Costovertebral joint
The costovertebral joint is the articulations between the ribs and the vertebral column.
Gross Anatomy
The ribs articulate with the thoracic vertebrae via two distinctly different joints:
Costovertebral Joint
The head of a typical rib has two facets separated by a ridge. The lower rib facet articulates with the upper costal facet of its own vertebra and the upper facet articulates with the lower facet of the vertebral body above. Each facet is a separate synovial joint. The first rib articulates with the T1 vertebra only and the lowest three ribs articulate only with their own vertebral body . There are two types of ligaments:
- intra-articular ligament - attaches the intervertebral disc to the ridge in between the two facets of the head of the rib.
- radiate ligament - formed by three bands which connect the rib head to the vertebral bodies. A superior band runs to the vertebral body above and an inferior band runs to the vertebral body below. A central band runs deep to the anterior longitudinal ligament and blends into the intervertebral disc to join the ligament on the opposite side. In the first rib and the last three ribs, only two bands exist as they only articulate with their own vertebra.
Costotransverse Joint
There are two facets of a tubercle of a rib, the medial and lateral. The hyaline cartilage-lined medial facet forms a plane synovial joint with the tip of the transverse process which is reinforced by a capsule. The lateral facet is attached to the transverse process through three ligaments :
The lower two ribs are only attached by ligaments and do not form synovial joints with the transverse process.