The skull is a relatively tough bone, when the top of the head is hit, usually not too serious problems, because the patient has the protection of the skull. Infants and young children hit in the head, because the development of infants and young children’s skull is not yet complete, the skull itself is relatively weak, when the top of the head of the child is hit, will not give adults a hint, this situation should be careful, need to go to the hospital in a timely manner to carry out CT and other checks. If a serious violent impact, the patient appeared limb numbness, weakness, coma, need to go to the hospital in time for CT examination, to exclude the skull depressed fracture, cerebral contusion, intracerebral hematoma and so on.