What is it?
A bunion is a deformity of the joint that connects the big toe to the foot. It looks slightly like there would be something extra inside the foot making it look swollen. In reality, the joint has just been forced to such position, that while it forces the big toe towards the other toes, the end of it is consequentially pushed away from the toes to form a ball-resembling deformity near the beginning of the big toe .
In addition to the deformity itself, in a bunion there is also often skin irritation around the bunion, pain when walking, pain and redness of the joint, and a shift of the big toe towards the other toes. The painfulness of bunions is mostly due to the fact that a big part of your body weight rests on that particular joint while walking, so the harm caused by any deformities escalates quickly, as your weight starts to damage the joint that is not in the correct position.
Bunions are far more common in women than in men. The symptoms usually become noticeable between the ages 30-60.
What causes it?
There is some fairly solid evidence indicating that bunions are caused by using too tight or badly fitting shoes. There probably also exist some genetically predisposing factors. The shoes can exert pressure on the side of the big toe, pushing it towards the other toes. Pointed toe shoes, popular among women, are particularly bad. When people from cultures where shoes aren’t used have been examined, no cases of bunions have been found.
How can it be treated?
The symptoms of bunions can be treated by relieving the foot’s stress: this can be achieved through more spacious shoes, using padding and shields in the shoes, and resting. The deformity itself is more tricky to get rid of. If it gets too painful, surgery can be necessary.
Sources: https://en.wikipedia.org/wiki/Bunion, http://emedicine.medscape.com/article/1235796-overview#a11, http://www.mayoclinic.org/diseases-conditions/bunions/basics/causes/con-20014535