bunions
Last reviewed 01/2018
A bunion is a protective bursa that develops over the metatarsal head where a shoe rubs. This is characteristic of hallux valgus. Otherwise it may be an exostosis on the metatarsal.
The bursa may become infected, and there is a risk of infection involving the first metatarsophalangeal joint. Infection is complicated by conditions such as diabetes mellitus or rheumatoid arthritis.