Anatomy: Skull

single: - frontal (develops as paired) - occipital - sphenoid - ethmoid - vomer - mandible (develops as paired) paired: - parietal - temporal - zygomatic - maxillae - nasal - lacrimal - palatine

bones of the cranium: single vs. paired

perpendicular plate of ethmoid bone, vomer

bony nasal septum is made up of which bones

vomer

bony structure of nasal septum

middle meningeal artery

branch of maxillary artery enters middle cranial fossa via the foramen spinosum

diploe

cancellous bone of the skull What is the spongy bone in the skull called?

anterior cranial fossae

cranial fossae: damage to this area will affect: - Frontal lobes of brain, - olfactory bulbs and tracts, - cribriform foramina

middle cranial fossa

cranial fossae: damage to this area will affect: Temporal lobes of brain, pituitary gland, foramina rotundum, ovale and spinosum, superior orbital fissure and optic canals

posterior cranial fossa

cranial fossae: damage to this area will affect: Midbrain, pons and medulla of the brain stem, cerebellum, foramen magnum, jugular foramen, internal acoustic meatus hypoglossal canal, condylar canal and mastoid foramen

glenoid fossa of temporal bone (mandibular fossa)

depression in the temporal bone that articulates with the mandible; part of the temporomandibular joint (TMJ).

foramen spinosum

foramen through which middle meningeal artery enters the skull

hard palate

formed by the palatine processes of the maxillae and the palatine bones posteriorly. function: floor to the nasal cavity and a roof for the oral cavity and an attachment for the soft palate.

perpendicular plate of ethmoid bone

forms superior part of nasal septum

zygomatic bones

known as the cheekbones, articulate with the frontal bone (forehead)

pterion

landmark: middle meningeal artery branches into the large anterior (frontal) branch and small posterior (parietal) branch at the _______

meningeal vessels

lie outside dura mater within deep grooves on inside surface of frontal bone blood supply to dura mater

temporomandibular joint

lies anterior to the ear, the condylar process of the mandible articulates with the inferior surface of the temporal bone

foramen ovale

structures pass through this foramen: - Mandibular nerve. - Accessory meningeal artery - Lesser petrosal nerve, a branch of the glossopharyngeal nerve (preganglionic parasympathetic) - Emissary vein

superior sagittal sulcus

superior sagittal sulcus

sagittal suture

suture between parietal bones

lambdoid suture

suture joint between the occipital bone and parietal bones

mastoid process

the rounded projection on the inferior portion of the temporal bones just posterior to the lobe of the ear insertion of sternocleidomastoid; contains air cells

coronal suture

the suture between the parietal and frontal bones of the skull

petrotympanic fissure

transmits chorda tympani n. (branch of CN VII) and anterior tympanic branch of maxillary a.

foramen rotundum

transmits maxillary division of trigeminal nerve (CN V).

superior orbital fissure

transmits oculomotor nerve (CN III), trochlear nerve (CN IV), abducent nerve (CN VI) and ophthalmic division of trigeminal nerve (CN V).

foramen lacerum location: bigger hole, medial to carotid canal

transmits the greater petrosal nerve

emissary vein

veins that pass through the skull to connect the dural venous sinuses with veins of the scalp; via foramen near sagittal border of parietal bones potential path for spread of infection

crista galli

vertical plate that extends superiorly from the cribriform plate providing attachment for the falx cerebri of the meninges

pharyngeal tubercle

where pharynx is suspended from the base of the skull; attachment of pharyngeal raphe.

pituitary (hypophyseal) fossa

where pituitary gland sits

occipital condyle (occipital bone)

where skull articulates with atlas (C1) function: "yes" bone = allows head to move up and down

zygomatic arch

Bridge-shaped structure that connects the Temporal Bone to the Zygomatic Bone origin of the masseter

carotid groove

Internal carotid artery as it comes out of carotid canal and courses through cavernous sinus

internal acoustic meatus

It is just anterior to jugular foramen in the cranial cavity , which transmits cranial nerves VII and VIII ( facial and vestibulo cochlear nerves)

pterion

Junction of 4 bones: Temporal, sphenoid, parietal and frontal. In the middle of the "temple" Trauma to this area carries a risk of lacerating the middle meningeal artery and causing an epidural hematoma.

greater wing of sphenoid

Lateral orbital wall and roof of infra temporal fossa

frontal sinus

Sinuses above each eyebrow in the frontal bone of the cranium

granular foveolae (arachnoid granulations)

Small projections of the arachnoid membrane through the dura mater into the superior sagittal sinus; CSF flows through them to be reabsorbed into the blood supply.

False (middle and superior nasal conchae are, NOT inferior)

T/F: the inferior nasal conchae is a structure on the ethmoid bone

lambda

The fontanel located at the junction of the lambdoidal and sagittal sutures is called ________. location of the posterior fontanelle in newborn

cribriform plate

The horizontal plate of the ethmoid bone separating the cranial cavity from the nasal cavity. function: openings for olfactory nerves to pass through

bregma

The junction of the sagittal and coronal sutures is the ____; location of anterior fontanelle in newborn

calvaria

The skull cap which is formed by the vaulted frontal, parietal, and occipital bones

internal occipital protuberence

part of occipital bone; midline projection on the internal aspect at the base of the skull; extending bilaterally from this is a sulcus for the transverse venous sinus --> will drain into jugular foramen;

lateral and medial pterygoid process

part of sphenoid bone; serve as the origins of the medial and lateral pterygoid muscles

mastoid process

part of the temporal bone containing hollow air space that surrounds the middle ear; associated with air cells

mastoid foramen

pathway for mastoid emissary vein from sigmoid sinus & meningeal branch of occipital artery potential pathway for infection

foramen for emissary vein

posterior skull

Oblique Line (mandible)

structure of mandible: attachment of buccinator muscle.

