Disappearance of the fracture line is an X-ray or CT manifestation of clinical healing of a fracture. When the fracture is not healed, and the fracture has been fixed by cast or surgical reduction and fixation, the fracture is not healed when there is a low-density image in the early X-ray film and CT. If, after treatment, the low-density fracture line cannot be seen on repeat X-ray or CT, the fracture line disappears, and the disappearance of the fracture line is a sign of fracture healing. If the fracture line disappears and the patient’s limb movement is normal, the fracture is clinically healed, so the disappearance of the fracture line is a manifestation of fracture healing.