Skull, Face, Scalp Flashcards
What are the 2 groups of skull bones?
Viscerocranium and Neurocranium
What is the neurocranium?
cranial bones to protect brain (w/ meninges)
What bones are within the neurocranium?
8 bones
4 singular in midline (frontal, ethmoid, sphenoid, occipital)
2 paired (temporal, parietal)
What is the viscerocranium?
facial bones that support the anterior cranium
Define the mouth, nose, and most of the orbit
The viscerocranium develops from ____
mesenchyme (pharyngeal arches)
What are the bones of the viscerocranium?
15 bones
3 singular in midline (ethmoid, vomer, mandible)
6 paired: maxilla, inferior nasal conchae, zygomatic bones, palatine bones, nasal bones, lacrimal bones
Bones are united via ___
sutures
Sutures are developmentally _____
synchondrosis joints filled with hyaline cartilage
Both maxillae and mandible have _____
alveolar processes (tooth sockets)
Main foramen in the mandible: ____
mental foramen
Main foramen in the maxilla: ____
infraorbital foramen
What are the main features of the mandible?
coronoid process condyloid process (for TMJ) Head, neck, ramus, angle, body Mandibular notch and foramen Mylohyoid groove Mental spines/genial tubercles (superior and inferior)
The frontal bone makes up the ____ of the orbit
roof
The zygomatic bone makes up the ____ of the orbit
lateral wall
The maxilla bone makes up the ____ of the orbit
floor and part of the medial wall
The lacrimal bone makes up the ____ of the orbit
medial wall
The ethmoid bone makes up the ____ of the orbit
medial wall
The sphenoid bone makes up the ____ of the orbit
posterior wall
The medial wall of the orbit is made up by:
maxilla, lacrimal bone, ethmoid bone
What are the main 5 features of the orbit?
supraorbital foramen/notch optic canal (foramen) superior orbital fissure inferior orbital fissure lacrimal groove (nasolacrimal canal)
The supraorbital foramen/notch is located in the _____ of the orbit
superciliary arch
The optic canal (foramen) is located in the _____ of the orbit
medial wall
The superior orbital fissure is located in the _____ of the orbit
medial wall
The inferior orbital fissure is located in the _____ of the orbit
floor
The lacrimal groove (nasolacrimal canal) communicates betweeen what two structures?
between orbit and nasal cavity
What are nasal conchae?
projections from lateral walls in the nasal cavity
What are the 3 major nasal conchae and where are they projecting from?
conchae = turbinate
superior nasal conchae (ethmoid bone)
middle nasal conchae (ethmoid bone)
inferior nasal conchae (separate bone altogether)
What are the 3 fossae in the cranial vault?
What do they each hold?
anterior cranial fossa - holds frontal lobes
middle cranial fossa - holds temporal lobes
posterior cranial fossa - holds cerebellum and brainstem
Paranasal sinuses are spaces within ____
Explain this
spaces within the skull bones
these are internal bony features, so cannot be seen unless cut specifically or in radiographs/xrays
What are some functions of paranasal sinuses?
make bones lighter, adds resonance to voice
Paranasal sinuses are lined by ____
mucousal membrane
Paranasal sinuses are continuous with ____
nasal cavity
What are the paranasal sinuses?
2 frontal sinuses in frontal bone
3-13 ethmoid sinuses in ethmoid bone
2 sphenoid sinuses in sphenoid (can be 2-5)
2 maxillary sinuses in maxilla
What are the layers of the scalp from superficial to deep?
skin, dense connective tissue, aponeurosis, loose connective tissue, pericranium
Describe the skin of the scalp
thin except in occipital region
contain sebacious glands, sweat glands, hair follicles
abundant arterial supply, good venous and lymph drainage
Describe the dense connective tissue of the scalp
forms thick, dense, richly vascularized sub-cutaneous layer with cutaneous nn
Describe the aponeurosis of the scalp
strong, tendinous sheath covering calveria
attachment for frontal/occipital bellies of occipitofrontalis muscle and superior auricular muscle
epicranial aponeurosis aka ___
galea aponeurosis
What is the musculoaponeurotic epicranius?
the muscles and the epicranial aponeurosis of the scalp
What makes up the scalp proper?
