Cranium (info non anatomy)

How many bones in skull? What are they divided into?

22 bones, cranial 8, facial 14

How many cranial bones? What are they subdivided into?

8 bones, calvaria 4, floor 4

What are the Calvaria bones? (Skull cap)

Frontal, occipital, left and right parietal

What are the floor bones?

Ethmoid, sphenoid, left and right temporal

What is the spongy layer between the inner and outer compact bone of the cranial bones?

Diploe

What forms the lambda

The sagittal suture and the lambdoid suture

What forms the bregma?

The sagittal and coronal sutures

What is the squamosal suture between?

Bw the temporal bone and parietal bone

What is the lambdoidal suture between?

The occipital bone and the parietal bone

What is the sagittal suture between?

Bw the two parietal bones

What is the coronal suture between?

The frontal bone and the parietal bones

What junction forms the pterion?

The parietal bone, the squamosal suture, and the greater wing of the sphenoid bone

What forms the junction asterion?

Occipital bone, parietal bone, and the mastoid portion of the temporal bone

What does the parietal bone, squamosal suture, and greater wing of the sphenoid form?

Pterion

What does the occipital bone, parietal bone, and masoid portion of the temporal bone form?

Asterion

What are fontanels?

Incomplete ossification in infant skulls (adult size achieved at 12)

What are the 3 regions the cranial floor is divided into?

Anterior cranial fossa, middle cranial fossa, posterior cranial fossa

how much of the floor is located in the anterior cranial fossa?

From the anterior frontal to the lesser wing of sphenoid

How much of the floor is found in the middle cranial fossa?

From the lesser wings of the sphenoid to the petrous ridges/portion

How much of the floor is found in the posterior cranial fossa

From the petrous ridges/portion to the posterior occipital

What does the anterior cranial fossa house?

The frontal lobes of the cerebrum

What does the middle cranial fossa house?

The temporal lobes

What does the posterior cranial fossa house

The cerebellum, pons, and medulla oblongata

What are the three types of skulls?

Mesocephalic, brachycephalic, and dolichocephalic

What are the measurements for an average skull?

6 × 7 × 9

What is special about a brachycephalic skull?

it’s short from front to back, wide side to side, shallow from vertex to base

What is special about a Dolichocephalic skull?

Long from the front and back, narrow from side to side, deep from vertex to base

What two portions does the frontal lobe have?

vertical (frontal squama) and horizontal portions

what does the frontal squama form?

the forehead and anterior part of cranial vault

what does the frontal bone’s horizonal portions form?

the orbital plates, part of the roof of the nasal cavity, and greater part of the anterior cranial fossa

where is the frontal sinuses contained?

bw two tables of squama on each side of the MSP

what does the frontal sinus articulate with?

left and right parietals (coronal suture) sphenoid (frontosphenoidal suture) ethmoid, nasal bones (frontonasal suture) and zygoma

what is the ethmoid bone consists of?

cuneiform plate, perpendicular plate, labyrinths

what are the labyrinths?

two light, spongy lateral masses part of the ethmoid bone

what processes does the labyrinth have?

superior and middle nasal concha

what is the crista galli

a process of the ethmoid that’s the attachment of the falx cerebri

what does the perpendicular plate form?

superior portion of bony nasal septum of the nose

what does the labyrinths contain?

ethmoidal sinuses divided into the anterior, middle and posterior groups

what does the anterior superior portion of the perpendicular plate articulate with?

sphenoid

what does the anterior inferior portion of the perpendicular plate articulate with?

vomer

what does the posterior superior portion of the perpendicular plate articulate with?

frontal and nasal

what does the posterior inferior portion of the perpendicular plate articulate with?

cartilage of nasal septum

what does the ethmoid bone articulate with

frontal, sphenoid, nasal, lacrimal, maxilla and vomer

what is the parietal eminence tell?

the width of the skull as its the widest point of the head

where is the sphenoid bone located?

base of the cranium anterior to the temporal bones and basilar potion of the occipital bone

what is the sphenoid bone consists of?

body, two lesser wings, two greater wings, two pterygoid processes

What is the horizontal portion of the ethmoid bone called

Cribriform plate

what sinuses are part of the ethmoid

Anterior, middle, and posterior (air cells)

What does the pterygoid processes of the sphenoid articulate with

Palatine and vomer (superiorly with nasal cavity)

What does the body of the sphenoid contain?

2 sphenoid sinuses that are incompletely divided by a median septum

what is the deep depression superiorly on the sphenoid called?

Sella turcica

what does the Sella turcica so?

House pituitary gland

what is the tuberculum sellae?

Anterior boarder of sella (kinda like a wall of Sella turcica)

dorsum Sellae

Posterior border of Sella (kinda like a wall of the Sella turcica)

What is the optic groove?

Groove that’s located on the anterior portion of the tuberculum sellae

what is the optic canal?

Opening underneath the lesser wing

what does the greater and lesser wing of the sphenoid form?

The superior orbital fissure

what foramina are found on the greater wing?

Spinosum, ovale, rotundum (inferior to superior)

What does the pterygoid processes consists of?

Medial and lateral pterygoid laminae

what is the inferior extremity of the medial pterygoid called?

Pterygoid Hamulus

What are the 4 parts of the occipital bone?

Squama, two occipital condyles, basilar portion

what goes through the foramen magnum?

medulla oblongata exits and joins spinal cord

what’s the other name for the inion?

external occipital protuberance

what does the occipital condyles articulate with?

the atlas, forming the occipitoatlantal joints