What are growth plate injuries? Growth plates are areas of growing tissues that cause the long bones in children and teens to grow. Injuries to the growth plate happen when a break or fracture develops near or at the end of a long bone. The growth plate is the weakest part of the growing skeleton. Growth plate injuries usually happen at the: Bones of the legs. Wrist. Ankle. Foot. Hip bone. When you finish growing, the growth plates close and are replaced by solid bone.