skin, dense connective tissue, epicranial aponeurosis
Describe the loose connective tissue of the scalp
Sponge-like layer, potential spaces that may distend with fluid due to injury
allows free movement of scalp proper over underlying calvaria
Describe the pericranium of the scalp
dense layer of connective tissue forms external periosteum of neurocranium which is firmly attached
Describe injury to the dense connective layer of the scalp
bleeding profusely
can quickly lead to fatality
Describe injury to the aponeurotic layer of the scalp
wide gaping of aponeurosis
Describe injury to the loose connective tissue layer of the scalp
DANGER SPACE
infection can spread easily
travels quickly through cranial cavity through EMISSARY VEINS to meninges
fluid can move anteriorly to eyelids and to the roof of the nose
What is the main muscle of the scalp? What is it made up of?
occipitofrontalis muscle
made up of the frontalis m., epicranial aponeurotica (aka galea aponeurotica) and occipitalis m.
What is the action of occipitofrontalis muscle?
moves scalp backwards/forwards
What are the muscles of the ears? What are their actions?
3 auricular muscles
anterior auricular action: protracts ear
superior auricular action: elevates ear
posterior auricular action: retracts ear
Are the auricular muscles superficial or deep?
all 3 auricular muscles (anterior, posterior, superior) are superficial
The face extends from ____ to ____
from forehead –> chin
from ear –> ear
All facial muscles attach to ____
either bone or loose connective tissue
is there deep fascia of the face?
no.
because all facial muscles attach to either bone or connective tissue
all muscles of the face insert on ____
skin!
What are the 3 facial muscles located around the eye?
frontalis muscle
corrugator supercilli muscle
orbicularis oculi muscle
Frontalis muscle
- Where located?
- Action?
forehead
around eyes
action: raise eyebrows “surprise” look
Corrugator supercilli muscle
- Where located?
- Action?
Just superior to eye
*important for botox
action: draws eyebrows in “furrowing”
Orbicularis oculi muscle
- Where located?
- Action?
located around the eye
(has orbital portion and palpebral portion)
action: closes the eye
What are the 3 facial muscles around the nasal region?
procerus muscle, nasalis muscle, levator labii superioris alaeque nasi m.
Procerus muscle
- Where located?
- Action?
vertically oriented muscle on bridge of nose
action: wrinkles bridge of nose
Nasalis muscle
- Where located?
- Action?
two portions: transverse part and alar part
transverse part is located above nostrils
alar part is located just inferior to nostrils
action: compress and dilate the nostrils
Levator labii superioris alaque nasi m
- Action?
dilates nostrils and connects nostrils to upper lip
this is why your upper lip raises when you wrinkle your nose
Orbicularis Oris m
- Where located?
- Action?
SUPERFICIAL M
Located around the mouth
action: closes the mouth
Levator labii superioris m
- Where located?
- Action?
SUPERFICIAL M
Comes straight up off of orbicularis oris towards orbicularis oculi
action: elevates upper lip
Zygomaticus major/minor m
- Where located?
- Action?
SUPERFICIAL M
Zygomatic minor over major
Both come off of orbicularis oris and pass zygomatic arch
Major is much broader than minor
action: draws mouth upward
Risorius muscle
- Where located?
- Action?
SUPERFICIAL M
Comes off of commissure of mouth heading posterior
retracts corner (commissure of mouth)
Mentalis muscle
- Where located?
- Action?
SUPERFICIAL M
Located at the chin
Most medial facial muscle
Muscle sticks straight out
action protrudes lower lio
Buccinator muscle
- Where located?
- Action?
DEEP M
Located coming laterally out from mouth heading posterior
Action: compresses cheek and assists with mastication
Levator anguli oris m
- Where located?
- Action?
elevates angle of the mouth
located at commissure of mouth heading superiorly
What are the 4 muscles of mastication?
temporalis muscle, masseter muscle, medial pterygoid muscle, lateral pterygoid muscle
Temporalis muscle action
elevates and retracts mandible
Masseter muscle action
elevates and clenches mandible
Medial pterygoid muscle action
elevates, protracts and rotates mandible
Lateral pterygoid muscle action
protrudes and rotates mandible
Describe the insertion points of medial pterygoid muscle vs lateral pterygoid muscle
both are relatively medial or lateral on the LATERAL PTERYGOID PLATE
Trigeminal supplies _____ (sensory/motor) innervation to ____ (area)
sensory to face and anterior scalp
Cervical nerve (C2-3) supplies _____ (sensory/motor) innervation to ____ (area)
sensory to back/head, ears, jaw
Facial nerve supplies _____ (sensory/motor) innervation to ____ (area)
motor to mm of facial expression
Mandibular CN V3 supplies _____ (sensory/motor) innervation to ____ (area)
motor to mm of mastication
What are the branches off of CN V1? Where do they innervate?
