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MRCS A - Anatomy > Head and Neck > Flashcards

Flashcards in Head and Neck Deck (194)
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1
Q

5 embryological parts of brain and what they form?

A
Telencephalon = cerebral hemispheres
Diencephalon = Thalamus and hypothalamus 
Mesencephalon = Midbrain
Metencephalon = Cerebellum and pons
Myelencephalon = Medulla
2
Q

1st pharyngeal arch forms….

A
Muscles = TAMM --> Tensor tympani and palatini, anterior digastric, mylohyoid and masseter. PLUS MUSCLES MASTICATION. 
Bones = Maxilla, meckles cartilage, incus 
Arteries = Maxillary and external carotid 
Nerves = Mandibular
3
Q

2nd pharyngeal arch forms….

A

Muscles = BPPSS = Buccinator, platysma, posterior digastric, stylohyoid, stapedius (also muscles of facial expression).

Bones = Stapes, styloid process, lesser horn + upper body of hyoid. 
Arteries = Inferior branch of superior thyroid, Stapedial
Nerve = facial
4
Q

3rd pharyngeal arch forms…..

A
Muscle = stylopharyngeus
Bones = greater horn and lower body of hyoid
Arteries = Common and internal carotids 
Nerves = Glossopharyngeal 
Endocrine = thymus and inferior parathyroids
5
Q

4th pharyngeal arch forms….

A
Muscles = cricothyroid, all intrinsic muscles of soft palate
Bones = thyroid and epiglottic cartilage 
Arteries = right subclavian and left aortic arch
Nerve = Vagus and superior laryngeal 
Endocrine = superior parathyroids
6
Q

5th pharyngeal arch forms….

A

Nothing in humans

7
Q

6th pharyngeal arch forms….

A
Muscles = intrinsic muscle of larynx except cricothyroid (CRICOTHYOID = VAGUS from 4th ARCH)
Bones = Cricoid, arytenoid and corniculate
Arteries = right pulmonary, left pulmonary + ductus arteriosus 
Nerve = Vagus and recurrent laryngeal
8
Q

Which bone contains zygomatic arch, mastoid process and contains external acoustic meatus?

A

Temporal bone

9
Q

Where does posterior digastric muscle attach to on skull?

A

Mastoid notch

10
Q

In the anterior cranial cavity is frontal crest, what attaches here?

A

Falx cerebri = specialisation of dura mater

11
Q

What sits immediately behind the frontal crest at the tip of the ethmoid bone?

What does it transmit?

A

Foramen caecum at the tip of the ethmoid bone

Transmits emissary veins connecting nasal cavity and superior saggital sinus

12
Q

What bone is below the ethmoid bone in the anterior cranial cavity, and what attaches here?

A

Below ethmoid bone = sphenoid bone

Has anterior clinoid processes = point of attachment for tentorium cerebelli

13
Q

What is tentorium cerebelli?

A

Sheet of dura separating posterior cerebral hemispheres from cerebellum

14
Q

Where do granular foveolae live and what do they do?

A

Sit either side of the groove for superior sagittal sinus, and reabsorb CSF

15
Q

In the middle cranial fossa, what makes up the sella turcica and what does it house?

A

Anterior wall = tuberculum sellae
Posterior wall = Dorsum sellae
Deep central area = hypophyseal fossa

Pituitary gland lives here

16
Q

What sits posterior to the medial part of superior orbital fissure?

What sits posterolateral and medial to this?

A

Foramen rotundum
Posteromedial = foramen lacerum
Posterolateral = Foramen ovale, and just lateral to this = spinosum

17
Q

Where does pituitary develop from?

How is it attached to hypothalamus?

A

Rathkes pouch - dépression in the wall of the pharynx

Linked to hypothalamus via infundibulum

18
Q

Which foramen are in the posterior cranial fossa?

A

Foramen magnum, internal acoustic meatus, jugular foramen, hypoglossal canal

19
Q

Bone and contents of the foramen ovale?

A

Sphenoid bone

OVALE:
Otic canal
V3 = mandibular
Accessory meningeal artery 
Lesser petrosal nerve
Emissary veins
20
Q

Bone and content of foramen spinosum?

A

Sphenoid bone

Middle meningeal artery = branch of maxillary artery
Meningeal branch of mandibular nerve

21
Q

Bone and content of foramen rotundum?

A

Sphenoid bone

V2 - maxillary nerve

22
Q

Bone and content of foramen lacerum?

A

Kind of know as carotid canal - immediately lateral lacerum

Sphenoid bone

Internal carotid artery
Nerve and artery of pterygoid canal

23
Q

Bone and contents of jugular foramen?

A

Temporal bone

Anterior = Inferior petrosal sinus

Intermediate = Glossopharyngeal, vagus and accessory nerves = 9/10/11

Posterior = sigmoid sinus, the meningeal branch of occipital + ascending pharyngeal arteries

24
Q

Bone and contents of foramen magnum?

A

Occipital bone

Anterior and posterior spinal arteries
Vertebral arteries
Medulla oblongata

25
Q

Bone and content of Stylomastoid foramen?

A

Temporal bone

Stylomastoid artery
Facial nerve

26
Q

Bone and content of superior orbital fissure?

A

Sphenoid bone

A ROOST

Abducens nerve
Recurrent middle meningeal
Occulomotor nerve - superior and inferior division
Ophthalmic nerve - Lacrimal, frontal and nasociliary
Superior ophthalmic vein
Trochlear nerve

27
Q

Which cranial nerves have parasympathetic innervation and what do they innervate?

A

1973
3 = occulomtor = pupillary constriction + accommodation
7 = facial = Lacrimal gland, submandibular and sublingual
9 = Glossopharyngeal = parotid
10 = Vagus = heart and abdominal viscera

3, 7 and 9 parasympathetic innervation via head and neck = branches of trigeminal

28
Q

How does olfactory nerve exit cranium?

A

Via cribriform plate of ethmoid bone

29
Q

Where does olfactory bulb lie?

A

in olfactory groove in anterior cranial fossa

30
Q

Course of optic nerve?

A

Enters cranium via optic canal in sphenoid bone
Runs along surface of middle cranial fossa
In middle cranial fossa optic nerves from each side unite = optic chiasm
Medial half then crosses over to contralateral sides, lateral part stays ipsilateral = optic tract

Optic tract travels to lateral geniculate nucleus in thalamus
From LGN divides into upper optic radiation via parietal lobe and lower optic radiation via temporal lobe

Both finish in visual cortex

31
Q

Occulomotor nerve general somatic efferent supply?

