Bones of Head/Neck

Question 1

Bones of the Nasal Cavity (lat. wall)

Answer 1

! Ethmoid (sup. and middle. concha are part of ethmoid) 
! Palatine (vertical plate)
! Sphenoid 
! Inferior nasal concha
! Maxilla
! Lacrimal
! Nasal
! Frontal
Floor of Nasal Cavity = hard palate (horz. plate of palatine and maxilla)

Question 2

Function of Nasal Conchae

Answer 2

Increase surface area of nasal mucosa for trapping
particles and warming and humidifying inspired air. Create a turbulence to the air pattern as it passes through the nasal cavity which slows down the velocity of its passage through the nasal cavity (again maximizing the effectiveness of the nasal
mucosa).

Question 3

Bones of Nasal Cavity (sept. wall)

Answer 3

! Ethmoid
! Vomer
! Maxilla
! Palatine
! (Septal cartilage)

Question 4

Meatuses

Answer 4

1) Sphenoethmoidal recess
1 opening: sphenoidal sinus

2) Superior meatus
1 opening: posterior ethmoidal sinus

3) Middle meatus
4 openings:
middle ethmoidal sinus,
anterior ethmoidal sinus,
maxillary sinus (semilunar hiatus)
frontal sinus (via frontonasal duct)
4) Inferior meatus
1 opening: nasolacrimal duct (tears)

Question 5

Larynx

Answer 5

Hyoid bone: C3
• Thyroid cartilage
(superior border):
C4, where
common carotid
bifurcates
• Cricoid cartilage:
C6
• Laryngotracheal
junction: C6–C7

Question 6

Laryngeal Cartilages

Answer 6

• 3 large unpaired cartilages
– Thyroid
– Cricoid
– Epiglottis
• 3 pairs of smaller cartilages
– Arytenoid
– Corniculate
– Cuneiform

Question 7

Circothyroid Cartilage

Answer 7

“Cignet ring”
• Anterior arch
• Posterior lamina
• Ridge for attachment of
esophagus
• Depressions for posterior
crico-arytenoids
• Facets for arytenoid &
thyroid cartilage
articulations

Question 8

Epiglottis

Answer 8

Large, leaf-shaped
cartilage
• Articulates with inner
surface of thyroid angle via
thyro-epliglottic ligament
• Projects postero-superiorly
(up & towards back )
• Upper margin is behind
pharyngeal part of tongue
and connects to it via one
median and two lateral
glossoepiglottic folds

Question 9

Arytenoid Cartilage

Answer 9

Pyramid shaped
• Provide attachment points for vocalis muscle, vestibular
ligament, vocal ligament, posterior and lateral cricoarytenoid
muscles, transverse and oblique arytenoid muscles,
thyroarytenoid muscles
• Articulate with cricoid cartilage & with corniculate cartilages
• Note vocal processes

Question 10

Orbit

Answer 10

1) FRONTAL (roof of orbit)
2) ETHMOID (medial wall)
3) LACRIMAL (medial wall anteriorly - fossa lacrimal sac)
4) GREATER WING OF SPHENOID (lateral border)
5) LESSER WING OF SPHENOID (lateral border)
6) PALATINE (medial wall)
7) MAXILLA (rim of the orbit and floor)
8) ZYGOMATIC (lateral border)

Inferior Oribtal Fissure communicates with ITF

Superior Orbital Fissure communicates with middle cranial fossa along with optic canal

Question 11

Fractures to Orbit

Answer 11

Blow to eye may fracture the orbit – med & inf walls
are VERY thin!

Med wall – ethmoidal sinus

Inf wall – Maxilllary sinus

Sup wall – frontal lobe of the brain