Head and Neck Flashcards
Name the cranial bones that make up the skull.
parietal (2), occipital, frontal, temporal (2), ethmoid (2) and sphenoid (2)
Name the sutures in the skull
Coronal - between frontal and parietal
sagittal - between 2 parietal
lambyoid - between parietal and temporal
what are sutures and why are they relevant at birth
fibrous joints, at birth the bones are unfused to allow them to glide over one another during birth
What is the pterion?
At the squamous temporal bone, where the middle meningeal artery is very superficial, if trauma occurs here, high chance of rupture resulting in extradural haemorrhage
At what level does the common carotid bifurcate?
C4 - internal and external
What percentage of brain blood supply does the internal carotid provide, and what other vessels contribute?
80%, the vestibular arteries provide the rest (branch of external)
Name the branches of the external carotid artery
ascending pharyngeal, superior thyroid, lingual, facial, occipital, maxillary, superficial temporal, posterior auricular
what is the cavernous sinus
a large vein in which several veins from the face drain into, lies near the opic chiasm and eventually drains into the internal jugular vein
what structures run through the cavernous sinus
internal carotid artery, CN III, IX, X & XI
what veins made up the retromandibular vein
the superficial temporal vein and the facial vein
how can infections be passed from the face to internal carotid artery
boils or abcess, get infection into facial vein, this anastomoses with the opthalmic vein which drains into the cavernous sinus. the internal carotid artery runs through the sinus so the infection could get into it
what are the divisions of the trigeminal nerve and what do they supply
a - opthalamic, sensory innervation to forehead, supraoribital, lacrimal
b - maxillary, sensory innervation infraorbital, also to all upper teeth via superior, anterior and middle alveolar nerve
c - mandibular, motor to muscles of mastication and sensory to lower teeth, inferior alveolar nerve
in which position is the TMJ most stable
when the jaw is elevated and teeth occluded
what prevents the jaw from dislocation
the articular tubercle, when the condyle of mandible moves forward, this prevents any further movement
why do you need to be careful when manipulating a dislocated jaw back into position?
dislocation causes stretch on the alveolar nerve and vessels, manipulation in the wrong way could cause further damage
what ligament is the most important in providing stability to the TMJ
the lateral ligament, which is a thickening of the capsule
what divides the neck into the anterior and posterior compartments
the sternocleidomastoid muscle
what muscles lie in the anterior compartment of the neck?
anterior belly of digastric, mylohyoid and infrahyoid muscles (Strap muscles)
what is the clinical role of the pre-tracheal fascia?
It encloses the thyroid gland, when swallowing, this moves up and then back down, allows you to feel the thyroid gland and check for any swelling
what nerves are situated in the anterior neck?
vagus nerve, phrenic nerve and hypoglossal nerve
what muscles are found in the posterior triangle and what nerve supplies these?
sternocleidomastoid and trapezius - both supplied by the accessory nerve - CNXII
name the 5 terminal branches of the brachial plexus.
axillary, radial, musculocutaneous, median, ulnar
How can you decide is facial paralysis is due to a stroke or bell’s palsy?
In a stroke, the forehead is spared, in bell’s palsy it is paralysed
What are the two techniques used to remove a tumour from the parotid gland?
need to dissect out the facial nerve first so it is not damaged. Dissected out in anterograde - the main branch found first then other branches dissected out. Retrograde - smaller branches found and then dissected back to main branch
What nerves innervate the eye muscles?
CN III - superior and medial rectus, inferior oblique
CN IV - superior oblique
CN VI - lateral rectus
Describe innervation of tongue.
Anterior 2/3rds - sensory - trigeminal, taste - facial
Posterior 1/3rd - sensory and taste - glossopharyngeal
What nerves innervate the major salivary glands?
Submandibular and Sublingual - facial
Parotid - glossopharyngeal