A

Inferior, superior and medial rectus
Inferior oblique
Levator palpebrae superioris

32
Q

Occulomotor nerve visceral efferent supply?

A

Sphincter pupillae = pupillary constriction

Cilliary muscles = accommodation

33
Q

Occulomotor nerve path?

A

Exits brainstem anteriorly between midbrain and pons.
Travels in tentorium cerebelli and then passes via lateral wall of cavernous sinus
Exits cranial cavity via superior orbital fissure

34
Q

Occulomotor nerve palsy symptoms?

A

Down and out
Pupil fixed and dilated
Ptosis

35
Q

Trochlear nerve somatic efferent supply, and effect this has if absent?

A

Superior oblique

Vertical diplopia - cannot look down and in, head tilt away from affected side.

36
Q

Trochlear nerve path?

A

Only cranial nerve to exit dorsal aspect of brainstem - midbrain.
Exits between posterior and superior cerebellar arteries
Traverses forward and enters tentorium cerebelli
Travels through lateral wall of cavernous sinus
Exits via superior orbital fissure

37
Q

Trigeminal nerve - origin of the nerve and the sensory + motor root?

A

Trigeminal nerve exits via pons
Sensory root forms large crescenteric ganglion originates in Meckels cave - here the three branches exit
Motor ganglion originates in pons

38
Q

Which branch of trigeminal carries all the motor supply?

A

Mandibular

39
Q

Cranial exit of each branch of trigeminal nerve?

A

Standing room only

Superior orbital fissure = V1
Rotundum = V2
Ovale = V3

40
Q

Route of ophthalmic nerve and supply?

A

Passes laterally in wall of cavernous sinus, to exit via superior orbital fissure

Essentially supplies sensation from anterior scalp to eyes
PURE SENSORY

41
Q

Maxillary nerve route?

A

Passes in lateral wall of cavernous sinus, inferior to ophthalmic nerve
Exits via foramen rotundum and enters pterygopalatine fossa
Here it gives off several branches
Exits pterygopalatine fossa via inferior orbital fissure - becoming inferior orbital nerve

42
Q

Branches of maxillary nerve within the pterygopalatine fossa?

A

Gives off zygomatic nerve, which itself gives off zygomaticofacial and zygomaticotemporal

Posterior superior alveolar nerve = supplies molar teeth

Two ganglionic branches which join with pterygopalatine ganglion

Terminal branch exits fossa via inferior orbital fissure = inferior orbital nerve

43
Q

Maxillary nerve supply?

A

Sensation from lower eyelids to upper lips and mucosa

PURELY SENSORY

44
Q

Mandibular nerve root and branches?

A

Exits via foramen ovale, the motor component also exits here and joins with sensory component soon after

Soon after they join = two branches = small meningeal and nerve to medial pterygoid
Then it divides into anterior and posterior trunks

45
Q

Anterior trunk of mandibular nerve branches + innervation?

A

Buccal - mainly sensory, some motor to lateral pterygoid and temporalis
Masseteric = masseter muscle
Deep temporal = temporalis
Nerve to lateral pterygoid

46
Q

Posterior trunk of mandibular nerves branches + innervation?

A
  1. Auriculotemporal
    - sensory to temple, external ear and auditory meatus, tympanic membrane and TMJ
    - delivers parasymp of CN9 via lesser petrosal nerve. This then joins with V3 to give auriculotemporal to the parotid
  2. Lingual
    - Anterior 2/3rds of tongue and lower oral mucosa
    - Chorda tympani branch of CN7 joins = taste to anterior 2/3rds of tongue + salivary secretions
    If any damage proximal to joining of Chorda tympani, then you wont lose the taste to ant 2/3rds.
  3. Inferior alveolar
    - Small nerve to mylohyoid + Anterior belly digastric.
    Innervates all lower teeth
47
Q

What nerve supplies the angle of the jaw?

A

Greater auricular nerve

48
Q

Abducens nerve supplies what muscle?

Pathology if damage?

A

Lateral rectus

Cannot abduct eye, medial deviation
Lateral diplopia

49
Q

Path of abducens nerve?

A

Exits brainstem between pons and medulla
Passes via anterior wall of cavernous sinus (with ICA)
Passes over petrous bone
Exits via superior orbital fissure

50
Q

Which pharyngeal arch does facial nerve supply?

A

Second

51
Q

Which pharyngeal arch does mandibular nerve supply?

A

First

52
Q

Route of the facial nerve?

A

motor nucleus originates from the pons, sensory from nervus intermedius
Then enters petrous bone via internal acoustic meatus with the vestibulocochlear
Here the motor and sensory combine

Passes superior to vestibule of inner ear
At medial aspect of inner widens, and becomes geniculate ganglion

Exits via the stylomastoid foramen
Then enters the parotid gland to give its 5 terminal branches

53
Q

Branches of the facial nerve and where?

A

As it becomes geniculate ganglion near inner ear = three branches:
Chorda tympani, greater petrosal and nerve to the stapedius

As it exits temporal bone via stylomastoid foramen = 2 branches:
Posterior digastric muscle (also supplies stylohyoid) and posterior auricular nerve (occipital belly of occipitofrontalis).

Enters parotid - Temporal, zygomatic, buccal, marginal mandibular and cervical

54
Q

Buccal branch muscles?

A

ZORB LN

Zygomaticus minor - Elevates upper lip
Orbicularis - Close and tighten lip
Risorius - Aids smile
Buccinator - Pulls corner of mouth back
Levator anguli oris - Pulls angle of mouth up
Nasalis - flares nostrils
55
Q

Branches of mandibular nerve

A

MALIN

Mental
Auriculotemporal
Lingual
Inferior alveolar
Nerve to mylohyoid
56
Q

Route of vestibulocochlear nerve?

A

Exits brainstem at cerebellopontine angle between pons and. medulla at cerebellopontine angle.
Within the pons the vestibular and cochlea components join
Exits cranium at internal acoustic meatus(with the facial nerve).
In distal part of this splits into the V + C components again

57
Q

which pharyngeal arch does the glossopharyngeal come from and which muscle does it innervate?

A

3rd pharyngeal arch = stylopharyngeus

58
Q

Route of the glossopharyngeal nerve?

A

Several nerve roots from medulla
These pass through and join in jugular foramen
Just as it exits jugular foramen it gives off tympanic nerve = enters middle ear and joins tympanic plexus

The lesser petrosal nerve arises from the tympanic plexus – supplies parasympathetic to otic ganglion. This goes on to give the auriculotemporal which is joined by V3 to supply parotid.

