T3 or Third Thoracic Vertebra, Inferior View

Description

Oriented from an inferior perspective, the T3 vertebra presents its heart-shaped vertebral body anteriorly, with the inferior demifacets positioned near the posterolateral margins for articulation with the head of the fourth rib. Posterior to the body, the vertebral foramen is bounded by the pedicles and laminae, and the spinous process projects posteriorly and slightly inferiorly in typical thoracic fashion. Laterally, the transverse processes extend to either side, and the inferior articular processes and facets sit posteroinferiorly to meet the superior articular facets of T4. Facet geometry tells the story. This underside view matters because the thoracic motion segment is defined as much by its costovertebral joints as by the intervertebral disc. The inferior demifacets on T3, together with the superior demifacets on T4, form the socket for the rib head, a relationship that explains why rib fractures, costovertebral sprains, or inflammatory arthropathies can refer pain to the upper back and be mistaken for “midline spine” pathology. For procedural anatomy, it also reinforces how thoracic facet orientation favors rotation and limits flexion and extension, a point that becomes concrete when you track the inferior articular facets toward their T4 counterparts. Use this illustration in thoracic spine teaching for gross anatomy, osteology practicals, and radiology correlation when identifying T-levels on axial CT or when explaining costovertebral joint involvement in ankylosing spondylitis. It also supports spine surgery and pain medicine materials that need clean bony landmarks for level localization and posterior element orientation at the upper thoracic region. Anatomical accuracy verified by SciePro's Medical Advisory Board.