HNS Flashcards
what is the pterion?
joining of the frontal, sphenoid, parietal and temporal
weak part of skull
middle meningeal artery lies below here –> fracture here can result in epidural haemorrhage
what are the bones in the cranium?
- frontal
- parietal x2
- temporal x2
- sphenoid
- ethmoid
- nasal x2
- maxillary x2
- mandible
- inferior nasal concha x2
- lacrimal x2
- palatine x2
- vomer
what are the contents of the cribriform plate?
olfactory nerve fibres (CN1)
what are the contents of the optic canal?
optic nerve (CN2) opthalmic artery
what are the contents of the superior orbital fissure?
oculomotor nerve (CN3) trochlear nerve (CN4) opthalmic branch of trigeminal (CN 5,1) abducens nerve (CN6) superior opthalmic vein
what are the contents of the foramen rotundum?
maxillary branch of trigeminal nerve (CN5,2)
what are the contents of the foramen ovale?
mandibular branch of trigeminal nerve (CN5,3)
what are the contens of the foramen spinosum?
middle meningeal artery
what are the contents of the carotid canal?
internal carotid artery
what are the contents of the internal acoustic meatus?
facial nerve (CN7) vestibulocochlear nerve (CN8) labyrinthine artery
what are the contents of the jugular foramen?
glossopharyngeal nerve (CN9) Vagus nerve (CN10) Accessory nerve (CN11) sigmoid sinus --> becomes internal jugular vein
what are the contents of the hypoglossal canal?
hypoglossal nerve (CN12)
what are the contents of the foramen magnum?
spinal fibres of accessory nerve (CN11)
inferior portion of medulla
vertebral arteries
anterior and posterior spinal arteries
what are the contents of the stylomastoid foramen?
facial nerve (CN7)
how do you test the sensory functions of the trigeminal nerve?
- ask pt to close eyes and say yes every time they feel the neurotip touch their skin
- touch forehead (V1), just under eye (V2), just next to lip (V3)
- touch on both sides
- ask pt if it felt the same on both sides
how do you test the motor function of the trigeminal?
- ask pt to clench jaw
- palpate masseter anterior to temporomandibular joint
- palpate temporalis muscle over temples (pterion)
- ask if they are in any pain
what are the branches of the facial nerve?
- temproral
- zygomatic
- buccal
- mandibular
- cervical
Two Zebras Bit My Coccyx
how do you test the temporal branch?
raise eyebrows/crease forehead
provide resistance to each movement
how do you test the zygomatic branch?
closing eyes and squeezing them shut
provide resistance to each movement
how do you test the buccal branch?
smile, reveal teeth
provide resistance to each movement
how do you test the mandibular branch?
puff out cheeks
provide resistance to each movement
how do you test the cervical branch?
grimace
provide resistance to each movement
how do you test the glossopharyngeal nerve?
elicit patients gag relfex
what is the physiology of the gag reflex?
sensory limb is mediated by glossopharyngeal nerve –> provides sensation to oropharynx and post 1/3 of tongue
motor limb mediated by vagus
how do you test the motor function of the vagus?
ask pt to open their mouth and say ahhhh
saying this depresses the tongue and makes uvula easier to see
observe elevation of uvula, see if any deviation from midline
in what direction is ulnar deviation?
away from side of lesion
how do you test the motor function of the hypoglossal nerve?
ask pt to stick tongue out
look for any deviation from midline
how do you test the motor function of the accessory nerve?
to test SCM ask pt to look to one side whilst you gently resist movement of head with back of hand
what innervates the superior oblique?
CN 4
what innervates the lateral rectus?
CN 6
what innervates all the other extraocular muscles?
CN 3
what is the primary, secondary and tertiary action of superior oblique?
- depression
- abduction
- medial rotation of eyeball
what is the primary, secondary and tertiary action of inferior oblique?
- elevation
- abduction
- lateral rotation of eyeball
what is the primary function of the medial rectus?
adduction
what is the primary function of lateral rectus?
abduction
what is the primary, secondary and tertiary action of the superior rectus?
- elevation
- adduction
- medial rotation of eyeball
what is the primary, secondary and tertiary action of the inferior rectus?
- depression
- adduction
- lateral rotation of eyeball
how do you exam the extrinsic eye muscles?
H test 30cm in front of pt face
ask pt to keep head still and cover one eye
begin in middle, move finger fully to one side to abduct eye
move up and down and then back to middke
repeat movement to other side to adduct eye
how do you test the ipsilateral and consensual pupillary light reflex?
- shine light into one eye, check ipsilateral shrinking
- move light away from eye for 3 seconds
- shine light into same eye, check consensual shrinking of pupil in other eye
- do on both eyes
what is the afferent pathway for pupillary constriction?
- ganglion cells in eye
- optic nerve
- optic tracts
- pretectal nucleus
- EW nucleus (processing done here)
what is the efferent pathway for pupillary constriction?