59
Q

Course of right vagus nerve ?

A
lateral medulla, jugular foramen. 
Then contained in own dural sheath alongside accessory nerve 
Descends in neck in carotid sheath. 
- Medial to IJV
- Posterior to CC and IC 

Anterior to 1st part of subclavian artery
Passes posterior to lung root
Forms vagal plexus inferiorly
Pass via oesophageal hiatus

60
Q

Course of left vagus nerve?

A
lateral medulla, jugular foramen. 
Then contained in own dural sheath alongside accessory nerve 
Descends in neck in carotid sheath. 
- Medial to IJV
- Posterior to CC and IC 

Passes between subclavian artery and common carotid
Passes posterior to lung root
Forms vagal plexus inferiorly
Pass via oesophageal hiatus

61
Q

What are the superior and inferior cervical cardiac nerves branches of, and what is their root?

A

Vagus

Right they pass posterior to subclavian artery
left superior - passes between aortic arch and trachea
Left inferior - descends with vagus itself

62
Q

Course of right recurrent laryngeal vs left?

A

Right branches off and hooks under subclavian artery, ascending alongside trachea to insert in larynx

Left branches off and hooks under aortic arch, behind ligaments arteriosum and supplies larynx
- Left can be injured in thyroid surgery

63
Q

Why is accessory nerve unique, and what does it innervate?

A

Arises from upper 5 cervical segments

Trapezius and sternocleidomastoid

64
Q

Route of accessory nerve?

A

Arises from upper 5 C-spines, ASCENDS via foramen magnum, moves posteriorly and descends via jugular foramen

Fibres pass over transverse process of atlas = here it is crossed by occipital artery
Then descends medially to styloid process, stylohyoid and posterior belly of digastric

Then enters sternocleidomastoid at upper surface, leaves it posteriorly at midpoint
Travels along surface of levator scapulae
In close proximity to superficial cervical LN’s

65
Q

Hypoglossal nerve route?

A

Arises from pre-oliviary sulcus of medulla
Passes via hypoglossal canal
Lies on the carotid sheath, looping under the occipital artery.
Passes deep to the posterior belly of digastric
Then passes under stylohyoid muscle.

66
Q

Hypoglossal supplies all muscle of tongue except which muscle?

A

Palatoglossus = VAGUS

67
Q

Where does the common carotid bifurcate?

A

level of upper thyroid = C3/4

68
Q

Does the cervical sympathetic chain lie anterior or posterior to the CCA?

A

Posterior

69
Q

Route of the left common carotid vs right?

A

LEFT:
Arises immediately lateral to brachiocephalic direct from aorta.
Brachiocephalic vein passes anteriorly
Inferior thyroid artery posteriorly
It is in contact with trachea, left margin of oesophagus and left recurrent laryngeal

In the neck It runs superiorly, deep to sternocleidomastoid
Enters anterior triangle and the carotid sheath
Sits with vagus and IJV —> IJV = lateral, vagus posterior

At C6 = crossed by omohyoid, and passes anterior to carotid tubercle

At C7 thoracic duct and vertebral artery lie behind it

Right is similar except arises directly from brachiocephalic
No thoracic duct on the right
Crossed by recurrent laryngeal posteriorly

70
Q

What is the route of each vertebral artery?

A

Arises from 1st part of subclavian artery

Enters cranial cavity via foramen magnum, running through foramina of transverse processes of upper 6 cervical vertebrae

Runs posteromedially on axis, and then enters sub occipital triangle and enters vertebral canal.

Lies in subarachnoid space

Ascends on antero-lateral medulla surface

Unites to form basilar artery at base of pons

71
Q

Branches of the vertebral artery?

A

Posterior and anterior spinal arteries

Posterior inferior cerebellar artery

72
Q

Branches of the basilar artery?

A

Caudal to rostral:

  1. Anterior inferior cerebellar
  2. Labyrinthine = accompanies CN7/8 into internal acoustic meatus
  3. Pontine
  4. Superior cerebellar = can be decompressed to treat trigeminal neuralgia
  5. Posterior cerebral = oculomotor + trochlear nerve lies between this and superior cerebellar.
    • Supplies occipital lobe and part of temporal
73
Q

What are your branches of the internal carotid?

A
Anterior cerebral
Middle cerebral = brocas
Posterior communicating 
Anterior choroidal 
Ophthalmic
Meningeal + hypophyseal
74
Q

Nerves at risk during carotid endarterectomy?

A

hypoglossal, greater auricular and superior laryngeal

75
Q

What layer do the dural sinuses lie within?

Valves or not?

A

Between the periosteal layer and meningeal layer of dura mater

No valves

76
Q

Superior sagittal sinus location and path?

A

Superior surface of falx cerebri
Begins at foramen caecum - can receive emissary veins from nasal sinus
Ends posteriorly in confluence of sinuses

77
Q

Inferior sagittal sinus route, what joins with it to form what?

A

Begins at inferior border of falx cerebri
Travels posteriorly to end at anterior edge of tentorium cerebelli where it is joined by great cerebral vein
Becomes straight sinus - continues posteriorly

78
Q

Where does confluence of sinuses lie?

A

Dilated space at internal occipital protuberance

79
Q

What sinus extends laterally from the confluence of sinuses, and what does each one receive?

A

The transverse sinuses

Right receives superior saggital sinus

Left receives straight sinus

80
Q

what do the transverse sinuses become as they leave occipital bone, and in turn what do these become?

A

Become the sigmoid sinus, which becomes the IJV

81
Q

Which sinus sits either side of sella turcia, what does it receive from and which structures pass through it?

A

Cavernous sinus

Receives from - Cerebral, ophthalmic and emissary veins

Structures passing THROUGH = ICA and abducens

Structures in LATERAL WALL = superior to inferior: OTOM

  1. Occulomotor (3)
  2. Trochlear (4)
  3. Ophthalmic (V1)
  4. Maxillary (V2)

Or its just the nerves 3,4,5a/b
Then passing through is nerve 6

82
Q

What drains the cavernous sinus into the sigmoid sinus?

A

Inferior and superior petrosal sinuses

83
Q

Tributaries into the internal jugular vein?

A
Pharyngeal
Common facial
Occipital
Lingual
Superior thyroid
Middle thyroid
External jugular
84
Q

Three layers of the meninges?

A

tough outer layer = dura mater
Delicate inner layer = arachnoid mater
Inner layer firmly attached to brain = Pia mater

85
Q

Are your cranial meninges continuous with the spinal meninges?

