Clivus (anatomy)

Information about Clivus (anatomy)

Bone: Clivus (anatomy)
Superior view of the clivus
Longitudinal section of the head and neck showing the anatomical relation of the dens (labeled odontoid process of axis) and clivus (not labeled).
subject #35 148
Dorlands/Elsevier c_40/12244230
Behind the dorsum sellæ is a shallow depression, the clivus, which slopes obliquely backward, and is continuous with the groove on the basilar portion of the occipital bone; it supports the upper part of the pons.

Relation of the clivus and dens

The clivus is an important landmark for checking for anatomical atlanto-occipital alignment; the clivus, when viewed on a lateral C-spine X-ray, forms a line which, if extended, is known as the known as Wackenheim's clivus line. Wackenheim's clivus line should pass through the dens of the axis or be tangential to it.[1]

See also

References

1. ^ McKenna DA, Roche CJ, Lee KW, Torreggiani WC, Duddalwar VA. Atlanto-occipital dislocation: case report and discussion. Can J Emerg Med 2006; 8(1):50-3. Available at: link and link. Accessed on: December 7, 2006.

External links

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.

 •  • [ e]
Bones of head and neck: the cranium
OccipitalForamen magnum - Squama occipitalis (Inion - Nuchal lines - Planum occipitale - Planum nuchale - Cruciform eminence - Internal occipital protuberance - Sagittal sulcus - Internal occipital crest)
Lateral parts (Occipital condyle - Hypoglossal canal - Condyloid fossa - Condylar canal - Jugular process - Jugular tubercle) - Basilar part (Pharyngeal tubercle)
ParietalParietal eminence - Temporal line - Parietal foramen
FrontalSquama frontalis (Frontal suture - Frontal eminence - Superciliary arches - Glabella - Supraorbital foramen - Zygomatic process - Sagittal sulcus - Frontal crest - Foramen cecum) - Pars orbitalis (Ethmoidal notch - Lacrimal fossa - Trochlear fovea - Posterior ethmoidal foramen - Anterior ethmoidal foramen - Frontal sinus - Frontonasal duct)
TemporalSquama temporalis (Articular tubercle - Suprameatal triangle - Mandibular fossa - Petrotympanic fissure) - Mastoid portion (Mastoid foramen - Mastoid process - Mastoid notch - Occipital groove - Sigmoid sulcus - Mastoid antrum) - Petrous portion (Facial canal - Hiatus of the facial canal - Internal auditory meatus - Subarcuate fossa - Carotid canal - Aqueduct of cochlea - Jugular fossa - Inferior tympanic canaliculus - Mastoid canaliculus - Styloid process - Stylomastoid foramen - Petrosquamous suture) - Tympanic part (Suprameatal spine) - Zygomatic process
SphenoidBody Superior surface (Ethmoidal spine, Chiasmatic groove, Optic foramen, Sella turcica, Fossa hypophyseos, Middle clinoid process, Dorsum sellae, Posterior clinoid processes, Petrosal process, Clivus) - Lateral surface (Carotid groove - Sphenoidal lingula) - Anterior surface (Sphenoidal sinuses) - Great wings (Spine, Foramen rotundum, Foramen ovale, Foramen Vesalii, Foramen spinosum, Infratemporal crest, Sulcus tubae auditivae) - Small wings (Superior orbital fissure, Anterior clinoid process, Optic foramen) - Pterygoid processes (Pterygoid fossa, Scaphoid fossa, Lateral pterygoid plate, Medial pterygoid plate, Pterygoid canal, Pterygoid hamulus) - Sphenoidal conchae
EthmoidCribriform plate (Crista galli) - Perpendicular plate - Labyrinth (Ethmoid sinus) - Lateral surface Lamina papyracea - Uncinate process - Medial surface Middle nasal concha - Superior meatus - Superior nasal concha - Middle meatus
Elsevier, the world's largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. Based in Amsterdam, the company has substantial operations in the UK, USA and elsewhere.
..... Click the link for more information.
dorsum sellæ, ending at its superior angles in two tubercles, the posterior clinoid processes, the size and form of which vary considerably in different individuals.

Additional images



Tentorium cerebelli from above.

..... Click the link for more information.
The occipital bone, a saucer-shaped membrane bone situated at the back and lower part of the cranium, is trapezoid in shape and curved on itself. It is pierced by a large oval aperture, the foramen magnum, through which the cranial cavity communicates with the vertebral canal.
..... Click the link for more information.
The pons (sometimes pons Varolii after Costanzo Varolio) is a structure located on the brain stem. It is rostral to the medulla oblongata, caudal to the midbrain, and ventral to the cerebellum.
..... Click the link for more information.
In vertebrates, cervical vertebrae (singular: vertebra) are those vertebrae immediately behind (caudal to) the skull.

Variation among species

In some species, some parts of the skull may be composed of vertebra-like elements, e.g.
..... Click the link for more information.
X-rays (or Röntgen rays) are a form of electromagnetic radiation with a wavelength in the range of 10 to 0.01 nanometers, corresponding to frequencies in the range 30 PHz to 30 EHz. X-rays are primarily used for diagnostic radiography and crystallography.
..... Click the link for more information.
The dens or odontoid process or odontoid peg of the axis exhibits a slight constriction or neck, where it joins the body.

