Vertebral foramen

In a typical vertebra, the vertebral foramen is the foramen (opening) formed by the anterior segment (the body), and the posterior part, the vertebral arch.

The vertebral foramen begins at cervical vertebra #1 (C1 or atlas) and continues inferior to lumbar vertebra #5 (L5).

The vertebral foramen houses the spinal cord and its meninges. This large tunnel running up and down inside all of the vertebrae contains the spinal cord and is typically called the spinal canal, not the vertebral foramen.

Vertebral foramen
Foramenvertebrale
A typical thoracic vertebra, viewed from above. (Vertebral foramen is the large hole at the center.)
Gray84
A cervical vertebra. (Vertebral foramen is the large hole at the center.)
Details
Identifiers
Latinforamen vertebrale
TAA02.2.01.011
FMA13479
Anatomical terms of bone

See also

References

External links

  • Anatomy figure: 02:01-06 at Human Anatomy Online, SUNY Downstate Medical Center - "Superior and lateral views of typical vertebrae"
  • Vertebral foramen - BlueLink Anatomy - University of Michigan Medical School
  • Atlas image: back_bone16 at the University of Michigan Health System - "Typical Lumbar Vertebra, Superior View; Lumbar Vertebral Column, Oblique Lateral View"
Atlas (anatomy)

In anatomy, the atlas (C1) is the most superior (first) cervical vertebra of the spine.

It is named for the Atlas of Greek mythology, because it supports the globe of the head which is the skull.The atlas is the topmost vertebra and with the axis forms the joint connecting the skull and spine. The atlas and axis are specialized to allow a greater range of motion than normal vertebrae. They are responsible for the nodding and rotation movements of the head.

The atlanto-occipital joint allows the head to nod up and down on the vertebral column. The dens acts as a pivot that allows the atlas and attached head to rotate on the axis, side to side.

The atlas's chief peculiarity is that it has no body. It is ring-like and consists of an anterior and a posterior arch and two lateral masses.

The atlas and axis are important neurologically because the brain stem extends down to the axis.

Axis (anatomy)

In anatomy, the second cervical vertebra (C2) of the spine is named the axis (from Latin axis, "axle") or epistropheus.

By the atlanto-axial joint, it forms the pivot upon which the first cervical vertebra (the atlas), which carries the head, rotates.

The most distinctive characteristic of this bone is the strong odontoid process known as the dens which rises perpendicularly from the upper surface of the body. That peculiar feature gives to the vertebra a rarely used third name: vertebra dentata. In some judicial hangings the odontoid process may break and hit the medulla oblongata, causing death.

Back injury

Back injuries result from damage, wear, or trauma to the bones, muscles, or other tissues of the back. Common back injuries include sprains and strains, herniated discs, and fractured vertebrae. The lumbar spine is often the site of back pain. The area is susceptible because of its flexibility and the amount of body weight it regularly bears. It is estimated that low-back pain may affect as much as 80 to 90 percent of the general population in the United States.

Carolinacetus

Carolinacetus is an extinct protocetid early whale found in the Bartonian (40.4 to 37.2 mya) Tupelo Bay Formation (33.3°N 79.7°W / 33.3; -79.7, paleocoordinates 33.3°N 70.9°W / 33.3; -70.9) in Berkeley County, South Carolina.Carolinacetus is known from an incomplete cranium with portions of the right inner ear, a detached rostrum, and parts of both mandibles with 11 teeth. Preserved from the postcranium are 13 vertebrae and 15 ribs. The holotype was collected in 1994.Several anatomical features identifies Carolinacetus as a protocetid (and therefore as a member of Pelagiceti) including: external nares are located above the canine, the supraoccipital (in cetaceans, the part of the occipital bone located above the foramen magnum and directed backwards) is narrow and tubular, accessory cusps absent on M3, a broad connection between the ectotympanic bulla and the falciform process of the squamosal, axis vertebra with large vertebral foramen.In Carolinacetus the naral openings are located in front of P1, making it the most basal North American cetacean. Carolinacetus is distinct from other North American cetaceans, it is 8-15% larger than Georgiacetus and differs from it in several cranial characters.

Cervical vertebrae

In vertebrates, cervical vertebrae (singular: vertebra) are the vertebrae of the neck, immediately below the skull.

Thoracic vertebrae in all mammalian species are those vertebrae that also carry a pair of ribs, and lie caudal (toward the tail) to the cervical vertebrae. Further caudally follow the lumbar vertebrae, which also belong to the trunk, but do not carry ribs. In reptiles, all trunk vertebrae carry ribs and are called dorsal vertebrae.