A

Yes

Apart from dura mater, which has two layers and only the inner meningeal is continuous through the foramen magnum

86
Q

What are the three dural partitions, where they begin and end and what they separate?

A

Falx cerebri - separates cerebral hemispheres
- Begins anteriorly at frontal crest, joins with tentorium cerebelli posteriorly

Tentorium cerebelli - Separates cerebral hemispheres from cerebellum
- Begins anteriorly at clinoid process for sphenoid bone, finishes posteriorly in groves for transverse sinus

Falx cerebelli - separates cerebellar hemispheres

87
Q

Arterial supply to dura mater In anterior fossa?

A

Anterior meningeal artery = branch of ethmoidal arteries

88
Q

Arterial supply to dura mater in middle cranial fossa?

A

Middle meningeal = branch of maxillary, enters via foramen spinosum

accessory meningeal = small branch of maxillary, enters via foramen ovale

89
Q

Arterial supply to dura mater in posterior cranial fossa?

A

Posterior meningeal = terminal branch of ascending pharyngeal, via jugular foramen
A meningeal branch from ascending pharyngeal also enters via hypoglossal canal

Meningeal branch from occipital via jugular foramen and mastoid foramen

Meningeal branch from vertebral artery via jugular foramen

90
Q

Which pharyngeal arch do all the facial muscle come from, and which nerve supplies them?

How can we classify facial muscles?

A

2nd pharyngeal arch = facial nerve

Orbital, nasal and oral group

91
Q

Muscles not defined as facial muscle but from 2nd pharyngeal arch?

A

Platysma: Tenses skin of neck and moves lower lips down
Origin = below clavicle
Insertion = Medial fibres on mandible, lateral fibres join muscles around mouth

Occipitofrontalis
Frontal belly = anterior covers forehead and attaches to skin of eyebrows
Occipital belly = arises from posteiror aspect of the skull
Moves the scalp and wrinkles forehead
Insertion for both = galea aponeurotica

Occipital belly = posterior auricular nerve

92
Q

Course of salivary duct?

A

Crosses masseter, pierces buccinator, drains adjacent to 2nd upper molar = stensens duct

93
Q

Structures passing through the parotid gland?

A

FEAR

Facial nerve - all branches except mandibular
External carotid artery
Auriculotemporal nerve
Retromandibular vein = superficial temporal and maxillary vein combine

94
Q

Lymphatics and innervation of parotid gland?

A

Lymphatics = deep cervical

Innervation:

Sensory = auriculotemporal

Parasymp:

  • Begins in the inferior salivary nucleus. Exits medulla as CNIX
  • Then forms inferior ganglion. Typmanic nerve leaves this. Forms tympanic plexus.
  • in tympanic plexus in middle ear branches to lesser petrosal –> otic ganglion
  • Post-ganglionic it is via auriculotemporal nerve, where it is joined by V3.
95
Q

Branches of the ophthalmic nerve?

A

Supra-orbital and supra-trochlear nerves:
Exit orbit superiorly to supply upper eyelid, forehead and scalp

Infratrochlear exits orbit medially = innervates medial half of upper eyelid and side of nose

lacrimal nerve = exits orbit laterally = lateral half of upper eyelid

External nasal nerve = anterior nose

96
Q

What is the posterior auricular a branch of, where does it branch and what does it supply?

A

Facial nerve

Branches as the facial nerve passes through stylomastoid foramen, to exit temporal bone

Supplies occipital belly of occipitofrontalis and posterior auricular muscle

97
Q

Arterial supply to the face - four main arteries?

A

Facial artery = branch of external carotid, passes through deep structures of the neck, posterior to submandibular gland.
- terminates at medial eye as angular artery

Transverse facial artery = branch of superficial temporal = terminal branch of external carotid
- Arises within parotid

Maxillary artery = larger terminal branch of external carotid

Ophthalmic artery = Branch of ICA
Three small branches: zygomaticofacial, zygomaticotemporal + dorsal artery

98
Q

Venous drainage of face?

A

Facial vein:

  • Supratrochlear and supraorbital form the angular vein
  • this becomes the facial vein
  • Facial vein lies posterior to facial artery, until it reaches inferior mandible and it passes superficially over the submandibular gland (vs. artery passing posterior)
99
Q

Lacrimal gland innervation?

A

Facial nerve gives off the greater petrosal nerve which goes to the pterygopalatine ganglion
Post-ganglionic = joins with nerve fibres of maxillary nerve to form zygomatic nerve.
This joins with lacrimal nerve to innervate lacrimal gland

100
Q

Vasculature of lacrimal gland?

A

Ophthalmic artery and vein

101
Q

Fissures and foramina of orbit?

A

Superior orbital fissure = A ROOST

Inferior orbital fissure = Maxillary nerve + zygomatic branch, infra-orbital vessels

Optic canal = optic nerve and ophthalmic artery

102
Q

Extrinsic eye muscles - innervation and action, and origin /insertion

A

All occulomotor except SO4 LR6

Levator palpebrae superioris = Elevates upper eyelid
- Origin = lesser wing of sphenoid
Insertion = tarsal plate
- superior branch of occulomotor

Superior rectus = Elevates and adducts eye

  • Origin = Superior part of common tendinous ring
  • Inserts = anterior eyeball superiorly
  • Superior branch of occulomotor

Inferior rectus = depresses eye and adducts

  • origin = inferior common tendinous ring
  • insertion = anterior half of eyeball inferiorly
  • Superior branch of occulomotor

Medial recuts = adducts

  • Origin = medial common tendinous ring
  • insertion = Medial anterior eye
  • inferior branch occulomotor

Inferior oblique = adducts and elevates = up and in

  • origin = medial floor of orbit
  • insertion = outer posterior quadrant of eye
  • inferior occulomotor

LR = abducts

  • Origin = lateral common tendinous ring
  • insertion = lateral anterior eyeball
  • abducens

SO = down and out

  • origin = Body oh sphenoid
  • insertion = posterior puter quadrant
  • trochlear nerve
103
Q

2 intrinsic muscles of the eye?

A

Sphincter pupillae - constricts pupil = occulomotor

Dilator pupillae - dilates pupil = superior cervical ganglion

104
Q

lymphatic drainage of external ear?

A

Lower part = superficial cervical
Upper lateral part = superficial parotid
Medial upper part = mastoid and deep cervical

105
Q

Innervation of external ear?

A

Auriculotemporal, greater auricular ands occipital nerve

106
Q

Layers of tympanic membrane?

A

Externally = stratified squamous epithelium
Then fibrous layer
internally = mucous membrane continuous with middle ear

107
Q

Innervation of tympanic membrane?

