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Anterior External Vertebral Plexuses
The external vertebral venous plexuses (extraspinal veins) consist of anterior and posterior plexuses which anastomose freely with each other. They are most prominent in the cervical region where they form anastomoses with the vertebral, occipital, and deep cervical veins. * The anterior external vertebral venous plexuses are situated anteriorly to the vertebral bodies. They communicate with the basivertebral and intervertebral veins, and receive tributaries from the vertebral bodies. * The posterior external vertebral venous plexuses are situated posterior to the vertebral laminae, around and the spinous, transverse, and articular processes. They form anastomoses with the internal vertebral venous plexuses, and drain to vertebral veins, posterior intercostal veins, and lumbar veins The lumbar veins are four pairs of veins running along the inside of the posterior abdominal wall, and drain venous blood from parts of the abdominal wall. Each lumbar vein accompanies a single lum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thoracic Vertebra
In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebra (anatomy), vertebrae of intermediate size between the cervical and lumbar vertebrae; they increase in size going towards the lumbar vertebrae. They are distinguished by the presence of Zygapophysial joint, facets on the sides of the bodies for Articulation (anatomy), articulation with the head of rib, heads of the ribs, as well as facets on the transverse processes of all, except the eleventh and twelfth, for articulation with the tubercle (rib), tubercles of the ribs. By convention, the human thoracic vertebrae are numbered T1–T12, with the first one (T1) located closest to the skull and the others going down the spine toward the lumbar region. General characteristics These are the general characteristics of the second through eighth thoracic vertebrae. The first and ninth through twelfth v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anastomosis
An anastomosis (, : anastomoses) is a connection or opening between two things (especially cavities or passages) that are normally diverging or branching, such as between blood vessels, leaf veins, or streams. Such a connection may be normal (such as the foramen ovale in a fetus' heart) or abnormal (such as the patent foramen ovale in an adult's heart); it may be acquired (such as an arteriovenous fistula) or innate (such as the arteriovenous shunt of a metarteriole); and it may be natural (such as the aforementioned examples) or artificial (such as a surgical anastomosis). The reestablishment of an anastomosis that had become blocked is called a reanastomosis. Anastomoses that are abnormal, whether congenital or acquired, are often called fistulas. The term is used in medicine, biology, mycology, geology, and geography. Etymology Anastomosis: medical or Modern Latin, from Greek ἀναστόμωσις, anastomosis, "outlet, opening", Greek ana- "up, on, upon", stoma "mouth" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebral Vein
The vertebral vein is formed in the suboccipital triangle, from numerous small tributaries which spring from the internal vertebral venous plexuses and issue from the vertebral canal above the posterior arch of the atlas. They unite with small veins from the deep muscles at the upper part of the back of the neck, and form a vessel which enters the foramen in the transverse process of the atlas, and descends, forming a dense plexus around the vertebral artery, in the canal formed by the transverse foramina of the upper six cervical vertebrae In tetrapods, cervical vertebrae (: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In saurop .... This plexus ends in a single trunk, which emerges from the transverse foramina of the sixth cervical vertebra, and opens at the root of the neck into the back part of the innominate vein ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occipital Vein
The occipital vein is a vein of the scalp. It originates from a plexus around the external occipital protuberance and superior nuchal line to the back part of the vertex of the skull. It usually drains into the internal jugular vein, but may also drain into the posterior auricular vein (which joins the external jugular vein). It drains part of the scalp. Structure The occipital vein is part of the scalp. It begins as a plexus at the posterior aspect of the scalp from the external occipital protuberance and superior nuchal line to the back part of the vertex of the skull. It pierces the cranial attachment of the trapezius and, dipping into the venous plexus of the suboccipital triangle, joins the deep cervical vein and the vertebral vein. Occasionally it follows the course of the occipital artery, and ends in the internal jugular vein. Alternatively, it joins the posterior auricular vein, and ends in the external jugular vein. The parietal emissary vein connects it with the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Cervical Veins
The deep cervical vein (posterior vertebral vein or posterior deep cervical vein) is the vena comitans of the deep cervical artery. The vein is formed in the suboccipital region by the convergence of communicating branches of the occipital vein, veins draining the suboccipital muscles, and veins from the venous plexuses that surround cervical nerves. The vein and corresponding artery then pass in between the semispinalis capitis muscle and the semispinalis colli muscle. The vein passes anterior-ward in between the transverse process Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spina ... of the 7th cervical vertebra and the neck of the first rib to terminate in the vertebral vein. References External links Veins of the head and neck {{circulatory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basivertebral
