MODEL RELEASED. Bunion on a man's foot post surgery (right foot). Corrective surgery removed an excess of growth at the side of the joint and straightened the big toe. A bunion is a fluid- filled pad that covers the joint of the big toe on the foot at left. The majority of bunions are caused by the condition hallux valgus, in which the big toe (hallux) bends inwards and the base of the joint protrudes. The continued rubbing of the joint on tight shoes leads to inflammation and a bunion. Bunions can be very painful and they will increase in size unless correctly-fitting shoes are worn. Shoes which force the big toe into a straight position will help relieve small bunions, but larger ones may require surgery to correct the shape of the joint.