A

Inner part = glossopharyngeal nerve

Outer part = Auriculotemporal nerve

108
Q

Order of middle ear bones?

A

Tympanic membrane > malleus (via umbo) > incus > stapes > oval window

109
Q

Which nerve innervates middle ear and clinical relevance?:

A

Glossopharyngeal

Means after tonsillectomy / tonsillitis may get ear pain

110
Q

Does Chorda tympani pass medial or lateral to pars flaccida?

and where does Chorda tympani come from?

A

Medial to pars flaccida

It is a branch of the facial nerve once it widens in the middle ear to become geniculate ganglion

111
Q

How does middle ear communicate with nasopharynx?

A

Pharyngotympanic tube anteriorly

112
Q

Arterial supply of middle ear?

Venous supply?

A

2 arteries:
Tympanic branch of maxillary artery
Mastoid branch of occipital / posterior auricular

Venous = pterygoid plexus and superior petrosal sinus

113
Q

2 muscles of the middle ear, innervation and role?

A

Tensor tympani:

  • mandibular nerve of trigeminal
  • contraction causes the handle of malleus to move medially which tightens tympanic membrane = dampens loud noises

Stapedius:

  • Facial nerve
  • Pulls stapes posteriorly in response to loud noise = prevents excessive oscillation
114
Q

Innervation of inner ear and closely related nerve?

A

Vestibulocochlear
Facial closely related - enters inner ear with it via internal acoustic meatus, where it then enters facial canal and enlarges to become geniculate ganglion
At geniculate it gives off greater petrosal nerve
Then goes on to give off stapedius and then Chorda tympani
Exits skull via stylomastoid foramen.

115
Q

Branches of maxillary artery?

A

First part - sits below auriculotemporal nerve and runs along lower border of lateral pterygoid:

  • Middle meningeal
  • Inferior alveolar
  • Deep auricular, anterior tympanic, accessory meningeal

Second part - Runs underneath ramus of mandible and insertion of temporalis. Runs along superficial surface of lateral pterygoid before passing between two heads:

  • Deep temporal
  • Masseteric
  • Buccal
  • Pterygoid
116
Q

Fascial layers of the neck?

A

Superficial fascia - contains platysma

Pre-vertebral - contains scalene muscles and deep muscles of back
- also extends to form axillary sheath, which covers
brachial plexus and axillary artery

Pre-tracheal fascia - covers oesophagus, trachea and thyroid

Carotid sheath = IJV, ICA / CCA and vagus

117
Q

Superficial drainage of the neck?

What forms retromandibular vein?

A

Via external jugular vein:

Formed from joining of retromandibular and posterior auricular veins
Once formed it travels in superficial fascia
Passes superficial to sternocleidomastoid, passing posterior to it just superior to clavicle
Here it pierces cervical fascia
Passes deep to clavicle and enters subclavian

Retromandibular vein formed from superficial temporal and maxillary veins

118
Q

Borders of anterior triangle of neck + subdivisions of this?

A

Anterior border of sternocleidomastoid
Midline of neck
Inferior border of mandible

Submental, submandibular / digastric, carotid and muscular triangles

119
Q

Border and contents of submental triangle?

A

Anterior belly digastric, hyoid bone and anterior midline

120
Q

Border and contents of submandibular/digastric triangle?

A

Anterior and posterior digastric and inferior mandible

Submandibular nodes and glands, facial vessels and hypoglossal

121
Q

Border and contents of carotid triangle?

A

Anterior sternocleidomastoid, Superior omohyoid and posterior digastric belly

Carotid sheath and ansa cervicalis

122
Q

Border and contents of muscular triangle?

A

Hyoid bone, superior belly of omohyoid + anterior sternocleidomastoid

Strap muscles and external jugular vein

123
Q

Muscles of the anterior triangle can be divided into two groups, and what muscles are in these groups?

A

Suprahyoid = Stylohyoid, digastric, mylohyoid, geniohyoid

Infrahyoid = Thyrohyoid, omohyoid, sternohyoid, sternothyroid (TOSS)

124
Q

Innervation of posterior digastric vs anterior digastric?

A

Posterior = facial nerve branch, as it leaves stylomastoid foramen
Anterior branch = mylohyoid branch of inferior alveolar = mandibular posterior trunk branch

125
Q

External carotid path?

A

Divides at C3/C4 from common carotid
Ascends anterior to internal carotid and posterior to post. belly of digastric and stylohyoid.
Pierces the fascia of parotid gland, and within parotid divides into its 2 terminal branches - maxilla and superficial temporal

126
Q

Branches of external carotid from inferior to superior?

A
Superior thyroid
Ascending pharyngeal
Lingual
Facial
Occipital 
Posterior auricular 
Maxillary 
Superficial temporal
127
Q

Ansa cervicalis - relation to IJV in sheath, what it supplies + how to get to it fascia wise?

A

superficial to IJV in carotid sheath

Supplies infra hyoid muscles except thyrohyoid

Must divide pre-vertebral fascia to expose it

128
Q

When dividing strap muscles to expose a large goitre where must you divide?

A

You most divide them superiorly as the ansa cervicalis enters at the inferior aspect of the muscles

129
Q

Thyroid origin and what structure marks course?

A

Foramen caecum = origin

Thyroglossal duct = path of descent

130
Q

Which fascia surrounds thyroid and parathyroid?

A

Pre-tracheal fascia

Clinically relevant as it is an unforgiving fascia = can form tense haematoma post-thyroid surgery

131
Q

Relations of the thyroid - anteriorly, posteriorly, medial + lateral

A

Anterior = infra hyoid muscles except thyrohyoid, anterior sternocleidomastoid

Posterior = parathyroid glands, anastomosis of superior and inferior thyroid arteries

Medial = trachea, larynx, pharynx, oesophagus, Cricothyroid. Also external and recurrent laryngeal

Lateral = carotid sheath

132
Q

Arterial supply of thyroid?

A

Superior thyroid artery = 1st branch of ECA

Inferior thyroid artery = branch of thyrocervical trunk = branch of subclavian. Enters thyroid at C6
- has inferior branch which supplies lower thyroid and
anastomoses with posterior branch of superior thyroid artery
- Ascending branch supplies parathyroids

thyroid ima - 10% of population, directly from brachiocephalic / aorta

133
Q

Venous supply of thyroid?

A

superior and middle thyroid veins directly to IJV

Inferior thyroid vein to brachiocephalic

134
Q

Embryology of parathyroids?

