The Skull Flashcards
Number of bones in the skull
22
What connects the skull bones?
Fibrous sutures
What is the exception to skull movement?
Temporomandibular joints
Role of skull
Protect the brain, eyes (orbit), nasal cavity structures, oral cavity structures
Visible bones from frontal view of the skull (19)
Frontal bone (1) Parietal bones (2) Temporal bones (2) Sphenoid bone (1) Zygomatic bones (2) Maxilla bones (2) Mandible (1) Lacrimal bones (2) Nasal bones (2) Ethmoid bone (1) Vomer (1) Inferior nasal conchae (2)
Drainage of sphenoid sinus
Into superior meatus
Drainage of ethmoid sinus
Into superior meatus
Drainage of maxillary sinus
Into middle meatus
Drainage of frontal sinus
Into middle meatus
Drainage of nasolacrimal duct
Into inferior meatus
Wide inferior extension of temporal bone
Mastoid process
Attachment of sternocleidomastoid
Thin inferior extension of temporal bone
Styloid process
Hole in temporal bone
External auditory canal (covered by tympanic membrane)
Pterion
Thin area of bone covering the middle meningeal artery which, if perforated, can cause extradural haematoma
Spot of weakness
Area where 4 bones join on lateral skull
Sagittal suture
Joins both parietal bones together
Coronal suture
Joins frontal and parietal bones together
Lambdoid suture
Joins together occipital and parietal bones
Fontanelles
Soft areas between unfused bones in newborns
Differences in newborn skull
Fontanelles
Poorly developed mandible
Short external auditory canal/meatus
Lack of mastoid process
Reasons for fontanelles
Brain growth
Manoeuvrability of skull in childbirth
Cribiform plate
Part of the ethmoid bones
Full of holes
Pituitary fossa
Found in the sphenoid bone on the floor of the skull
Location of the pituitary gland
Sphenoid foramina
Optic canal Superior orbital fissure Foramen rodundum Foramen vale Forale spinarum
Foramen lacerum
Between parietal and sphenoid bones (covered by cartilage in life)
Foramen in parietal
Internal auditory canal
Jugular foramen
For the jugular artery and vein
Between the occipital bone and parietal bone
Occipital foramina
Hypoglossal canal
Foramen magnum
Cranial nerves and their foramina
CN I - Cribiform plate CN II - Optic canal CN III - Superior orbital fissure CN IV - Superior orbital fissure CN V1 - Superior orbital fissure CN V2 - Foramen rotundum CN V3- Foramen ovale CN VI - Superior orbital fissure CN VII - Internal auditory canal CN VIII - Internal auditory canal CN IX - Jugular foramen CN X - Jugular foramen CN XI - Jugular foramen CN XII - Hypoglossal canal Spinal cord - Foramen magnum
Anterior cranial fossa
Contains frontal lobe
Middle cranial fossa
Contains temporal lobe
Posterior cranial fossa
Contains cerebellum and occipital lobes
Hard palate
Comprised of palatine bones (2) and maxilla
Lateral pterygoid plates
Extensions of the ethmoid bone important for mastication
Stylomastoid foramen
Exit of CN VII
Near mastoid process
Carotid canal
In base of temporal? bone
Carotid artery runs through it
Foramen spinosum
Contains middle meningeal artery
