Joints of the thoracic wall
2. Joints of costal heads
The ribs articulate posteriorly with the thoracic vertebrae. A typical rib head has 2 articular facets. Both of them slop away from each other and there is a ridge between them. These facts make synovial joints with the demi facets in the vertebral body. The lower facet on a rib joins with the upper demi facet of its own rib. The upper facet of a rib joins with the lower demi facet of the vertebra above. The ridge between the facets is thus connected to the intervertebral disc by intra-articular ligament.
Example- The 3rd rib head joins with the upper demi facet of the T3, the intervertebral disc between T3-T2 and with the lower demi facet of the T2.
The 1st, 11th and 12th ribs are the exceptions for this articulation pattern. They articulate only with their own vertebrae; the T1, T11 and T12 respectively. So there aren't any attachment of the ribs to either the Cervical or the Lumbar vertebrae. (Some individuals may have an excess cervical rib that joins to the C7 vertebra)
The front of the costal head joint capsule is made strong by the radiate ligament. This ligament has 3 bands; the lower, upper and central. The lower band runs to the lower vertebral body, upper band runs to the upper vertebral body and the central band runs horizontally deep to anterior longitudinal ligament and fuse with the intervertebral disc.