OPTHALMIC BRANCHES:
- supraorbital (central forehead)
- supratrochlear (medial forehead)
- infratrochlear (upper nose)
- external nasal (lower nose)
- lacrimal n (lateral brow)
What are the branches of CN V2? Where do they innervate?
MAXILLARY BRANCHES:
- zygomaticotemporal nerve (temple)
- zygomaticofacial nerve (upper cheek)
- infraorbital nerve (maxilla/upper lip)
What are the branches of CN V3? Where do they innervate?
MANDIBULAR BRANCHES:
- auriculotemporal nerve (ear, temple)
- buccal nerve (lower cheek)
- mental nerve (chin/lower ilp)
Where is the parotid gland located?
anterior/inferior to ear
What is the action of the parotid duct?
to transmit saliva from gland
Parotid duct aka ____
stensen’s duct
Parotid duct crosses ___ muscle, 1-2cm below ____
crosses masseter muscle, 1-2cm below zygomatic arch
After crossing masseter muscle, parotid duct turns __ degrees and pierces ____
turns 90degrees to pierce buccinator muscle
Parotid duct opens in what location?
in oral cavity opposite 2nd molar
The opening of stensen’s duct is marked by ____
parotid papillae
Any inflammation of the parotid duct is extremely painful. Why?
because connective tissue is continuous with deep cervical fascia
Describe calculus formation in the parotid gland?
stones in the gland are associated with chronic parotiditis
can occur in all 3 salivary glands (submandibular is most likely)
Describe salivary fistulas
openings
most can close spontaneously
but some need a duct ligation
Describe a neoplasm as it relates to parotid gland/duct
neoplasm = abnormal growth of tissue as in cancer
85-90% of mixed tumors are involved with the parotid
gland
Describe Frey’s Syndrome
GUSTATORY SWEATING
sweating is thru sympathetic innervation
salivating is through parasympathetic innervation
following surgery, nerves try to reorganize themselves and mess up so instead of salivating, you sweat
Main trunk of CN 7 enters ___ and bifurcates into….
partoid gland
bifurcates into SUPERIOR TEMPORAFACIAL NERVE and INFERIOR CERVICOFACIAL NERVE
CN 7 gives rise to….
what do these branches innervate?
- temporal nerve (superior to temples)
- zygomatic nerve (inferior to arch)
- buccal nerve (medial to buccinator)
- mandibular nerve (along inferior mandible)
- cervical nerve (inferior to platysma muscle)
- posteror auricular nerve (posterior to lower ear)
The facial nerve can be inflamed at what foramen?
stylomastoid foramen
Inflammation of the facial nerve can be caused by what?
edema and compression of nerve in facial canal
Describe bell’s palsy
most common non-traumatic cause of facial paralysis
The buccal fat pad is located anterior to what muscle?
masseter muscle
Buccal fat pad covers ___ muscle medially
buccinator
Buccal fat pad protects ____
parotid duct and buccal branch of cranial nerve 7
What helps give cheeks “fuller” appearance
buccal fat pad
What are the 2 “buccal nerves”?
buccal nerve of CN 7
buccal nerve of CN 5
What does buccal nerve from CN 7 supply?
MOTOR innervation to buccinator muscle
buccal branch of CN 7 travels lateral to what muscle?
masseter muscle
What does buccal branch of CN V3 supply?
SENSORY innervation to buccal mucosa/skin of cheek
Buccal branch of CN V3 pierces ____
buccinator muscle BUT DOES NOT SUPPLY IT
Long buccal nerve aka ____
buccal branch of CN V3
Superficial temporal artery is a branch of _____
external carotid artery
Superficial temporal vein drains into ___
retromandibular vein
Superficial temporal artery/vein run anterior to ____ towards the ___ region
anterior to ear towards the temporal region
Superficial temporal artery/vein travel with what nerve?
auriculotemporal nerve
Transverse facial artery/vein are branches off of _____ vessels
superficial temporal vessels
Transverse facial vessels cross over masseter muscle between what 2 structures
zygomatic arch and parotid duct
Transverse facial vessels supply blood to what regions?
upper cheek region (parotid gland, duct, masseter muscle)
Facial artery runs ___ to facial vein
anterior
Facial vessels both cross ____
mandible and anterior border of masseter muscle
Where can facial artery be palpated easily?
at anterior mandible of masseter muscle