If the CPR method or force is not appropriate, will be pressed fracture, because the two palms of the force must be perpendicular, and should be placed on the top of the sternum, the position is the middle of the double nipple part, can not be deviated, if the position is deviated down in the force will lead to rib fracture. If the position is deviated, it will lead to rib fracture if the force is deviated. And the force should be pressed down vertically, if it is not pressed down vertically, the force will be deviated, which will lead to rib fracture. The elbow joint should be vertical when pressing, and the force of shoulder and back should be used to press down vertically. If the force, method and location are correct, it will not cause fracture in general.