A fracture is a break in the continuity of a bone.  The chest wall is composed of multiple ribs that originate from the attachment to the spine in the back and extend around the chest to join in the front to the sternum and manubrium.  The ribs serve to encase the lungs and protect the contents of the chest.    Many muscles of respiration attach to the ribs and assist in the mechanics of breathing.  Fractured ribs usually occur from trauma, but can also occur due to tumors or spontaneously during coughing.  The pain and functional disability caused by fractured ribs is determined by the number of ribs involved, the severity of injury to the underlying tissue and organs and whether the fracture is partial or complete.  Flail chest is the name given to the condition when three or more ribs are fractured in more than one place and is a serious problem.  The pain of fractured ribs are worsened by taking a breath in (inspiration).  There may be reflex spasm of the muscles of the chest wall.  In  the absence of trauma, the pain of rib fractures can be mistaken for cardiac or gall bladder disease.  Fractured ribs are usually diagnosed by X-Ray.  In situations of trauma, CT scans and MRIs can look for damage to underlying organs and tissues.  Bone scans are useful to look for fractures that may be hard to see on xray or from invasion of the ribs by tumors.  Treatment begins with conservative modalities, including rest, heat, ice, non-steroidal anti-inflammatory medications and narcotics.  Injections under the ribs to block the nerves ( intercostal nerve blocks) can be very useful to provide pain relief in refractory cases.