In many species, though not in mammals, the cervical vertebrae bear ribs. In many other groups, such as lizards and saurischian dinosaurs, the cervical ribs are large; in birds, they are small and completely fused to the vertebrae. The vertebral transverse processes of mammals are homologous to the cervical ribs of other amniotes. Most mammals have 7 cervical vertebrae.In humans, cervical vertebrae are the smallest of the true vertebrae, and can be readily distinguished from those of the thoracic or lumbar regions by the presence of a foramen (hole) in each transverse process, through which the vertebral artery, vertebral veins and inferior cervical ganglion pass.

The remainder of this article focuses upon human anatomy.

Degenerative disc disease

Degenerative disc disease (DDD) is a medical condition (ICD-10-CM M51.35-37) in which there are anatomic changes and a loss of function of varying degrees of one or more intervertebral discs of the spine of sufficient magnitude as to cause symptoms. The root cause is thought to be loss of soluble proteins within the fluid contained in the disc with resultant reduction of the oncotic pressure, which in turn causes loss of fluid volume. Normal downward forces cause the affected disc to lose height, and the distance between vertebrae is reduced. The anulus fibrosus, the rigid outer shell of a disc, also weakens. This loss of height causes laxity of the longitudinal ligaments, which may allow anterior, posterior, or lateral shifting of the vertebral bodies, causing facet joint malalignment and arthritis; scoliosis; cervical hyperlordosis; thoracic hyperkyphosis; lumbar hyperlordosis; narrowing of the space available for the spinal tract within the vertebra (spinal stenosis); and/or narrowing of the space through which a spinal nerve exits (vertebral foramen stenosis) with resultant inflammation and impingement of a spinal nerve, causing a radiculopathy.

DDD can cause mild to severe pain, either acute or chronic, near the involved disc, as well as neuropathic pain if an adjacent spinal nerve root is involved. Diagnosis is suspected when typical symptoms and physical findings are present; and confirmed by x-rays of the vertebral column. Occasionally the radiologic diagnosis of disc degeneration is made incidentally when a cervical x-ray, chest x-ray, or abdominal x-ray is taken for other reasons, and the abnormalities of the vertebral column are recognized. The diagnosis of DDD is not a radiologic diagnosis, since the interpreting radiologist is not aware whether there are symptoms present or not. Typical radiographic findings include disc space narrowing, displacement of vertebral bodies, fusion of adjacent vertebral bodies, and development of bone in adjacent soft tissue (osteophyte formation). An MRI is typically reserved for those with symptoms, signs, and x-ray findings suggesting the need for surgical intervention.

Treatment may include physical therapy to reduce pain and increase any reduced range of motion of the spine; strength training with emphasis on correcting abnormal posture, assisting the paravertebral (paraspinous) muscles in stabilizing the spine, and core muscle strengthening; stretching exercises; massage therapy; oral analgesia with non-steroidal anti-inflammatory agents (NSAIDS); and topical analgesia with lidocaine, ice and/or heat. Immediate surgery may be indicated if the symptoms are severe or sudden in onset, or there is a sudden worsening of symptoms. Elective surgery may be indicated after six months of conservative therapy with unsatisfactory relief of symptoms.

Dorsal root of spinal nerve

The dorsal root of spinal nerve (or posterior root of spinal nerve) is one of two "roots" which emerge from the spinal cord. It emerges directly from the spinal cord, and travels to the dorsal root ganglion. Nerve fibres with the ventral root then combine to form a spinal nerve. The dorsal root transmits sensory information, forming the afferent sensory root of a spinal nerve.

Foramen

In anatomy, a foramen (; pl. foramina, ) is any opening. Foramina inside the body of humans and other animals typically allow muscles, nerves, arteries, veins, or other structures to connect one part of the body with another.

Intervertebral foramen

The intervertebral foramen (also called neural foramen, and often abbreviated as IV foramen or IVF), is a foramen between two spinal vertebrae. Cervical, thoracic, and lumbar vertebrae all have intervertebral foramina.

The foramina, or openings, are present between every pair of vertebrae in these areas. A number of structures pass through the foramen. These are the root of each spinal nerve, the spinal artery of the segmental artery, communicating veins between the internal and external plexuses, recurrent meningeal (sinu-vertebral) nerves, and transforaminal ligaments.