Mental Spines or Genial Tubercles

structure of mandible: attachment of genioglossus muscle

Mylohyoid Lines

structure of mandible: attachment of mylohyoid muscle.

coronoid process

structure of mandible: attachment of temporalis muscle.

mandibular foramen

structure of mandible: transmits inferior alveolar nerve and artery.

occipital condyles

structure of occipital bone: lateral to foramen magnum; forms the atlantooccipital joints with the superior articular facets of C1

sella turcica

structure of sphenoid bone contains pituitary fossa for pituitary gland.

optic canal

structure of sphenoid bone transmits optic nerve (CN II) and ophthalmic artery.

Articular Tubercle

structure of temporal bone part of the temporomandibular joint (TMJ).

stylomastoid foramen

structure of temporal bone: transmits facial nerve (CN VII) and stylomastoid artery.

infraorbital foramen

structure of the maxillae: transmits infraorbital nerve and artery.

superior temporal line (contrast: temporalis muscle attaches to inferior temporal line)

structure on frontal and parietal bone: attachment of temporalis fascia

inferior temporal line (contrast: temporalis fascia attaches to superior temporal line)

structure on frontal and parietal bone: attachment of temporalis muscle

supraorbital notch (supraorbital foramen) recall: CN V --> V1 --> frontal n. --> supraorbital n. internal carotid a. --> ophthalmic a. --> supraorbital a.

structure on frontal bone: where supraorbital nerve and artery pass

body of maxillae

structure on maxillae contains the largest paranasal sinus

maxillae

The upper jawbones that assist in the formation of the orbit, the nasal cavity, and the palate and hold the upper teeth.

jugular foramen; CN IX, X, XI

This opening in the skull allows blood to drain from the brain through the internal jugular vein and lets 3 cranial nerves pass through it. What is it?

foramen spinosum

Through which skull foramen does the middle meningeal artery and meningeal nerve pass?

clivus

Where does pons of the brain stem sit?

carotid canal

A canal in the petrous portion of the temporal bone that transmits the internal carotid artery and the internal carotid plexus of sympathetic nerves. location: anterior to jugular foramen (inferior view of skull)

foramen magnum

A large opening at the base of the skull through which the brain connects to the spinal cord.

hypoglossal canal (occipital bone)

Where does the hypoglossal nerve exit the skull?

choroid plexus

CSF continuously secreted by ______

styloid process of temporal bone

Feature of the temporal bones that is the attachment site for hyoid bone ligaments and muscles prone to injury

fontanelles

Fibrous membranes at the angles of cranial bones that accommodate brain growth in the fetus and infant

sutures

________ is the area where cranial bones join together to form immovable joints.

mental foramen

an opening typically between the apices of first and second premolars, allows for entrance of the mental nerve and blood vessels into the mental canal

palatine process

anterior part of hard palate

dens (C2)

articulation of atlas (C1) and axis (C2) bones function: "no" bone = allows head to move side to side when C1-C2 are locked together

internal occipital crest

attachment for falx cerebelli.

inferior nuchal line

attachment of back and neck muscles

superior nuchal line

attachment of back and neck muscles

external occipital protuberence

attachment point for ligamentum nuchae

palatine process of the maxilla

bone forms the hard palate

temporal bones

bone of cranium: paired bones located on the lateral and inferior aspects of skull.

occipital bone

bone of the cranium: forms the posterior part of the calvaria and much of the base of the skull and contains the foramen magnum

frontal bone

bone of the cranium: occupies the anterior end of the skull and forms the forehead and part of the orbits.

parietal bones

bone of the cranium: paired bones that form the lateral and superior parts of the cranium

horizontal plate of palatine bone (pictured), the palatine process of the maxilla

bones form the hard palate

basilar: anterior - pharyngeal tubercle: attachment of pharyngeal raphe condylar: lateral - occipital condyles - hypoglossal canal: transmits CN XII - jugular foramen: transmits CN IX, X, XI, and internal jugular vein - foramen magnum - condylar canal: transmits emissary vein squamous: posterior/superior - internal occipital protuberance: sulcus for transverse venous sinus - external occipital protuberance: attachment point for ligamentum nuchae

list and describe the structures of the occipital bone (hint: relation to foramen magnum)

mandible

lower jaw; not part of the skull developmentally

vertical: medial pterygoid muscle, masseter muscle vs. horizontal: lateral pterygoid muscle

muscles of mastication: ______ = allows the jaw to move in a vertical direction vs. _____ = allows the jaw to move in a horizontal direction

L and R internal carotid arteries L and R vertebral arteries

name the 4 main blood supply to the brain

piriform aperture

opening to nostril or nasal cavity What is the name for the pear shaped opening to the nasal cavity?

orbital process

orbital process of frontal bone makes up that part of the bony cavity of the eyeball