Final answer:
A bunion, also called hallux valgus, is a localized swelling on the medial side of the foot, at the base of the big toe. Wearing shoes with a narrow, pointed toe box, such as high heels, is most likely to cause the development of bunions.
Step-by-step explanation:
A bunion, also called hallux valgus, is a localized swelling on the medial side of the foot, next to the first metatarsophalangeal joint, at the base of the big toe. It is a common sign of osteoarthritis. Wearing shoes with a narrow, pointed toe box, such as high heels, is most likely to cause the development of bunions. The pressure from these shoes on the side of the foot can cause enlargement of the bone or inflammation of other tissues, pushing the big toe towards the other toes.