On its anterior surface is an oval or nearly circular facet for articulation with that on the anterior arch of the atlas.
..... Click the link for more information.
axis (from Latin axis, "axle") or epistropheus.

It forms the pivot upon which the first cervical vertebra (the atlas), which carries the head, rotates.
..... Click the link for more information.
pharyngeal tubercle which gives attachment to the fibrous raphé of the pharynx, also known as the pharyngeal raphe.

This is the point of attachment for the superior pharyngeal constrictor muscle.
..... Click the link for more information.
eMedicine is an online clinical medical knowledge base that was founded in 1996 by Scott Plantz and Richard Lavely, two medical doctors. It was sold to WebMD in January 2006.
..... Click the link for more information.
The State University of New York Health Science Center at Brooklyn, better known as SUNY Downstate Medical Center, is an academic medical center and is the only one of its kind in the Borough of Brooklyn in New York City.
..... Click the link for more information.
Public domain comprises the body of knowledge and innovation (especially creative works such as writing, art, music, and inventions) in relation to which no person or other legal entity can establish or maintain proprietary interests within a particular legal jurisdiction.
..... Click the link for more information.
Henry Gray's Anatomy of the Human Body (or Gray's Anatomy as it has commonly been shortened) is an English-language human anatomy textbook widely regarded as a classic work on the subject.
..... Click the link for more information.
Bones are rigid organs that form part of the endoskeleton of vertebrates. They function to move, support, and protect the various organs of the body, produce red and white blood cells and store minerals.
..... Click the link for more information.
Head and neck anatomy focuses on the structures of the head and neck of the human body, including the brain, bones, muscles, blood vessels, nerves, glands, nose, mouth, teeth, tongue, and throat.
..... Click the link for more information.
skull is normally made up of 22 bones. Except for the mandible, all of the bones of the skull are joined together by sutures, synarthrodial (immovable) joints formed by bony ossification, with Sharpey's fibres permitting some flexibility.
..... Click the link for more information.
The occipital bone, a saucer-shaped membrane bone situated at the back and lower part of the cranium, is trapezoid in shape and curved on itself. It is pierced by a large oval aperture, the foramen magnum, through which the cranial cavity communicates with the vertebral canal.
..... Click the link for more information.
In anatomy, in the occipital bone, the foramen magnum (Latin: 'great hole') is one of the several oval or circular apertures in the base of the skull (the foramina), through which the medulla oblongata (an extension of the spinal cord) enters and exits the skull vault.
..... Click the link for more information.
The squama of the occipital bone, situated above and behind the foramen magnum, is curved from above downward and from side to side.

External surface

The external surface
..... Click the link for more information.
The inion is the most prominent projection of the occipital bone at the lower rear part of the skull. The ligamentum nuchae and trapezius muscle attach to it.

The term external occipital protuberance (protuberantia occipitalis externa
..... Click the link for more information.
The nuchal lines are four curved lines on the external surface of the occipital bone:
  • The upper, often faintly marked, is named the highest nuchal line, and to it the galea aponeurotica is attached.

..... Click the link for more information.
planum occipitale (or occipital plane), and is covered by the Occipitalis muscle.

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated.
..... Click the link for more information.
planum nuchale (or nuchal plane), is rough and irregular for the attachment of several muscles.

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated.
..... Click the link for more information.
cruciform eminence ( or cruciate eminence).
  • The upper two fossae are triangular and lodge the occipital lobes of the cerebrum.
  • The lower two are quadrilateral and accommodate the hemispheres of the cerebellum.

..... Click the link for more information.
internal occipital protuberance.

See also

  • external occipital protuberance

External links

  • Roche Lexicon - illustrated navigator, at Elsevier 34257.000-2
  • Diagram at uni-mainz.

..... Click the link for more information.
sagittal sulcus, the edges of which unite below to form a ridge, the frontal crest; the sulcus lodges the superior sagittal sinus, while its margins and the crest afford attachment to the falx cerebri.

It also is part of the parietal, and occipital bones.
..... Click the link for more information.
internal occipital crest; it bifurcates near the foramen magnum and gives attachment to the falx cerebelli; in the attached margin of this falx is the occipital sinus, which is sometimes duplicated.
..... Click the link for more information.
occipital bone: Foramen magnum | Squama occipitalis (Inion | Nuchal lines | Planum occipitale | Planum nuchale | Internal occipital protuberance | Sagittal sulcus | Internal occipital crest) | Lateral parts (Hypoglossal canal | Condyloid fossa | Condyloid canal | Jugular process |
..... Click the link for more information.
occipital condyles for articulation with the superior facets of the atlas.

The condyles are oval or reniform in shape, and their anterior extremities, directed forward and medialward, are closer together than their posterior, and encroach on the basilar portion of the bone;
..... Click the link for more information.
The hypoglossal canal is a bony canal in the occipital bone of the skull that transmits the hypoglossal nerve from its point of entry near the medulla oblongata to its exit from the base of the skull near the jugular foramen.
..... Click the link for more information.

This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.