Typical thoracic vertebrae
Given the twelve thoracic vertebrae are largely similar, most are considered typical thoracic vertebrae with the exceptions T1 and T9 to T12. For a basic anatomic description of the structure of typical vertebrae, see vertebrae.
Terminology
In medical English, some doctors and texts refer to the dorsal spine, D-spine and D1-D12, however, we discourage this usage on Radiopaedia preferring thoracic spine, T-spine and T1-T12. This is consistent with Terminologia Anatomica, which solely employs the thoracic designator to refer to this part of the spine. However, in French-speaking parts of the world, D1-D12 are commonly used interchangeably with T1-T12 .
Gross anatomy
Relative to cervical and lumbar vertebrae, thoracic vertebrae have:
- medium-sized, heart shaped vertebral bodies
- medium-sized vertebral canal
- prominent transverse processes with costal facets
- long spinous processes angulating downwards
Osteology
Anterior components of thoracic vertebrae:
- body
- pedicle
- superior and inferior costal demifacets
Posterior components of typical thoracic vertebrae:
- downward angled spinous processes
- transverse processes
- superior and inferior articular facets
- transverse costal facets
- lamina
- intervertebral foramen
Articulations
Ribs
Each vertebra contains three points of articulation with ribs.
The superior demifacet of a thoracic vertebra articulates with the corresponding rib (costovertebral joint). This rib articulates again with the costal facet on the transverse process (costotransverse joint). The inferior demifacet articulates with the rib below.
For example, the superior demifacet and costal facet on the transverse process of T5 will articulate with the fifth rib. The inferior demifacet of T5 will articulate with the sixth rib.
Facet (zygapophyseal) Joints
The superior articular process arises from the upper border of the pedicle. An oval facet faces posterolaterally.
The inferior articular process arises from the lower border of the pedicle. The facet faces anteromedially.
Intervertebral discs
Similar to other vertebrae, discs are interposed between hyaline cartilage on the centrum of the vertebral bodies. The disc height is slightly less than cervical vertebrae.
Radiographic features
Plain radiograph
- anteroposterior and lateral orthogonal is used to demonstrate the thoracic spine
- swimmers view allows better visualization of the cervicothoracic area if the upper thoracic spine needs to be evaluated
Related pathology
