A rib fracture is a break or fracture in one or more of the bones making up the rib cage. Fractures of the first and second ribs may be more likely to be associated with head and facial injuries than other rib fractures. The middle ribs are the ones most commonly fractured. Fractures usually occur from direct blows or from indirect crushing injuries. A rib fracture has the complication of potentially causing a pulmonary contusion. Rib fractures are usually quite painful because the ribs have to move to allow for breathing. When several ribs are broken in several places a flail chest results, and the detached bone sections will move separately from the rest of the chest.