Amputation Health Article

Definition

Amputation is the intentional surgical removal of a limb or body part. It is performed to remove diseased tissue or relieve pain.

Purpose

Arms, legs, hands, feet, fingers, and toes can all be amputated. Most amputations involve small body parts such as a finger, rather than an entire limb. More than 60, 000 amputations are performed in the United States each year.

Amputation is performed for the following reasons:

• to remove tissue that no longer has an adequate blood supply
• to remove malignant cancers (almost exclusively in the case of osteogenic sarcoma or other sarcomas)
• as a result of severe trauma to the body part

The blood supply to an extremity can be cut off because of injury to the blood vessel, hardening of the arteries, arterial embolism, impaired circulation as a complication of diabetes mellitus, repeated severe infection that leads to gangrene, severe frostbite, Raynaud's disease, or Buerger's disease.

More than 90% of amputations performed in the United States are due to circulatory complications of diabetes, the most common cause of non-traumatic leg and foot amputations.

Precautions

Amputation cannot be performed on patients with uncontrolled diabetes mellitus, heart failure, or infection, and is also inadvisable for patients with blood clotting disorders.

Description

Amputations can be either planned or emergency procedures. Injury and arterial embolisms are the main reasons for emergency amputations. The operation is performed under regional or general anesthesia by a general or orthopedic surgeon in a hospital operating room.

Details of the operation vary slightly depending on what is to be removed. The goal of all amputations is twofold: to remove diseased tissue so that the wound will heal cleanly, and to construct a stump that will allow the attachment of a prosthesis or artificial replacement part.

The surgeon makes an incision around the part to be amputated. The part is removed, and the bone is smoothed. A flap is constructed of muscle, connective tissue, and skin to cover the raw end of the bone. The flap is then closed over the bone with sutures (surgical stitches) that remain in place for 3 to 4 weeks. Often, a rigid dressing or cast is applied that stays in place for about two weeks.

Preparation

Before an amputation is performed, extensive testing is done to determine the proper level of amputation. The goal of the surgeon is to find the place where healing is most likely to be complete, while allowing the maximum amount of limb to remain for effective rehabilitation.

The greater the blood flow through an area, the more likely healing is to occur. These tests are designed to measure blood flow through the limb. Several or all of the following can be done to help choose the proper level of amputation:

• measurement of blood pressure in different parts of the limb
• Xenon 133 studies, which use a radiopharmaceutical to measure blood flow
• Oxygen tension measurements in which an oxygen electrode is used to measure oxygen pressure under the skin. If the pressure is 0, healing will not occur. If the pressure reads higher than 40ml Hg (40 milliliters of mercury), healing of the area is likely to be satisfactory.
• laser Doppler measurements of the microcirculation of the skin
• skin fluorescent studies that also measure skin micro-circulation
• skin perfusion measurements using a blood pressure cuff and photoelectric detector
• infrared measurements of skin temperature

No one test is highly predictive of healing, but taken together, the results can give the surgeon a detailed idea of the best place to amputate.

Aftercare

After amputation, medication is prescribed for pain, and patients are treated with antibiotics to discourage infection. The stump is moved often to encourage good circulation. Physical therapy and rehabilitation are started as soon after surgery as possible. Studies have shown that there is a positive relationship between early rehabilitation and effective functioning of the stump and prosthesis. Length of stay in the hospital depends on the severity of the amputation and the general health of the amputee, but is usually less than one week.

Recovery from surgery takes about six weeks. Rehabilitation, however, is a long and arduous process, especially for above-the-knee amputees. The doctor and physical therapist decide how soon after surgery the patient can begin to exercise, and several sessions each day may be recommended. In addition, psychological counseling is an important part of rehabilitation. Many patients experience a sense of loss and grief when they lose a body part. Others are bothered by phantom limb syndrome, where they feel as if the amputated part is still in place. They may even feel pain in the limb that has been removed. Many amputees benefit from joining self-help groups and meeting others who are also living with amputation. Addressing the emotional aspects of amputation often speeds the physical rehabilitation process.