An avulsion is a tearing away or separation by force of any part of
the body from the whole. Thus, an avulsion means that a body part
has been separated from its point of attachment. The picture to the
right shows an avulsion fracture of the tumb, designated by the area
pointed to with the arrow.

Some avulsions occur by accident, such as a muscle tear during an
injury or the removal of layers of skin from an abrasion. It can also
refer to kind of limb amputation where the limb is torn off rather than
cut off.
FEATURED BOOK: Handbook of Fractures

Avulsions can also be done purposely during surgery. An example would be when veins
are stripped from the leg in the treatment of varicose veins (also known as spider veins).
Varicose veins is a condition in which valves in the veins of the legs do not work
properly, causing them to become swollen and distorted. A valve is a natural structure or
man-made device in a passageway, tube, vessel, or hollow organ that allows fluid or
partly fluid contents to travel in one direction, but closes to prevent the flow of those
contents in the opposite direction. Veins are blood vessels that carry blood to the heart.

There is also a type of fracture known as an avulsion fracture in which a piece of bone
tears away from the main body of bone due to physical trauma. Avulsion comes from the
Latin word "avulsio" meaning "a pulling away."
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