The basivertebral veins are large, tortuous veins of the trabecular bone of vertebral bodies that drain into the internal and external vertebral venous plexuses. They emerge from the vertebral bodies horizontally through foramina in the bone. Anteriorly, they drain into the external vertebral venous plexuses; posteriorly, they drain into the anterior internal vertebral venous plexus by way of transverse vessels that bridge the two vertical anterior internal vertebral plexus vessels across the midline. Anatomy They are contained in large, tortuous channels in the bony substance of the vertebral bodies akin to those in the diploë of the cranial bones. Anteriorly and laterally, they emerge through small foramina upon the vertebral bodies to drain into the external vertebral plexus, whereas posteriorly, they converge into a single canal (which is sometimes doubled distally) before emptying into the internal vertebral plexus. The posterior longitudinal ligament The posterior longi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intervertebral Veins
The intervertebral veins accompany the spinal nerves through the intervertebral foramina to drain the internal vertebral venous plexuses into the external vertebral venous plexuses. They drain (in craniocaudal sequence) into vertebral vein, intercostal veins, lumbar veins, and lateral sacral veins. Upper posterior intercostal veins may additionally drain via brachiocephalic vens. They may drain to ascending lumbar veins. They may drain into the inferior vena cava directly, reaching it by winding around the surface of the vertebral body. It is unclear whether intervertebral veins contain functional venous valves; blood flow through intervertebral veins may be reversible, suggesting a possible mechanism for metastatic spread of e.g. prostatic cancer to the spine during temporary blood flow reversals (e.g. during periods of elevated intra-abdominal pressure or during postural alterations). Anatomy Fate Their drainage depends upon the part of the body: * Cervical region: verteb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebral Bodies
Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spinal segment and the particular species. The basic configuration of a vertebra varies; the vertebral body (also ''centrum'') is of bone and bears the load of the vertebral column. The upper and lower surfaces of the vertebra body give attachment to the intervertebral discs. The posterior part of a vertebra forms a vertebral arch, in eleven parts, consisting of two pedicles (pedicle of vertebral arch), two laminae, and seven processes. The laminae give attachment to the ligamenta flava (ligaments of the spine). There are vertebral notches formed from the shape of the pedicles, which form the intervertebral foramina when the vertebrae articulate. These foramina are the entry and exit conduits for the spinal nerves. The body of the vertebra and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Vertebral Venous Plexuses
The internal vertebral venous plexuses (intraspinal veins) lie within the vertebral canal in the epidural space, embedded within epidural fat. They receive tributaries from bones, red bone marrow, and spinal cord. They are arranged into four interconnected, vertically oriented vessels - two situated anteriorly, and two posteriorly: *The anterior internal vertebral venous plexus consists of two large plexiform veins situated upon the posterior surfaces of the vertebral bodies and intervertebral discs on either side of the posterior longitudinal ligament (underneath this ligament they are interconnected by transverse branches into which the basivertebral veins open). * The posterior internal vertebral venous plexus consists of two veins situated - one on either side - upon the anterior aspect of the vertebral arches and ligamenta flava. They form anastomoses with posterior external plexuses by way of veins passing through or between the ligamenta flava. The anterior and posterior i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebral Vein
The vertebral vein is formed in the suboccipital triangle, from numerous small tributaries which spring from the internal vertebral venous plexuses and issue from the vertebral canal above the posterior arch of the atlas. They unite with small veins from the deep muscles at the upper part of the back of the neck, and form a vessel which enters the foramen in the transverse process of the atlas, and descends, forming a dense plexus around the vertebral artery, in the canal formed by the transverse foramina of the upper six cervical vertebrae In tetrapods, cervical vertebrae (: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In saurop .... This plexus ends in a single trunk, which emerges from the transverse foramina of the sixth cervical vertebra, and opens at the root of the neck into the back part of the innominate vein ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lumbar Veins
The lumbar veins are four pairs of veins running along the inside of the posterior abdominal wall, and drain venous blood from parts of the abdominal wall. Each lumbar vein accompanies a single lumbar artery. The lower two pairs of lumbar veins all drain directly into the inferior vena cava, whereas the fate of the upper two pairs is more variable. Lumbar veins are the lumbar equivalent of the posterior intercostal veins of the thorax. Structure A lumbar vein accompanies each of the four lumbar arteries on each side of the body. Distribution and tributaries Collectively, the lumbar veins drain blood from the territories supplied by the corresponding lumbar arteries (the posterior, lateral, and anterior abdominal wall). The lumbar veins drain the anterior spinal veins. Fate The 3rd and 4th lumbar veins drain into the inferior vena cava. The fate of the two superior lumbar veins is far more variable, and may drain into either the inferior vena cava, ascending lumbar v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
