Vertebral Column

Thoracic Vertebrae

The body of the eleventh frequently lacks the caudal demifacets, and the twelfth and thirteenth thoracic vertebrae always have one complete fovea on each side.  The fovea on the bodies of the vertebrae is for articulation with the heads of the ribs.  On thoracic vertebrae 11, 12, and 13, the right and left facets face each other across the median plane and are located at the base of the mamillary process.  The cranial articular facets, with the exception of those on the last three thoracic vertebrae, face forward and upward.  The caudal facets articulate with the cranial ones of the vertebra behind, and are similar in shape, and face downward and backward on thoracic vertebrae 1 to 9.