The metatarsals are the long bones in the foot that connect the toes to the midfoot. The metatarsals are numbered one through five, starting with the big toe. So the second metatarsal is the long bone of the second toe.
A second metatarsal shortening osteotomy is a procedure that cuts and shortens the second metatarsal. The goal of shortening the metatarsal is to decrease pain at the base of the second toe (in the ball of the foot) and/or help straighten out the second toe.