by the hesitant beginnings of surgical intervention, mainly on gangrenous limbs or those already terribly damaged, which developed through to surgical amputations around the 15th century, the distinction is marked by the choice of the patient and the aim of saving a life and achieving a healed stump, despite the difficulties with infection and the lack of effective control for pain or blood loss. Improvements in surgical techniques were married with better haemorrhage control in the 19th century and in the 1840s with anaesthesia and around twenty years later efficient infection control. The 20th century noted marked improvements in surgical techniques and also a move to increasingly sophisticated prosthetic limbs.

# History

## Origins of the word
Amputation is derived from the Latin amputare, to cut away, from amb (about) and putare (to prune). The Latin word has never been recorded in a surgical context, being reserved to indicate punishment for criminals. The English word amputation was first applied to surgery in the 17th century, possibly first in Peter Lowe's A discourse of the Whole Art of Chirurgerie (published in either 1597 or 1612), his work was derived from 16th century French texts and early English writers also used the words "extirpation" (16th century French texts tended to use extirper), "disarticulation," and "dismemberment" (from the Old French desmembrer and a more common term before the 17th century for limb loss or removal), or simply "cutting." but by the end of the 17th century amputation had come to dominate as the accepted medical term.

# Types and causes
Types of amputation include:
- leg
amputation of digits
partial foot amputation (Chopart, Lisfranc)
ankle disarticulation (Syme, Pyrogoff)
below-knee amputation (transtibial)
knee-bearing amputation (knee disarticulation)
above knee amputation (transfemoral)
Van-ness rotation (Foot being turned around and reattached to allow the ankle joint to be used as a knee.)
hip disarticulation
hemipelvectomy
- amputation of digits
- partial foot amputation (Chopart, Lisfranc)
- ankle disarticulation (Syme, Pyrogoff)
- below-knee amputation (transtibial)
- knee-bearing amputation (knee disarticulation)
- above knee amputation (transfemoral)
- Van-ness rotation (Foot being turned around and reattached to allow the ankle joint to be used as a knee.)
- hip disarticulation
- hemipelvectomy
- arm
amputation of digits
metacarpal amputation
wrist disarticulation
forearm amputation (transradial)
elbow disarticulation
above-elbow amputation (transhumeral)
shoulder disarticulation and forequarter amputation
Krukenberg procedure
- amputation of digits
- metacarpal amputation
- wrist disarticulation
- forearm amputation (transradial)
- elbow disarticulation
- above-elbow amputation (transhumeral)
- shoulder disarticulation and forequarter amputation
- Krukenberg procedure
- teeth
The avulsion of some teeth (mainly incisives) is or was practiced by some cultures for ritual purposes (for instance in the Iberomaurusian culture of Neolithic North Africa).
- The avulsion of some teeth (mainly incisives) is or was practiced by some cultures for ritual purposes (for instance in the Iberomaurusian culture of Neolithic North Africa).
Hemicorporectomy, or amputation at the waist, is the most radical amputation.
Genital modification and mutilation may involve amputating tissue (as the case is with circumcision), although not necessarily as a result of injury or disease.
As a rule, partial amputations are preferred to preserve joint function, but in oncological surgery, disarticulation is favored.
Reasons for amputation
- Cancerous bone tumours (e.g. osteosarcoma, osteochondroma)
- Severe limb injuries in which the limb cannot be spared or attempts to spare the limb have failed
- Circulation problems
- Deformities of digits and/or limbs
- Any advanced cancers
- Gangrene
- Bone infection (osteomyelitis)
- Traumatic amputation (Amputation occurs actually at scene of accident, the limb can be partially or wholly severed)
- Amputation in utero (Amniotic band)
- Mastectomy (amputation of breast) for breast cancer

# Method
The first step is ligating the supplying artery and vein, to prevent hemorrhage. The muscles are transected, and finally the bone is sawed through with an oscillating saw. Skin and muscle flaps are then transposed over the stump, occasionally with the insertion of elements to attach a prosthesis.

# Self-amputation
In some rare cases when a person has become trapped in a deserted place, with no means of communication or hope of rescue, the victim has amputated his own limb:
- In 2007, 66-year old Al Hill amputated his leg below the knee using his pocketknife after the leg got stuck beneath a felled tree he was cutting in California. 
- 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.
- Also in 2003, 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. 
- In the 1990s, a crab fisherman got his arm caught in the winch during a storm and had to amputate it at the shoulder, as reported in The New Englander.
Even rarer are cases where self-amputation is performed for criminal or political purposes:
- Documentary filmmaker Errol Morris was ordered to "leave town within twenty-four hours or leave in a casket" by the unnamed "king of the nubbies" of the town of Vernon, Florida (which Morris called "Nub City"), when he was researching a documentary about a bizarre scam wherein individuals would cut off their own limbs as a way to collect insurance money.  The final version of Vernon, Florida contains no references to this scam.
- On March 7 1998, Daniel Rudolph, the elder brother of the 1996 Olympics bomber Eric Robert Rudolph, videotaped himself cutting off one of his own hands with an electric saw in order to "send a message to the FBI and the media." 
Body Integrity Identity Disorder is a psychological condition in which an individual feels compelled to remove one or more of their body parts, usually a limb.  In some cases, that individual may take drastic measures to remove the offending appendages, either by causing irreparable damage to the limb so that medical intervention can not save the limb, or by causing the limb to be severed.

# After-effects
A large proportion of amputees (50-80%) 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. Phantom sensations and phantom pain may also occur after the removal of body parts other than the limbs, e.g. after amputation of the breast, extraction of a tooth (phantom tooth pain) or removal of an eye (phantom eye syndrome). A similar phenomenon is unexplained sensation in a body part unrelated to the amputated limb. It has been hypothesized that the portion of the brain responsible for processing stimulation from amputated limbs, being deprived of input, actually expands into the surrounding brain, such that an individual who has had an arm amputated will experience unexplained pressure or movement on their face or head. The individual may also experience some trauma as well as emotional discomfort.
In many cases, the phantom limb aids in adaptation to a prosthesis, as it permits the person to experience proprioception of the prosthetic limb.
Another side-effect can be heterotopic ossification, especially when a bone injury is combined with a head injury. The brain signals the bone to grow instead of scar tissue to form, and nodules and other growth can interfere with prosthetics and sometimes require further operations. This type of injury has been especially common among soldiers wounded by improvised explosive devices in the Iraq war.