Sternum

The sternum, or breastbone is made up of three separate bones. They are the manubrium, (the uppermost part of the sternum) the central body and the xiphoid process (the bottom of the sternum). The ribs attach to the sternum via costal cartilages to the costal notches of the sternum, which lie on the outer side of the sternum. At the top of the manubrium there are two more articulating notches called the sternal notch and the clavicular notch. The clavicular notches, which lay either side of the sternal notch, are for articulation with the clavicles. The manubrium is the attachment point for the first and second pairs of ribs. The sternum body is the attachment point for ribs 3 through 10. The xiphoid has no attachment with the ribs but is an attachment point for abdominal muscles