Foramen magnum
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Bone: Foramen magnum 
Occipital bone. Inner surface. Gray's subject #31 129 MeSH Foramen+Magnum In anatomy, the foramen magnum (Latin: 'great hole') is a large opening in the occipital bone of the cranium. It 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.
Apart from the transmission of the medulla oblongata and its membranes, the foramen magnum transmits the spinal accessory nerve, vertebral arteries, the anterior and posterior spinal arteries, the membrana tectoria and alar ligaments.
Contents
Importance
In humans, the foramen magnum is farther underneath the head than in other great apes. Thus, in humans, the neck muscles (including the occipitofrontalis muscle) do not need to be as robust in order to hold the head upright. Comparisons of the position of the foramen magnum in early hominid species are useful to determine how comfortable a particular species was when walking on two limbs (bipedalism) rather than four (quadrupedalism)..
Additional images
Occipital bone. Outer surface.
Base of skull. Inferior surface.
Base of the skull. Upper surface.
Human brain dura mater (reflections)See also
External links
- SUNY Figs 22:4b-10
- cranialnerves at The Anatomy Lesson by Wesley Norman (Georgetown University) (XI)
- Roche Lexicon - illustrated navigator, at Elsevier 34257.000-1
This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.
Bones of head and neck: Foramina of the skull (and canals, fissures, meati, and hiati) (TA A02.1.00.053–097, GA 2.178–199) Anterior cranial fossa to Orbit: ethmoidal foramina (anterior, posterior)
to Nasal cavity: olfactory foramina (CN-I) · foramen cecumMiddle cranial fossa to Orbit: optic canal (CN-II) · superior orbital fissure (CN-III,IV,V1,VI)
to Pterygopalatine fossa: foramen rotundum (CN-V2) · pterygoid canal
to Infratemporal fossa: foramen ovale (CN-V3) · foramen spinosum/carotid canal
other: foramen lacerum · hiatus for greater petrosal nerve · hiatus for lesser petrosal nerve · sphenoidal emissary foramenPosterior cranial fossa internal auditory meatus/facial canal/stylomastoid foramen (CN-VII,VIII) · jugular foramen (CN-IX,X,XI) · foramen magnum (CN-XI) · hypoglossal canal (CN-XII) · condylar canal · mastoid foramenOrbit to Nasal cavity: nasolacrimal canal
to Face: supraorbital (notch, foramen) · infraorbital (foramen, groove) · zygomatic foramen (-facial, -temporal)
to Pterygopalatine fossa: inferior orbital fissure
other: Inferior orbital fissure · Fossa for lacrimal sacPterygopalatine fossa to Oral cavity: incisive canals · incisive foramen
to Nasal cavity: Foramen vomerinum · Meatus vomerinus · Fissura vomerina · Hiatus vomerinusOther Categories:- Foramina of the skull
- Musculoskeletal system stubs
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Foramen magnum — Saltar a navegación, búsqueda Foramen magnum es el nombre del orificio mayor situado en la parte pósteroinferior del cráneo (base del cráneo, piso témporo occipital), a través del cual se establece la continuidad del sistema nervioso central… … Wikipedia Español
Foramen magnum — (13) im eröffneten Schädel. Das Gehirn wurde entfernt. Das Foramen magnum (lat., „großes Loch“) oder Großes Hinterhauptloch ist die größte Öffnung an der Schädelbasis und wird vom Hinterhauptbein gebildet. Sein hinterer Mittelpunkt wird als… … Deutsch Wikipedia
Foramen magnum — es el nombre del orificio en la parte inferior del cráneo, a través del cual el extremo de la espina dorsal se inserta en el cerebro. En la evolución del hombre, mientras mas abajo estuviera el foramen magnum, mas erguida era la posicion de la… … Enciclopedia Universal
foramen magnum — [mag′nəm] n. [ModL, large opening] the opening at the base of the skull where the spinal cord merges with the medulla oblongata … English World dictionary
Foramen magnum — Os occipital Vue interne … Wikipédia en Français
Foramen magnum — The large hole at the base of the skull which allows passage of the spinal cord. * * * foramen mag·num mag nəm n the opening in the skull through which the spinal cord passes to become the medulla oblongata * * * [TA] the large opening in the… … Medical dictionary
Foramen magnum — didžioji anga statusas T sritis kaulai atitikmenys: lot. Foramen magnum ryšiai: platesnis terminas – išorinis kaukolės pamatas … Paukščių anatomijos terminai
Foramen magnum — didžioji anga statusas T sritis kaulai atitikmenys: lot. Foramen magnum ryšiai: platesnis terminas – užpakalinė kaukolės duobė … Paukščių anatomijos terminai
Foramen magnum — didžioji anga statusas T sritis gyvūnų anatomija, gyvūnų morfologija atitikmenys: lot. Foramen magnum ryšiai: platesnis terminas – pakauškaulis siauresnis terminas – sprando gumburėlis … Veterinarinės anatomijos, histologijos ir embriologijos terminai
foramen magnum — (ARTHROPODA: Insecta) The opening on the posterior side of the head, giving passage to the internal structures that extend from the head to the thorax; the occipital foramen … Dictionary of invertebrate zoology