A

inferior ones from 3rd pharyngeal arch - can be associated with thymus

Superior ones with 4th pharyngeal arch, can be associated with thyroid

135
Q

Vasculature of parathyroids?

How does arterial supply ever the parathyroid?

A

Arterial supply is ascending branch of inferior thyroid.
Enters MEDIALLY

Venous is via thyroid veins

136
Q

Borders of posterior triangle?

A

Posterior sternocleidomastoid
Lateral clavicle
Anterior trapezium

137
Q

Contents of posterior triangle?

A
Muscles = Traps, sterno, splenius capitis and the scalenes
Vessels = thyrocervical trunk, external jugular vein and subclavian 
Nerves = accessory nerve and cervical plexus 
LN's = supraclavicular and occipital
138
Q

Muscles of posterior triangle: Origin, insertion, function and innervation?

A

Trapezius = elevate, adduct and depress scapula

  • Accessory
  • origin = superior nuchal line + spinous processes C7 - T12
  • insertion = Lateral third of clavicle, spine of scapula

Sternocleidomastoid = tilt head ipsilaterally

  • accessory
  • Origin = upper sternum and medial clavicle
  • insertion - Lateral half of nuchal line + lateral mastoid process

Splenius capitus = together draw head back, individually move head ipsilaterally
- posterior rami of cervical nerves
- origin = lower half of ligaments nuchae, spinous process of C7 - T4
Insertion = Mastoid process and skull below nuchal line

Posterior scalene = elevates rib 2

  • Anterior rami of C5-C7
  • Origin = transverse process of C4-C6
  • insertion = rib 2

Middle scalene = elevates rib 1

  • Anterior rami of C3-C7
  • origin = transverse process of C2- C7
  • Insertion = rib 1

Anterior scalene = elevates rib 1

  • Anterior rami of C4 - C7
  • Origin = C3-C6
  • Insertion = Rib 1 and scalene tubercle
139
Q

Vessels of posterior triangle in neck?

A

External jugular vein = joining of retromandibular and posterior auricular

Thyrocervical trunk = branch of subclavian artery = inferior thyroid, suprascapular and transverse cervical
- All pass anterior to anterior scalene

Subclavian:

  • 1st part = ascends to medial border of anterior scalene
  • 2nd part passes between anterior and middle scalene
  • 3rd part = emerges from between the two. Becomes axillary artery at lateral border of first rib.
140
Q

Nerves In posterior triangle of the neck?

LN’s of posterior triangle?

A

Accessory nerve = passes deep to sternocleidomastoid
Cervical plexus from C2-C4 anterior rami

Supraclavicular and occipital

141
Q

Branches of subclavian artery?

A

VITC+D

Vertebral arteries
Internal thoracic 
Thyrocervical trunk 
Costocervical
Dorsal scapular
142
Q

Internal thoracic and costocervical trunk: routes + what are they branches of?

A

branches of subclavian artery

Internal thoracic = Passes posterior to the clavicle, enters thoracic cavity anterior to thoracic transversus muscle

Costocervical:

  • on left arises from 1st part fo subclavian, medial to anterior scalene
  • on right arises from second part
  • both sides it ascends superiorly over dome of lung behind anterior scalene
143
Q

Nerves of the root of the neck and their course?

A

Phrenic:
Passes with. IJV on anterior scalene, then passes deep to deep vertebral fasica
LEFT:
Passes over 1st part of subclavian artery, runs between subclavian artery and vein.
Runs laterally to left subclavian, aortic arch and LV
Then passes anterior to root of lung, piercing diaphragm solo
RIGHT:
Passes over second part of subclavian artery, running between the subclavian artery and vein.
Runs anterior to right vagus and lateral to SVC, to the right of the pericardium.
Passes over right atrium, exiting diaphragm at T8

Recurrent laryngeal = branch of vagus
Right hooks under subclavian artery
Left hooks under aortic arch

Sympathetic trunks

144
Q

What are the 3 Sympathetic trunks of the root of neck and what they supply?

A

Superior cervical ganglion = superior cardiac nerves + surrounds carotid arteries

Middle cervical ganglion = C5 + C6, middle cardiac nerves

Inferior cervical ganglion = C7-T1, plexus around vertebral artery + inferior cardiac nerves

145
Q

Where thoracic duct joins left brachiocephalic what are the three confluences and their drainage?

Right sided equivalent?

A

Left jugular trunk = head and neck
Left subclavian trunk = Left upper limb
Left bronchomediastinal = Left half of thoracic structures

Right side has same confluence but they go directly into brachiocephalic in right

146
Q

Relations of thoracic duct and its route?

A
Anterior = oesophagus
left = thoracic aorta
Right  = azygous vein 

At T5 passes to left of oesophagus, passing behind the carotid sheath but in front of:

  • thyrocervical trunk
  • phrenic
  • vertebral artery
147
Q

Where does pharynx begin an end?

A

Base of skull down to the b beginning of the oesophagus at cricoid cartilage (C6)

148
Q

What separates the oropharynx and laryngopharynx?

A

Epiglottis

149
Q

How do you divide up the two sets of muscles in the pharynx, origin and insertions and their innervation?

A

Constrictor muscles = Circumferential fibres. All insert posteriorly into pharyngeal raphe

  • Superior constrictor = pterygomandibular raphe
  • middle constrictor = hyoid bone
  • inferior constrictor = cricoid and thyroid cartilage

Longitudinal muscles = all elevate pharynx, and all insert into pharyngeal wall

  • Stylopharyngeus = medial styloid process
  • Salpingopharyngeus = inferior to opening of pharyngotympanic tube
  • Palatopharyngeus = Palatine aponeurosis

ALL INNERVATED BY VAGUS, except Stylopharyngeus = glossopharyngeal

150
Q

Sensory supply to pharynx?

A
Nasopharynx = V2
Oropharynx = vagus via pharyngeal plexus
Laryngopharynx = Vagus via superior laryngeal
151
Q

Vasculature of pharynx?

Lymph drainage?

A

superior pharynx = branches of external carotid artery

Inferior pharynx = Pharyngeal branches of inferior thyroid artery from thyrocervical trunk

Venous = Pterygoid plexus

LN’s = deep cervical nodes

152
Q

Tonsils:
Arterial supply?
Venous supply?
LN’s?

A

Tonsillar artery = branch of facial

Venous = its veins pierce the constrictor muscles to join either external palatine or facial veins

LN’s = jugulodigastric and deep cervical

153
Q

Tonsillectomy:
Indications?
What is damaged if haemorrhage?

