Costal-vertebral joints

Costal-vertebral joints. The posterior ends of the ribs are articulated with vertebrae using two joints:

I. The joint of the head of the rib, articulatio capitis costae, is formed by the articular surface of the head of the rib and the fossa of the vertebral bodies. The head from II to X of the ribs is conical and in contact with the corresponding joint pits of the bodies of two vertebrae.

The articular surfaces on the vertebral bodies are in most cases formed by two pits: the smaller upper costal fossa, fovea costalis superior, which is located in the lower part of the body of the overlying vertebra, and the larger inferior fossa fovea costalis inferior, lying at the upper edge of the underlying vertebra. The ribs I, XI and XII are articulated only with the fossa of one vertebra. The articular surfaces of the costal pits of the vertebrae and ribs are covered with fibrous cartilage.

In the joint cavity of the II-X ribs, there is an intraarticular ligament of the rib head, lig. Capitis costae intraarticulare. It is directed from the crest of the rib head to the intervertebral disc and divides the joint cavity into two chambers. The joint capsule is thin and reinforced with a radial ligament of the rib head, lig. Capitis costae radiatum, which originates from the anterior surface of the rib head and is attached fan-shaped to the higher and lower vertebrae and intervertebral disc.

2. The costal-transverse joint, aniculatio castotransversaria, is formed by articulation of the articular surface of the rib bump, facies articularis tuberculi costae, with the costal fossa of the transverse processes of the thoracic vertebrae. These joints are only present in the 10 upper ribs. The articular surfaces are covered with hyaline cartilage, the joint capsule is fissile, attached to the edge of the articular surfaces.

The joint is strengthened by numerous ligaments:

A) the superior costal-transverse ligament, lig. Costotransversarium superius, originates from the lower surface of the transverse process and is attached to the crest of the neck of the underlying rib;

B) lateral rib-transverse ligament, lig. Costotransversarium laterale, stretched between the bases of the transverse and spinous processes and the posterior surface of the neck of the underlying rib;

C) rib-transverse ligament, lig. Costotransversarium, lies between the posterior surface of the cervical rib and the anterior surface of the transverse process of the corresponding vertebra, filling the costal-transverse aperture, foramen costotransversarium;

D) lumbar-rib bundle, lig. Lumbocostate, - a thick fibrous plate stretched between the costal processes LI and LII and the lower edge of the XII rib. It fixes the rib and simultaneously strengthens the aponeurosis of the transverse abdominal muscle.

The joints of the head and the tubercle of the rib are in the form of cylindrical joints, and they are functionally connected: in the act of breathing, movements occur simultaneously in both joints.