The thoracic vertebrae like cervical one are divided into typical and atypical groups.
Typical thoracic vertebrae are distinguished by characteristic features of the typical thoracic vertebrae (T2 to T9) which are their costal facets, present on each side of the body (paired superior and inferior costal facet for articulation with the head of the ribs) and the transverse costal facet of the transverse processes for articulation with the tubercles of the ribs. The vertebral body is heart-shaped and the spinous process is long and directed inferiorly. The articular surfaces of the articular processes are directed in the frontal plane.
Typical thoracic vertebrae have:
Superior costal facet (fovea costalis superior) is usually bigger for the inferior part of the articular facet of the head of the rib.
Inferior costal facet (fovea costalis inferior) is usually smaller for the superior part of the articular facet of the head of the rib.
Intervertebral surface is the central part of the body with concavity on superior and inferior surface.
Anular epiphysis is a peripheral margin at the superior and inferior surfaces of the vertebral body.
Pedicle has superior and inferior vertebral notch above and beneath it.
Lamina of the vertebral arch.
Spinous process slopes downwards.
Transverse process has costal facet of transverse process (fovea costalis processus transversi) on the anterior for the tubercle of the rib.
Superior articular process is directed in frontal plane. It has posterior articular surface for vertebra above.
Inferior articular process is directed in frontal plane. It has anterior articular surface for vertebra below.
Vertebral foramen is ring-shaped
Atypical thoracic vertebrae (T1, T10, T11, T12) are distinguished by characteristic features, so it is possible to identify all of them.
T1 is distinguished by:
- Uncus of body (like in typical cervical vertebrae).
- Triangular vertebral foramen (like in typical cervical vertebrae).
- Round superior costal facet on the sides of the vertebral body.
T10 is distinguished by:
- Single (almost round) costal facet on the sides of the body on the level of the superior margin of the body.
- No articular facet on the transverse processes.
T11 is distinguished by:
- Single (round) costal facet on the sides of the body on the middle level of the body.
- Lack of an articular facet on the transverse processes.
T12 is distinguished by:
- Single (round) costal facet on the sides of the body on the level of the inferior margin of the body.
- Inferior articular processes are directed sagittally like in the lumbar vertebrae (for vertebra below) which have lateral articular surfaces.
- Lack of an articular facet on small transverse processes.
Clinical comments
Hunchback or kyphoscoliosis is an abnormal outward curvature of the vertebral column in the thoracic region. In most cases kyphoscoliosis may be congenital, but it can also result from poor posture or uneven growth of the vertebrae. Before the advent of effective anti-TB drugs, and the thoracic vertebrae close proximity to the lungs, kyphoscoliosis could be acquired due to Pott’s disease a form of tuberculosis.
