There are five metatarsal bones in each foot. These bones are the long bones behind each toe. The metatarsal bone behind the big toe is called the first metatarsal. The metatarsal bone behind the little toe is called the fifth metatarsal. The most common metatarsal surgery is performed on the first metatarsal for the correction of bunion deformity. The second most common metatarsal surgery is on the fifth metatarsal for the correction of tailor's bunion deformity.Painful calluses on the ball of the foot are due to an abnormal alignment of the metatarsal bones. If a metatarsal bone is lower than the others, excessive weight is placed on this area of the foot, and a painful callous may form. In people with diabetes, these areas of excessive pressure may break down and form open sores or ulcerations. Initial treatment generally consist of using a functional or accommodative orthotic to reduce the pressure to these areas. If this is not successful, metatarsal surgery may be considered.