A

Indications. = suspected malignancy, recurrent tonsillitis, causing sleep apnoea

External palatine vein lies laterally = can be damaged in tonsillectomy

154
Q

Innervation of the laryngeal muscles?

A

All by the recurrent laryngeal, except the Cricothyroid = external laryngeal (branch of superior laryngeal from vagus)

155
Q

Muscles of the larynx - origin and insertion?

A

Posterior cricoarytenoid

  • Origin = Posterior cricoid
  • insertion = muscular process of arytenoid

Lateral cricoarytenoid

  • Origin = Arch of cricoid
  • Insertion = Muscular process of arytenoid

Thyroarytenoid

  • origin = posterior thyroid cartilage
  • insertion = muscular process of arytenoid

Transverse and oblique arytenoids

  • Origin = Arytenoid cartilage
  • insertion = contralateral arytenoid

Vocalis

  • origin = depression in lamina of thyroid cartilage
  • insertion = Vocal ligament/process of arytenoid

Cricothyroid

  • origin = cricoid anterolaterally
  • insertion = inferior and horn of thyroid cartilage
156
Q

Arterial supply of the larynx?

Which one of these is closely related to the internal laryngeal nerve, and where does it pass through?

A

Superior laryngeal artery = branch of superior thyroid artery via external carotid

Inferior laryngeal artery via inferior thyroid artery via thyrocervical trunk

Superior laryngeal nerve is closely related to the internal laryngeal nerve, and together they pierce the thyrohyoid membrane

157
Q

Venous drainage of the larynx?

A

Superior laryngeal vein into superior thyroid vein to IJV

Inferior laryngeal vein into middle thyroid artery into IJV

158
Q

LN’s of larynx?

A

Above vocal cord = deep cervical

Below vocal cord is ones associated with inferior thyroid artery

159
Q

What cell type is inner larynx, and what is vocal cords?

A

Inner larynx = ciliated pseudostratified columnar

Vocal cords = stratified squamous

160
Q

Nerve supply of larynx?

A

Superior laryngeal nerve:

  • Descends medial to ICA and divides into external and internal just above hyoid bone
  • Internal = sensory to vocal cords. Pierces thyrohyoid membrane with superior laryngeal artery
  • External = penetrates inferior constrictor of pharynx. Supplies cricothyroid
161
Q

Arterial supply of the nose?

Venous drainage?

A

Comes from internal carotid = anterior and posterior ethmoidal via ophthalmic artery

External carotid:
Maxillary artery gives Sphenopalatine + greater palatine
Facial gives Superior labial + lateral nasal

Pterygoid plexus, anterior region can also drain via facial vein

162
Q

Route of the arteries to the nose from external carotid?

Route of the arteries to the nose from internal carotid?

A

Sphenopalatine:

  • Branch of maxillary, exits pterygopalatine fossa and enters nasal cavity via sphenopalatine fossa
  • Supplies lateral wall via posterior nasal branch, and medial wall via posterior septal branch

Greater palatine:

  • branch of maxillary within the pterygopalatine fossa
  • enters nasal cavity via incisive canal
  • supplies anterior media part of the wall

Superior labial and lateral ansal:

  • Branch of facial
  • Labial = lips and nose, nasal = external nose

Anterior and posterior ethmoidal:

  • From ophthalmic artery
  • Posterior enters via cribriform plate
  • anterior accompanied anterior ethmoidal nerve along groove of cribriform plate and enters via foramen lateral to cristal galli
163
Q

Which arteries from a major anastomosis in the nose?

A

Sphenopalatine, anterior ethmoidal, greater palatine and superior labial = SAGS

This can be site of major epistaxis

164
Q

Nerve supply to nasal cavity?

Which does the anterior ethmoidal artery travel with?

A

special afferent = olfactory

Maxillary = sensory:

  • Enters via sphenopalatine fossa
  • lateral wall and septum

Ophthalmic = sensation:
- Anterior ethmoidal - travels forward in groove of cribriform plate, enters nasal cavity via foramen lateral to Cristal galli with anterior ethmoidal artery

165
Q

What does the anterior ethmoidal artery terminate as and supply?

A

External nasal nerve = tip of nose

166
Q

Lymphatics of nose?

A
Anterior = submandibular
Posterior = deep cervical
167
Q

Innervation of muscles of tongue?

A

All supplied by hypoglossal EXCEPT Palatoglossus = vagus nerve

168
Q

Veins of the tongue?

A

Dorsal lingual vein:

  • Travels with lingual nerve
  • Deep to hyoglossus, on top of the genioglossus
  • Pass out via aperture of mylohyoid, middle and superior constrictor - to IJV

Deep lingual vein:

  • Passes over external surface of hyoglossus, beneath genioglossus.
  • Travels with hypoglossal nerve
  • Drains into IJV
169
Q

Arteries of the tongue?

A

Main on is lingual artery from external carotid, adjacent to greater horn of hyoid

  • Enters cavity via aperture formed from mylohyoid, superior and middle constrictor
  • Passes deep to hyoglossus
  • Then travels forward between hyoglossus and genioglossus
170
Q

Innervation to the tongue?

A

Sensory:
Anterior 2/3rds = mandibular via lingual
posterior 1/3rd = glossopharyngeal

Taste:
Anterior 2/3rds = facial
Posterior 1/3rd = glossopharyngeal

171
Q

Route of hypoglossal, glossopharyngeal and lingual nerve to the tongue?

A

Hypoglossal:

  • Innervates all muscles except palatoglossus
  • Leaves skull via hypoglossal canal
  • At angle of mandible, arches sharply forwards under occipital artery (sternocleidomastoid branch)
  • Travels superficial to ECA/ICA
  • Follows root of deep lingual vein over the hyoglossus

Glossopharyngeal:

  • Leaves skull via jugular foramen + descends along posterior stylopharyngeus
  • Then slips through aperture created by mylohyoid and middle/superior constrictors
  • Is deep to hyoglossus

Lingual:

  • Passes beneath superior constrictor
  • continues forward and passes under submandibular gland
  • Ascends in tongue on superior hyoglossus
  • Closely related to third molar
172
Q

If you extract the 3rd molar, what nerve may be affected and symptoms?

A

Lingual nerve

Paraesthesia on anterolateral tongue

173
Q

Lymphatics of tongue?

A
Tip = submental
Middle = submandibular

Both then go to deep cervical LN’s.

Anterior = ipsilateral
Posterior = bilateral spread
174
Q

What sits superficial and deep to submandibular gland?

