Articulation of head of rib

The articulations of the heads of the ribs (or costocentral articulations) constitute a series of gliding or arthrodial joints, and are formed by the articulation of the heads of the typical ribs with the costal facets on the contiguous margins of the bodies of the thoracic vertebrae and with the intervertebral discs between them; the first, tenth, eleventh and twelfth ribs each articulate with a single vertebra. Two convex facets from the head attach to two adjacent vertebrae, at the inferior costal facet of the superior vertebra, and the superior costal facet of the inferior vertebra respectively.

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