This begins at the thoracolumbar junction and proceeds in the cranial and caudal directions. The neural processes fuse with the centrum in between three and six years of age.
During puberty, five secondary ossification centers develop at the tip of the spinous process and both transverse processes and on the superior and inferior surfaces of the vertebral body.
The ossification centers on the vertebral body are responsible for the superior-inferior growth of the vertebrae. Ossification completes around the age of The thoracic vertebrae are mainly supplied by branches of the posterior intercostal arteries.
The first two posterior intercostal arteries branch off the subclavian artery, while the remaining branch off the thoracic aorta. These main arteries branch out into the periosteal and equatorial arteries, which subsequently branch into anterior and posterior canal branches. Anterior vertebral canal branches send nutrient arteries into the vertebral body to supply the red marrow. Spinal veins form venous plexuses inside and outside the vertebral canal.
These plexuses are valve-less and allow for the movement of blood superiorly or inferiorly depending on pressure gradients. The blood eventually drains into the segmental veins of the trunk.
The thoracic spine has a relatively narrow vertebral canal, which predisposes it to spinal cord damage and neurological deficit. However, the thoracic spine is functionally rigid due to the orientation of the facet joints, the thin intervertebral discs, and the ribcage.
Therefore, it requires a greater amount of energy force of trauma to produce fractures and dislocations. As T12 has characteristics of both thoracic and lumbar vertebrae, it is subject to transitional stresses. These transitional forces result from the change from the rigid thoracic spine to the relatively mobile lumbar spine. This causes it to be the most commonly fractured vertebra. The valve-less vertebral venous plexuses allow the metastasis of cancer from the pelvis, such as that of the prostatic, to the vertebral column.
Medical science monitor : international medical journal of experimental and clinical research. The Journal of heart valve disease. Bogduk N, Functional anatomy of the spine. Handbook of clinical neurology. World neurosurgery. Anatomy, Back, Thoracic Vertebrae. 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. Snell RS. Clinical Anatomy By Regions Internationa. Read it at Google Books - Find it at Amazon 5. Learning radiology. Read it at Google Books - Find it at Amazon 6. Grainger's and Allison's Diagnostic Radiology. Read it at Google Books - Find it at Amazon 7. Ann Wiles. Ann's Acronyms: T versus D. Caduceus [accessed 10 March ]. Related articles: Anatomy: Spine. Promoted articles advertising. Figure 1a: typical thoracic vertebra Gray's illustration Figure 1a: typical thoracic vertebra Gray's illustration.
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.
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