Bunion or hallux valgus is an abnormal bony bump formed due to enlargement of the bone or soft tissues around the joint at the base of the big toe. Bunions cause deviation of the big toe towards other toes and pushes the first metatarsal bone outwards on the other side. Bunions formed on the little toe and fifth metatarsal are called Bunionettes. Excessive pressure and friction on the bunion by footwear can further lead to development of a callus (painful area of thickened skin).
Bunion surgery is performed to relieve pain and realign or remove the soft tissues or bone causing the joint deformity.