- EW nuclei
- PNS fibres along occulomotor nerve
- ciliary ganglion
- PNS fibres along ciliary nerves
- sphincter pupillae –> constriction
how do you carry out the corneal reflex?
place some cotton wool on sclera
produces rapid eye closure to protect eye
what is the afferent pathway of the corneal reflex?
touch sensation sent as impulse along ophthalmic branch of trigeminal nerve
what is the efferent pathway of corneal reflex?
from facial motor nucleus along facial nerve to orbicularis oculi (quickly shutting eye)
what is in each quadrant in a complete adult set of teeth?
x2 incisors x1 canine x2 premolars x3 molars = 8 teeth in each quadrant
what is C7?
vertebrae prominens
what do you feel move up and down with swallowing?
hyoid bone
what is between the superior thyroid cartilage and inferior cricoid cartilage?
laryngeal prominence
where can the lateral mass of the atlas found?
b/ mastoid processes (inferior part of temporal bone) and ramus of mandible (vertical aspect)
what is a cricothyroidotomy?
transverse incision made b/ cricoid and thyroid cartilages
cut into cricothyroid membrane
what is a tracheostomy?
transverse incision made b/ cartilage rings of trachea
palpable below cricoid cartilage
where does the EAM begin and end?
opening of ear canal and ends at tympanic membrane
what instrument is used to look at tympanic membrane?
otoscope
where can you find the carotid pulse?
anterior border of SCM at level of superior border of laryngeal prominence
how do you palpate the cervical lymph nodes?
- always palpate from behind
- move fingers along in circular motions and don’t lift them off the patient
- start below jaw and work posteriorly to submandibular nodes
- then head down anterior border of SCM feeling for paratracheal nodes and ant cervical nodes
- head back along posterior borderof SCM towards pre-auricular nodes
- palpate above ears and back down to post auricular nodes
- move down to posterior cervical nodes
- finally medial to occipital nodes
what is the triangle used for central line access?
- medial, sternal head of SCM
- medial third of clavicle
- lateral, clavicular head of SCM
at which point of the triangle do you insert the needle?
superior apex of triangle
at what angle is the needle inserted?
inserted at 30 degree angle
needle directed towards ipsilateral nipple
why is the R sided jugular preferred?
R internal jugular is wider in diameter and more superficial than L internal jugular vein
easier access
what are the anterior triangle boundaries?
- midline of neck
- inferior border of mandible
- anterior border of SCM
what are the posterior triangle boundaries?
- posterior border of SCM
- anterior border of trapezius
- middle 1/3 of clavicle
what are the contents of the anterior triangle?
- hyoid bone
- common carotid artery
- internal jugular vein
- supra-hyoid muscles (stylohyoid, digastric, mylohyoid, geniohyoid)
- infra-hyoid muscles (omohyoid, sternohyoid, thyrohyoid, sternothyroid)
what are the contents of the posterior triangle?
- external jugular vein
- subclavian vein
- subclavian artery
- trunks of brachial plexus
- phrenic nerve
- vagus nerve
- spinal accessory nerve
where does the internal jugular vein run?
parallel and lateral to common carotid artery
where does the external jugular vein run?
runs from angle of mandible to middle of clavicle
what does the nasal septum consist of?
vomer bone inferiorly
perpendicular plate of the ethmoid bone superiorly
septum cartilage
where does the spinal cord end? what do the nerves continue down as?
ends at L1/L2
nerves continue down individually (cauda equinae)
why does it reduce the risk of damage to do injects below L1/L2?
nerves in cauda equina will displace upon injection
at what spinal levels are injections carried out?
L3/L4
or L4/L5
how do you find the level of L4?
found medially from superior iliac crests
level of L4 is line that joins b/ superior aspects of iliac crests
where would you do injections in children?
sacral injections used into sacral foramina since spinal cord isn’t fully developed
what are subarachnoid injections for? compared to epidurals?
subarachnoid = anaethesia epidurals = analgesia
what does the pedicle of a vertebra do?
connects body of vertebra to arch
what does the lamina of the vertebra do?
connects spinous process with transverse process
describe the levels of flexion/ extension (bending forward and back) in the different sections of the vertebral column
C1-C7: large range
T1-T7: no range
T7-T12: very limited range
L1-S4: large range of motion
describe the levels of lateral flexion (bending side to side) in the different sections of the vertebral column
C1-C7: large range
T1-T7: limited range
T7-T12: large range
L1-S4: limited range
describe the levels of rotation in the different sections of the vertebral column
C1-C7: large range
T1-T7: very limited
T7-T12: large range
L1-S4: no range
describe why the cervix has this range of movement
atlanto-occipital joint and atlanto-axial joint allow full range of movement
describe why the upper thorax has this range of movement
movement is restricted by ribs
flexion/extension is prevented due to long articular processes of vertebra –> prevent vertebrae pivoting on one another
describe why the lower thorax has this range of movement
here ribs are floating
so restrict movement LESS
describe why the lumbo-sacrum has this range of movement
vertebral processes are optimised for flexion/extension
articulations with each vertebra prevent rotation since they are vertical
describe the atlanto-occipital joint
atlas (C1) forms special joint w/ occipital bone
superior articular surfaces of C1 articulate with occipital condyles
joint responsible for flexion/extension of head and neck
YES JOINT
describe the atlanto-axial joint
axis (C2) forms a special joint with atlas
axis has protruding part (dens)
dens articulates with anterior arch of atlas
responsible for lateral rotation of head around neck –> rotating head side to side
NO JOINT