When the spinal vertebrae are articulated with each other, the bodies form a strong pillar that supports the head and trunk, and the vertebral foramen constitutes a canal for the protection of the medulla spinalis (spinal cord).

The size of the foramina is variable due to placement, pathology, spinal loading, and posture.

Foramina can be occluded by arthritic degenerative changes and space-occupying lesions like tumors, metastases, and spinal disc herniations.

Specifically, the intervertebral foramen is bordered by the superior notch of the adjacent vertebra, the inferior notch of the vertebra, the intervertebral joint and the intervertebral disc.

Laminotomy

A laminotomy is an orthopaedic neurosurgical procedure that removes part of the lamina of a vertebral arch in order to relieve pressure in the vertebral canal. A laminotomy is less invasive than conventional vertebral column surgery techniques, such as laminectomy because it leaves more ligaments and muscles attached to the vertebral column intact and it requires removing less bone from the vertebra. As a result, laminotomies typically have a faster recovery time and result in fewer postoperative complications. Nevertheless, possible risks can occur during or after the procedure like infection, hematomas, and dural tears. Laminotomies are commonly performed as treatment for lumbar spinal stenosis and herniated disks. MRI and CT scans are often used pre- and post surgery to determine if the procedure was successful.

List of foramina of the human body

This page lists foramina that occur in the human body.

Lumbar vertebrae

The lumbar vertebrae are, in human anatomy, the five vertebrae between the rib cage and the pelvis. They are the largest segments of the vertebral column and are characterized by the absence of the foramen transversarium within the transverse process (since it is only found in the cervical region) and by the absence of facets on the sides of the body (as found only in the thoracic region). They are designated L1 to L5, starting at the top. The lumbar vertebrae help support the weight of the body, and permit movement.

Neurogenic claudication

Neurogenic claudication (NC), also known as pseudoclaudication, is a common symptom of lumbar spinal stenosis (LSS), causing impingement or inflammation of the nerves emanating from the spinal cord. Neurogenic means that the problem originates with a problem at a nerve, and claudication, from the Latin for limp, because the patient feels a painful cramping or weakness in the legs. NC should therefore be distinguished from vascular claudication, which is when the claudication stems from a circulatory problem, not a neural problem.

Neurogenic claudication may present in one or both legs and usually presents as some combination of discomfort, pain, numbness and weakness in the calves, buttocks, and/or thighs. In some patients, it is precipitated by walking and prolonged standing. The pain is classically relieved by a change in position or flexion of the waist. Although a flexed position may also potentially relieve symptoms, resting typically offers the greatest relief of pain.

Therefore, patients with neurogenic intermittent claudication have less disability in climbing steps, pushing carts and cycling. This is because those movements flex the lumbar spine, and the vertebral foramen widens.

The pathophysiology is thought to be ischemia of the lumbosacral nerve roots secondary to compression from surrounding structures, hypertrophied facets, ligamentum flavum, bone spurs, scar tissue, and bulging or herniated discs.

In addition to vascular claudication, pseudo-trochanteric bursitis should be considered in differential diagnosis.

Spinal canal

The spinal canal (or vertebral canal or spinal cavity) is the space in the vertebral column formed by the vertebrae through which the spinal cord passes. It is a process of the dorsal body cavity. This canal is enclosed within the vertebral foramen of the vertebrae. In the intervertebral spaces, the canal is protected by the ligamentum flavum posteriorly and the posterior longitudinal ligament anteriorly.

The outermost layer of the meninges, the dura mater, is closely associated with the arachnoid mater which in turn is loosely connected to the innermost layer, the pia mater. The meninges divide the spinal canal into the epidural space and the subarachnoid space. The pia mater is closely attached to the spinal cord. A subdural space is generally only present due to trauma and/or pathological situations. The subarachnoid space is filled with cerebrospinal fluid and contains the vessels that supply the spinal cord, namely the anterior spinal artery and the paired posterior spinal arteries, accompanied by corresponding spinal veins. The anterior and posterior spinal arteries form anastomoses known as the vasocorona of the spinal cord and these supply nutrients to the canal. The epidural space contains loose fatty tissue, and a network of large, thin-walled blood vessels called the internal vertebral venous plexuses.

Spinal stenosis is a narrowing of the canal which can occur in any region of the spine and can be caused by a number of factors.

The spinal canal was first described by Jean Fernel.

