Joint or ligament | Description | Notes |
---|---|---|
costal cartilage | the cartilage that caps the medial end of the rib | costal cartilages of ribs 1-7 connect to the sternum; costal cartilages of ribs 8-10 connect to the costal cartilage of rib 7; costal cartilages of ribs 11 & 12 do not articulate anteriorly but end in the muscles of the abdominal wall |
radiate sternocostal ligaments | ligaments that reinforce the sternocostal joint capsule | these ligaments connect the costal cartilages of ribs 1-7 with the sternum on both the anterior and posterior surfaces of the sternocostal articulation |
sternal angle | the angle formed by the articulation between the manubrium and the body of the sternum | a synchondrosis; the cartilage within this joint usually does not become ossified until old age; the angle formed by this articulation is also called the angle of Louis; the sternal angle marks the level of the second costal cartilage from which all other ribs are counted |
sternocostal joints | the articulations that connect the costal cartilages with the sternum | a synchondrosis (rib 1) or synovial joints (ribs 2-10); sternocostal synovial joints involving ribs 2-7 contain thin joint capsules; interchondral joints involving ribs 8-10 have simple gliding synovial articulations; radiate sternocostal ligaments reinforce the sternocostal articulations |
xiphisternal joint | the articulation that connects the xiphoid process with the body of the sternum | a synchondrosis; the cartilage within this joint usually becomes ossified in old age; the xiphisternal joint marks the inferior extent of the thoracic cavity |