When performing an amputation, a surgeon removes a limb, or part of a limb, that is no longer useful to you and is causing you great pain, or threatens your health because of extensive infection. Most commonly, a surgeon must perform this procedure on your toe, foot, leg, or arm. Physicians as well as patients consider amputation a last resort.

Although amputations may be required for other reasons, such as severe injury or the presence of a tumor, the most common reason you may need an amputation is if you have peripheral arterial disease (PAD) due to atherosclerosis (hardening of the arteries). In PAD, the blood vessels in your limbs become damaged because of hardening of the arteries or diabetes. Your body's cells depend on a constant supply of oxygen and nutrients delivered to them by your blood. If your blood vessels are unable to supply blood and oxygen to your fingers or toes, the cells and tissues die and are vulnerable to infection.  If the blood supply cannot be improved sufficiently or if the tissue is beyond salvage, extensive tissue death may require amputation, especially if you are experiencing severe pain or infection.

Most people who require an amputation have PAD, a traumatic injury, or cancer.

PAD is the leading cause of amputation in people age 50 and older, and accounts for up to 90 percent of amputations overall. Normally, surgeons treat advanced PAD through other methods, like controlling infection using antibiotics and draining or removing any infected tissue as well as performing surgery or other procedures to increase the blood flow to the affected area. However, if these treatments do not work, or if the tissue damage is too far advanced initially, amputation will remove a source of major infection and may be necessary to save your life.

A traumatic injury, such as a car accident or a severe burn, can also destroy blood vessels and cause tissue death. As a result, infection if not adequately treated, can spread through your body and threaten your life. Your medical team will make every effort to save your limb by surgically replacing or repairing your damaged blood vessels or using donor tissue. However, if these measures do not work, amputation can save your life. Traumatic injuries are the most common reason for amputations in people younger than age 50.

To perform an amputation, your physician must remove your diseased limb but preserve as much healthy skin, blood vessel, and nerve tissue as possible.

Choosing the incision site is important. If your surgeon removes too little tissue, your wound will not heal because unhealthy tissue remains and the circulation at that level may not be sufficient for healing. To determine how much tissue to remove, before the operation your physician will check for a pulse at a level close to the site. He or she will also compare the skin temperatures in the diseased limb with those in a healthy limb, and note places where the skin appears red, since an incision made through reddish skin may be less likely to heal. Your physician will also check that your skin around the proposed incision point still has sensitivity to touch. Finally, during the operation after he or she makes the initial cut, your physician may decide that more of your limb needs to be removed if the edges of your skin do not bleed enough to allow them to heal.

Before the procedure begins, your anesthesiologist will either put you to sleep with a general anesthetic, or numb your body in the region of the amputation using a regional anesthetic. You will be connected to machines that monitor your heart rate, blood pressure, temperature, and brain function. When the anesthetic has taken effect and you are not able to feel any pain, your surgeon then makes an incision into your skin, leaving enough healthy skin to cover your stump for better healing.

When your surgeon divides the muscles, he or she may shape them, to make sure that your stump has a comfortable contour for your artificial limb. Your surgeon also divides and protects your nerves, so that they are not exposed and painful.

During your surgery, clamps are applied to the healthy major blood vessels to minimize bleeding. Before finishing your amputation, your surgeon will stitch the vessels, and then release the clamps to ensure that all bleeding points are secure.

If you have a traumatic injury, your surgeon will remove the crushed bone and other tissue, a process called "debridement." Your surgeon then will smooth the uneven areas of your bone to prevent pain once you receive your artificial limb. If necessary, your surgical team may then install temporary drains that will drain blood and other fluids that may accumulate.

When your surgeon has removed the dead tissue, he or she may decide to leave the site open (open flap amputation) or to close the skin flaps (closed amputation). In an open flap amputation, your skin remains drawn back from the amputation site for several days so your surgical care team can clean off of any questionable or infected tissue. Once the stump tissue is clean and free of infection, the skin flaps are sewn together to close the wound, a procedure called delayed closure. In a closed amputation, the wound is sewn shut immediately. A closed amputation is usually done if your surgeon is reasonably certain that the chance of infection is small and healing is likely.

Your surgical care team may place a stocking over your stump to hold drainage tubes and wound dressings, or your limb may be placed in traction, or a splint, depending upon your particular situation.