Unit III - Temporal bone Flashcards
What are the four parts of the temporal bone?
Squamous
Mastoid
Petrous
Tympanic
What are the four parts of the squamous part of the temporal bone?
temporal surface
zygomatic process
mandibular fossa
external auditory meatus
What attaches to the temporal surface of the squamous part of the temporal bone?
temporalis muscle
attachment: temporal fossa –> coronoid process and anterior border (temporal crest) of the ramus of the mandible
function: elevation and retraction (posterior aspect of the muscle) of the mandible
innervation: mandibular n.
blood supply: deep temporal a.
What attaches to the zygomatic process?
Masseter muscle
attachment: zygomatic arch –> angle of mandible and lateral aspect of the mandibular ramus
function: elevation, protraction, and retraction (deep fibers) of the mandible
innervation: mandibular nerve
blood supply: masseteric, facial and transverse facial a.
What are the 5 parts of the mandibular fossa of the squamous part of the temporal bone?
articular eminence and tubercle
petrotympanic fissure
squamotympanic fissure
tegmen tympanii
opening of osseous portion of auditory tube
What is transmitted through the petrotympanic fissure?
chorda tympani n.
what attaches to the squamotympanic fissure?
articular disc
What are the 2 parts of the mastoid part of the temporal bone?
mastoid process
sigmoid sulcus
What attaches to the mastoid process?
(1) sternocleidomastoid
attachment: lateral aspect of mastoid process and superior nuchal line –> manubrium and medial 1/3rd of clavicle
function: flexion of head and neck, and contralateral rotation of the head
innervation: accessory n.
blood supply: occipital, posterior auricular, superior thyroid and suprascapular a.
(2) splenius capitis
attachment: ligamentum nuchae and lower cervical and upper thoracic spinous processes –> lateral third of superior nuchal line
function: extension and lateral flexion of the head
innervation: dorsal rami of cervical spinal n.
blood supply: vertebral, occipital, deep cervical and deep branch of transverse cervical a.
(3) longissimus capitis
attachment: upper thoracic transverse processes –> posterior margin of mastoid process
function: extension and ipsilateral rotation of head
innervation: dorsal rami of spinal n.
blood supply: vertebral, occipital, deep cervical, and deep branch of transverse cervical a.
What are the two parts of the mastoid process?
mastoid notch
occipital groove
What attaches to the mastoid notch?
posterior belly of digastric muscle
attachment: temporal mastoid notch –> intermediate tendon (great cornu of hyoid)
function: depression of mandible or elevation of hyoid
innervation: facial n.
blood supply: occipital and posterior auricular a.
What is the function of the occipital groove?
houses occipital artery
what is the function of the sigmoid sulcus?
houses sigmoid sinus
What are the four parts of the petrous part of the temporal bone?
Anterior surface (trigeminal impression)
Posterior surface (Internal auditory meatus)
Inferior surface (carotid canal, jugular fossa, canaliculus for the tympanic n.)
Superior border (groove for the superior petrosal sinus)
What is the function of the trigeminal impression?
houses trigeminal ganglion
what is the function of the internal auditory meatus?
transmits facial and vestibulocochlear n.
What attaches to the inferior surface of the petrous part of the temporal bone?
levator veli palatini muscle
attachment: petrous temporal bone adjacent to carotid canal and the cartilagenous portion of the auditory tube –> soft palate
function: elevates the soft palate
innervation: vagus nerve (pharyngeal branch)
blood supply: ascending palatine, greater palatine and lesser palatine a.
What is the function of the carotid canal?
transmits the internal carotid artery and carotid nerve
What is the function of the jugular fossa?
transmits the internal jugular vein, glossopharyngeal nerve, vagus nerve, and accessory nerve
What is the function of the canaliculus for the tympanic nerve?
transmits the tympanic nerve
What are the two parts of the tympanic part of the temporal bone?
styloid process
stylomastoid foramen
What attaches to the styloid process of the tympanic part of the temporal bone?
(1) stylohyoid muscle
attachments: styloid process –> greater cornu of hyoid
function: elevation & retraction of hyoid
innervation: facial n.
blood supply: occipital, posterior auricular & facial n.
(2) stylopharyngeus muscle
attachment: styloid process –> posterolateral aspect of pharyngeal wall
function: elevation of pharyngeal wall
innervation: glossopharyngeal n.
blood supply: ascending pharyngeal a.
(3) styloglossus muscle
attachment: styloid process –> lateral base of tongue
function: elevation and retraction of tongue
innervation: hypoglossal n.
blood supply: sublingual a.
(4) stylohyoid ligament
attachment: apex of styloid process –> lesser cornu of hyoid
What is the function of the stylomastoid foramen?
transmits the facial nerve