Stellate ganglion

The stellate ganglion (or cervicothoracic ganglion) is a sympathetic ganglion formed by the fusion of the inferior cervical ganglion and the first thoracic ganglion, which exists in 80% of cases. Sometimes the second and the third thoracic ganglia are included in this fusion. Stellate ganglion is relatively big (10-12 x 8-20 mm) compared to much smaller thoracic, lumbar and sacral ganglia and it is polygonal in shape (lat. stellatum meaning star-shaped). Stellate ganglion is located at the level of C7, anterior to the transverse process of C7 and the neck of the first rib, superior to the cervical pleura and just below the subclavian artery. It is superiorly covered by the prevertebral lamina of the cervical fascia and anteriorly in relation with common carotid artery, subclavian artery and the beginning of vertebral artery which sometimes leaves a groove at the apex of this ganglion (this groove can sometimes even separate the stellate ganglion into so called vertebral ganglion).

Relations of the apex of the stellate ganglion:

• covered by the endothoracic fascia and parietal pleura

• right stellate ganglion is in relation with right brachiocephalic vein anteriorly

• right stellate ganglion is in relation with sternal part of subclavian artery anteriorly

• laterally: first intercostal artery

• medially: longus colli muscle

T-bone steak

The T-bone and porterhouse are steaks of beef cut from the short loin (called the sirloin in Commonwealth countries and Ireland). Both steaks include a "T"-shaped lumbar vertebrae with sections of abdominal internal oblique muscle on each side. Porterhouse steaks are cut from the rear end of the short loin and thus include more tenderloin steak, along with (on the other side of the bone) a large strip steak. T-bone steaks are cut closer to the front, and contain a smaller section of tenderloin. The smaller portion of a T-bone, when sold alone, is known as a filet mignon, especially if cut from the small forward end of the tenderloin.

There is little agreement among experts on how large the tenderloin must be to differentiate a T-bone steak from porterhouse. The United States Department of Agriculture's Institutional Meat Purchase Specifications state that the tenderloin of a porterhouse must be at least 1.25 inches (32 mm) thick (i.e. measuring from the bone) at its widest, while that of a T-bone must be at least 0.5 inches (13 mm) wide. However, steaks with a large tenderloin are often called a "T-bone" in restaurants and steakhouses despite technically being porterhouse.Owing to their large size and the fact that they contain meat from two of the most prized cuts of beef (the short loin and the tenderloin), T-bone steaks are generally considered one of the highest quality steaks, and prices at steakhouses are accordingly high. Porterhouse steaks are even more highly valued owing to their larger tenderloin.

In the United States, the T-bone has the meat-cutting classification IMPS 1174; the porterhouse is IMPS 1173.

In British usage, followed in the Commonwealth countries, "porterhouse" often means a British sirloin steak (i.e. US strip steak) on the bone, i.e. without the tenderloin on the other side of T-bone. However, nowadays some British on-line butchers also offer American style porterhouse steaks.In New Zealand and Australia, a Porterhouse is striploin steak off the bone.

Thoracic vertebrae

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 vertebrae and they are intermediate in size between the cervical and lumbar vertebrae; they increase in size going towards the lumbar vertebrae, with the lower ones being a lot larger than the upper. They are distinguished by the presence of facets on the sides of the bodies for articulation with the heads of the ribs, as well as facets on the transverse processes of all, except the eleventh and twelfth, for articulation with the 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.

Vertebra

In the vertebrate spinal column, each vertebra is an irregular bone with a complex structure composed of bone and some hyaline cartilage, the proportions of which vary according to the segment of the backbone and the species of vertebrate.

The basic configuration of a vertebra varies; the large part is the body, and the central part is the centrum. 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, 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 conducts for the spinal nerves. The body of the vertebra and the vertebral arch form the vertebral foramen, the larger, central opening that accommodates the spinal canal, which encloses and protects the spinal cord.

Vertebrae articulate with each other to give strength and flexibility to the spinal column, and the shape at their back and front aspects determines the range of movement. Structurally, vertebrae are essentially alike across the vertebrate species, with the greatest difference seen between an aquatic animal and other vertebrate animals. As such, vertebrates take their name from the vertebrae that compose the vertebral column.

Vertebral column

The vertebral column, also known as the backbone or spine, is part of the axial skeleton. The vertebral column is the defining characteristic of a vertebrate in which the notochord (a flexible rod of uniform composition) found in all chordates has been replaced by a segmented series of bone: vertebrae separated by intervertebral discs. The vertebral column houses the spinal canal, a cavity that encloses and protects the spinal cord.

There are about 50,000 species of animals that have a vertebral column. The human vertebral column is one of the most-studied examples.

Vertebrae
Thorax

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