A bunion is a bony swelling at the base of the big toe. The medical name for a bunion is hallux valgus.
The structure of the foot
The foot is made up of five bones called the metatarsals that join the heel bone to the bones inside the toes. Normally, the big toe is in line with the first metatarsal, the second toe with the second metatarsal, and so on.
Bunions
Sometimes, the big toe can become angled inwards, towards the middle of the foot and the second toe.
This can force the top of the first metatarsal to protrude (stick out) from the side of the foot, at the base of the big toe. If this happens, a painful, swollen bunion forms.
It is not known exactly why bunions occur, but wearing badly fitting shoes is thought to be a possible cause.
If bunions become worse over time, they can cause other problems, such as arthritis within the big toe joint.
Common treatments for bunions include:
- painkillers,
- bunion pads, and, in severe cases,
- surgery.
Who gets bunions?
Anyone can develop a bunion, but they affect up to a third more women than men.
Swelling
Inflammation is the body's response to infection, irritation or injury. It causes redness, swelling, pain and sometimes a feeling of heat in the affected area.
Joint
Joints are the connection point between two bones that allow movement.
Tissue
Body tissue is made up of groups of cells that perform a specific job, such as protecting the body against infection, producing movement or storing fat.
Deformity
Deformity is used to describe a part of the body that is not the usual shape. This could develop during pregnancy or as a result of a condition or injury.
Last updated: 04 October 2011
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