The thoracic region of the vertebral column is composed of twelve thoracic vertebrae (T1-T12).  Except for last two, the transverse processes of these vertebrae bear facets that articulate with the tubercles of the ribs.  The bodies of the thoracic vertebrae also have half facets (demifacets) for articulation with the heads of the ribs.  In their normal articulated position, the demifacets of adjacent vertebrae form whole facets for the heads of the ribs.