Amputation

Amputation is the removal of a limb or another body part.

This process can occur through physical trauma, medical illness, or surgical intervention. In a medical setting, surgeons perform amputations to control pain or stop a disease from spreading. For example, it may be used to treat malignancy, which is another word for cancer. It is also used to manage gangrene, a condition where body tissue dies. In some rare cases, surgery is performed as a preventive measure to stop future health problems. There is also a unique condition called congenital amputation. This occurs when fetal limbs are cut off by constrictive bands while still in the womb.

When a surgeon performs an amputation, they follow a precise sequence of steps. First, they must ligate the supplying artery and vein. To ligate means to tie these vessels off to prevent hemorrhage, which is heavy bleeding. Next, the surgeon performs a transection of the muscles, meaning they cut through the muscle tissue. The bone is then cut using an oscillating saw. After the bone is severed, the surgeon must file down any sharp or rough edges. Finally, they transpose skin and muscle flaps over the remaining part of the limb, known as the stump.

To improve how the stump functions, surgeons may use myodesis. This is a technique where the muscle is attached directly to the bone or its periosteum, the membrane covering the bone. This helps prevent atrophy, which is the wasting away of muscle tissue.

Amputations are categorized by which part of the body is affected. Lower limb amputations are divided into minor and major types. Minor amputations generally involve the removal of digits, such as fingers or toes. Major amputations include trans-tibial amputations, which occur between the knee and the ankle. These are often called below-knee amputations. Other major types include trans-femoral amputations, or above-knee amputations, and hip disarticulations, where the limb is removed at the hip joint.

There are also specific partial foot amputations like the Chopart or Lisfranc procedures. Some advanced techniques, such as rotationplasty, involve turning the foot around and reattaching it so the ankle joint can act like a knee.

Upper extremity amputations follow a similar pattern of classification. These include partial hand amputations and wrist disarticulations. Common arm amputations include trans-radial procedures, which are below-elbow amputations, and trans-humeral procedures, which are above-elbow amputations. Some specialized methods exist, such as the Krukenberg procedure. In this version of a trans-radial amputation, the radius and ulna bones are used to create a stump that can perform a pincer action. Amputations can also affect the face, involving the removal of ears, the nose (rhinotomy), the tongue (glossectomy), or the eyes (enucleation).

Human history shows that amputation has been practiced for thousands of years. The oldest evidence was discovered in the Liang Tebo cave in East Kalimantan, Indonesian Borneo. A skeleton found there suggests an amputation was performed on a young child at least 31,000 years ago. Throughout history, amputation has also been used as a legal punishment. In 1779, Thomas Jefferson proposed a bill in the Virginia Assembly that included various forms of amputation for certain crimes. This included rhinotomy for women. However, the bill never passed because some viewed it as too barbaric and others thought it was too lenient.

In some modern countries, judicial amputation is still used to punish those who commit crimes.

There are many different causes for the loss of a limb. Circulatory disorders, such as peripheral artery disease, can lead to gangrene. Severe infections like sepsis can also cause peripheral necrosis, where tissue dies. Trauma is another common cause, such as injuries sustained during war or accidents involving machinery. Frostbite is a specific type of injury caused by extreme cold. When skin freezes, ice crystals form in the tissue, leading to cell death. In rare, extreme situations, a person might even perform a self-amputation. A famous example is the hiker Aron Ralston, who amputated his own forearm after being pinned by a boulder for five days.

Modern science focuses heavily on restoring function through technology. A prosthesis is an artificial device used to replace a missing limb. Some advanced versions are bioelectric, meaning they use electrical signals to restore sensation or movement. Researchers are also testing the Agonist-antagonist Myoneural Interface, or AMI. This technology aims to give people better control over their prosthetic limbs. Even in sports, amputation can be a choice to improve performance. For instance, Australian Rules footballer Daniel Chick had a finger amputated to relieve chronic pain and help him play better.