Sphenoid bone

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Bone: Sphenoid bone

Cranial Bones. Only the end of the wing of the sphenoid bone is visible
Image:Gray145.png
Sphenoid bone, upper surface.
Latin	os sphenoidale
Gray's	subject #35 147
MeSH	Sphenoid+Bone

The sphenoid bone (from Greek sphenoeides, "wedgelike") is a bone situated at the base of the skull in front of the temporals and basilar part of the occipital bone.

The sphenoid bone somewhat resembles a butterfly or bat with its wings extended.

1 Portions
2 Named features
3 Additional images
4 See also
5 External links

Portions

It is divided into the following parts:

a median portion, known as the body of sphenoid bone
two greater wings and two lesser wings
Pterygoid processes of the sphenoides which project from it posteriorly (below)

Two sphenoidal conchae are situated at the anterior and posterior part of the body.

Image:Orbital bones.png

Seven bones articulate to form the orbit. The sphenoid bone is one of them, labeled with pink

Named features

Various other named features of the sphenoid bone exist:

pterygoid notch
pterygoid fossa
scaphoid fossa
vaginal process
pterygoid hamulus
pterygoid canal
pterygospinous process

The skull from the front. The sphenoid is labeled with yellow to the left of the picture, both in the orbit and behind the zygomatic process

Additional images

Illu facial bones.jpg Facial bones.	Lateral wall of nasal cavity, showing ethmoid bone in position.	Sphenoid bone visible center right.	Base of skull. Inferior surface.
Lateral view of the skull.	Horizontal section of nasal and orbital cavities.	Floor of the skull.	Roof, floor, and lateral wall of left nasal cavity.

External links

SUNY Figs 22:01-06 - "Lateral view of skull."

v • d • e

Bones of head and neck: the cranium of the skull

Occipital

Squama	external (Inion/External occipital protuberance, Nuchal lines) - planes (Occipital, Nuchal) - internal (Cruciform eminence, Internal occipital protuberance, Sagittal sulcus, Internal occipital crest)
Lateral parts	Condyle (Condyloid fossa, Condylar canal) - Hypoglossal canal - jugular (Jugular process, Jugular tubercle)
Basilar part	Pharyngeal tubercle
Other	Foramen magnum

Parietal

Parietal eminence - Temporal line - Parietal foramen

Frontal

Squama	Frontal suture - Frontal eminence - external (Superciliary arches, Glabella) - foramina (Supraorbital, Cecum) - Zygomatic process - internal (Sagittal sulcus, Frontal crest)
Orbital part	Ethmoidal notch - Lacrimal fossa - Trochlear fovea - Frontal sinus - Frontonasal duct

Temporal

Squama	Articular tubercle - Suprameatal triangle - Mandibular fossa - Petrotympanic fissure - Zygomatic process
Mastoid part	Mastoid foramen - Mastoid process (Mastoid cells) - Mastoid notch - Occipital groove - Sigmoid sulcus - Mastoid antrum (Entrance)
Petrous part	Carotid canal - Facial canal (Hiatus) - Internal auditory meatus - Aqueduct of cochlea - Stylomastoid foramen fossae (Subarcuate fossa, Jugular fossa) - canaliculi (Inferior tympanic, Mastoid) - Styloid process - Petrosquamous suture (note: ossicles in petrous part, but not part of temporal bone)
Tympanic part	Suprameatal spine

Sphenoid

Surfaces	Superior surface: Sella turcica (Dorsum sellae, Tuberculum sellae, Hypophysial fossa, Posterior clinoid processes) - Ethmoidal spine - Chiasmatic groove - Middle clinoid process - Petrosal process - Clivus Lateral surface: Carotid groove - Sphenoidal lingula Anterior surface: Sphenoidal sinuses
Great wings	foramina (Rotundum, Ovale, Vesalii, Spinosum) - Spine - Infratemporal crest - Sulcus for auditory tube
Small wings	Superior orbital fissure - Anterior clinoid process - Optic canal
Pterygoid processes	fossae (Pterygoid, Scaphoid) - pterygoid plates (Lateral, Medial) - Pterygoid canal - Hamulus
Other	Body - Sphenoidal conchae

Ethmoid

Plates	Cribriform plate (Crista galli, Olfactory foramina) - Perpendicular plate
Surfaces	Lateral surface Orbital lamina - Uncinate process Medial surface Superior nasal concha - Superior meatus - Middle nasal concha - Middle meatus
Labyrinth	Ethmoid sinus - ethmoidal foramina (Posterior, Anterior)