Which thoracic vertebrae is

Become a Gold Supporter and see no ads. Log in Sign up. Articles Cases Courses Quiz. About Recent Edits Go ad-free. Edit article. View revision history Report problem with Article. Citation, DOI and article data. Palipana, D. Typical thoracic vertebrae. Reference article, Radiopaedia. Typical dorsal vertebra Typical dorsal vertebrae Typical thoracic vertebra. URL of Article. On this page:. Quiz questions. DSc SSP. Gray's Anatomy. Churchill Livingstone. Read it at Google Books - Find it at Amazon 2.

Last's Anatomy. Read it at Google Books - Find it at Amazon 3. McMinn and Abrahams' clinical atlas of human anatomy. Read it at Google Books - Find it at Amazon 4. Posterior to the vertebral bodies are thin bony rings known as the vertebral arches. Each vertebral arch surrounds and protects a hollow vertebral foramen that provides space for the spinal cord and spinal nerves.

A pair of transverse processes extends from the lateral sides of each vertebral arch to support the ribs and provide attachment sites for the rotatores and multifidus muscles of the back.

At the posterior end of the vertebral arch, each thoracic vertebra extends posteriorly and inferiorly to form the spinous processes. Each spinous process supports several muscles of the back to provide movement to the trunk and spine region.

The spinous processes also overlap each other slightly to provide extra support and rigidity to the thoracic region and prevent extraneous movements. Two pairs of articular processes extend superiorly and inferiorly toward the neighboring vertebrae, in order to help stabilize the spine and connect the thoracic vertebrae to one another and to the C7 and L1 vertebrae. Flat planar joints form between the articular processes of these neighboring vertebrae, allowing the bones to move independently while maintaining the strength and stability of the spinal column.

The superior articular processes end in smooth surfaces facing posteriorly to meet the articular process of the vertebra above. On the inferior end, the inferior articular processes end in smooth, flat surfaces facing anteriorly to meet the next vertebra. The T1 and T12 vertebrae are the exceptions to this rule; T1 features a superior articular process resembling those of the cervical vertebrae, while the inferior articular process of T12 resembles those of the lumbar vertebrae.

The length of the transverse processes decreases as the column descends. The positioning of the ribs and spinous processes greatly limits flexion and extension of the thoracic vertebrae. However, T5-T8 have the greatest rotation ability of the thoracic region. Thoracic vertebrae have superior articular facets that face in a posterolateral direction. The spinous process is long, relative to other regions, and is directed posteroinferiorly.

This projection gradually increases as the column descends before decreasing rapidly from T9-T The intervertebral disc height is, on average, the least of the vertebral regions. They alone articulate with the first rib; C7 has no costal facets.

T1 does, however, have typical inferior demifacets for articulation with the second rib. T1 also has a long, almost horizontal spinous process, similar to a cervical vertebra that may be as long as the vertebra prominens of C7. They also lack facets on the transverse processes. It varies by individual, but T10 may resemble the atypical nature of the 11 and 12 vertebrae. When that is the case, T9 lacks an inferior demifacet, as it would not be needed to articulate with the 10th rib.

Additionally, T12 is unique in that it represents a transition from the thoracic to the lumbar vertebra.