A bunion or hallux valgus results from a drifting outwards of the big toe from its normal position closer to the second metatarsal. The bunion is the head of this first metatarsal which produces the prominence on the inner side of the foot. In a bunion, with the shift/displacement of the first metatarsal tendons no longer lie in the correct axis and in fact act as a deforming force, contributing to the bunion condition.
Patients with bunions or hallux valgus tend to have pain on the metatarsal head on the inner border of the foot. It tends to be painful when in enclosed shoes and more so in winter. The pain which a bunion produces on the 2nd toe is either due to direct rubbing between the great toe and the 2nd toe, a hammer toe type deformity produced due to crowding of the 2nd toe by the bunion and the 3rd toe. The hammer toe will either be painful from its top aspect where it rubs directly on shoe wear or it's under surface in the area of the 2nd metatarsal head.
Treatment is directed at avoiding the causative factors, and using the appropriate footwear. Spacers and braces for keeping toes apart may work for a while, but severe cases do require surgical correction of the bone by straightening and removing the excessive bony prominence.