All ribs have dorsal bony and ventral cartilaginous parts that meet at a costochondral junction. The cartilaginous parts are called costal cartilages. The bony part of a rib possesses a head, neck and body. The head of ribs 1 through 10 articulate with the costal fovea of two contiguous vertebrae and the intervening fibrocartilatge. Ribs 11 through 13 the head articulates only with the cranial costal fovea on the body of the vertebra of the same number. The tuberculum articulates with the costal fovea of the transverse process of the vertebra. The neck is found between the head and tuberculum on the proximal part of the rib.