Question: where does the head of the rib articulate with
Answer: 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 facets on the contiguous margins of the bodies of the thoracic vertebrae and with the intervertebral fibrocartilages between them ; the first , eleventh and twelfth ribs each articulate with a single vertebra .