A

Superficial = Facial vein and artery, marginal mandibular nerve + cervical branch of facial, Platysma

Deep = Facial artery below mandible, Lingual and hypoglossal nerve

175
Q

Whats the best access for submandibular gland surgery?

A

3cm below mandible = avoid transection of marginal mandibular nerve

176
Q

Vessels and lymphatics of submandibular gland?

A

Facial artery and vein

LN’s = deep cervical and jugular

177
Q

Parasymp. innervation of submandibular gland?

A

Superior salivary nucleus
Chorda tympani via facial nerve
Joins onto lingual nerve

178
Q

Common cell type found in parathyroids?

A

Oxyphill

179
Q

Arterial and venous supply of the teeth?

A

Arterial = branches of the maxillary artery
Superior alveolar = upper teeth
Inferior alveolar = lower teeth

Venous maps this -> pterygoid plexus

180
Q

Innervation of teeth?

A

Upper teeth = branch of maxillary nerve = Anterior/posterior/middle superior alveolar branches

lower teeth = mandibular nerve = inferior alveolar nerve
- This divides next to first pre-molar into incisive and mental branches

181
Q

Thymus - cellular arrangement?

A

Has cortex = tightly packed lymphocytes

Has medulla = epithelial cells, arranged around keratinised Hassall’s corpuscle

182
Q

Thymus arterial and venous supply?

A

Arterial = Internal mammary + pericardiophrenic

Venous = left brachiocephalic

183
Q

Draw the cranial fossa and the foramen - labelling each one and its contents.

A

See notes.

184
Q

Bones and contents of internal acoustic meatus?

A

Temporal bone

Facial nerve
Vestibulocochlear nerve
Labrynthine artery

185
Q

Bone and contents of optic canal?

A

Sphenoid bone

Optic nerve
Ophthalmic artery

186
Q

How does the facial nerve go via the Internal acoustic meatus AND stylomastoid foramen?

A

Nerve arises In the pons - two roots a motor and sensory.
The two roots travel via the internal acoustic meatus.
Still within the temporal bone they exit the IAM and 3 big things happen:
1. two roots fuse = facial nerve
2. next the nerve forms geniculate ganglion
3. Gives off three branches = greater petrosal, Chorda tympani and nerve to stapedius

Then exits cranium via stylomastoid foramen.

187
Q

Orbital group of face muscles (2)?

A

Orbicularis oculi = close eyelids
Two major parts outer orbital part, inner palpebral part
Origin = medial palpebral ligament
Palpebral part finishes lateral ralphe, orbital part is continual orbit.

Corrugator supercilli = draws eyebrow to midline, wrinkling above nose
Origin = medial end of superciliary arch
Inserts = skin medial half of eyebrow.

188
Q

nasal group of facial muscles (3)

A
  1. nasalis = flares and closes nasal aperture.
    Alar part flares. originates maxilla below, inserts alar cartilage.
    Transverse part decompresses. Origin maxilla, inserts aponeurosis across dorsum of nose
  2. Procerus = brings medial eyebrow down and wrinkles nose.
    Origin = nasal bone
    Inserts skin lower forehead.
  3. Depressor septi nasi = widens nostrils
    Origin = maxilla insertion = lower part of septum.
189
Q

Oral group facial muscles (4)?

A
  1. Orbicularis oris = narrows mouth e.g. whistling
    Origin - buccinator, some maxilla superiorly and mandible inferiorly
    Insertion = ski and mucous membranes of lips
  2. Buccinator = Contracts cheeks against teeth
    Origin = posterior maxilla and mandible
    Insertion. = corner of lips and blends with orbiculares oris
  3. Lower group oral muscles
  4. Upper group oral muscles
190
Q

Muscles of mastication (4)?

What innervates them all?

A
  1. Masseter = elevates mandible
    Origin = zygomatic arch and maxillary process of zygoma
    Inserts = lateral mandible
  2. Temporalis = elevates and retracts mandible
    Origin = bone of temporal fossa
    Insertion = Mandible
  3. Medial pterygoid = elevates and lateral movement of mandible
    Origin = Deep head > medial pterygoid process. Superficial head = tuberosity of maxilla.
    Insertion = medial mandible
  4. Lateral pterygoid = protrusion and lateral mandible movement
    Origin = upper head > infra temporal fossa. Lower head > lateral pterygoid.
    Insertion = TMJ and neck of mandible.

ALL INNERVATED BY MANDIBLE

191
Q

Suprahyoid muscles?

A
  1. Stylohyoid = elevates hyoid bone
    Origin = base of styloid process
    Insertion = lateral hyoid bone
    Facial Nerve
  2. Posterior digastric = pulls hyoid bone up and back
    Origin = mastoid process temporal bone
    Insertion as above
    Facial nerve
  3. Digastric anterior belly = Lowers mandible
    Origin = Lower mandible
    Insertion = tendon of hyoid bone
    Mylohyoid nerve from inferior alveolar of mandibular
  4. Mylohyoid = Elevate floor of mouth
    Origin = mylohyoid line on mandible
    Insertion = body of hyoid bone
    Mylohyoid nerve
  5. Geniohyoid = Elevate hyoid or pull mandible down
    Origin = mandible
    Insertion = Anterior hyoid
    Anterior ramus C1 via CNXII
192
Q

Infrahyoid muscles?

A
  1. Thyrohyoid = depresses hyoid and raises larynx.
    Origin = thyroid cartilage
    Insertion = Body of hyoid
    Anterior ramus C1 via CNNXII
  2. Sternohyoid = Depresses hyoid bone post swallow
    Origin = Posterior SCJ
    Insertion = body of hyoid
    Anterior ramus C1-3 via ansa cervicalis
  3. Omohyoid = depresses hyoid bone
    Origin = superior scapula
    inserts lower body of hyoid
    Anterior rami C1-3 via ansa cervicalis
  4. Sternothyroiud = draws larynx down
    Origin = posterior surface of sternum
    Insertion = thyroid cartilage
    Anterior rami C1-3 via ansa cervicalis
193
Q

Thyrocervical trunk - route and branches?

A

Arises medial to anterior scalene. Gives three branches:

  1. Inferior thyroid = Ascends anterior to anterior scalene, then moves medial and posterior to carotid sheath
    - The it moves medially it gives off ascending cervical and inferior laryngeal arteries
  2. Transverse cervical artery = passes laterally and anterior to anterior scalene
  3. Suprascapular - anterior to anterior scalene
194
Q

What does internal thoracic artery branch off of, and what does it split into?

A

Branch of subclavian artery

As it passes 6th intercostal space it divides into superior epigastric and musculophrenic arteries.