Painful calluses on the ball of the foot are caused by an abnormal alignment of the metatarsal bones. There are five metatarsal bones in each foot, each consisting of the long bones behind each toe. The metatarsal bone behind the big toe is called the first metatarsal, and so on.

The most common metatarsal surgery is performed on the first metatarsal for the correction of bunions.

Surgery on the second through fifth metatarsal bones is performed infrequently, and is usually done to treat painful calluses on the bottom of the foot or non-healing ulcers on the ball of the foot. Patients with rheumatoid arthritis may also need metatarsal surgery.

During surgery, the metatarsal bone is cut just behind the toe. Generally, the bone is cut all the way through, and then manually raised and held in its corrected position with a metal pin or screw. Following the surgery, the patient's foot may be placed in a cast.

In some instances, a surgeon will also cut out the painful callous on the bottom of the foot, but most prefer to do the procedure in an outpatient setting.