Prac 2: Anatomy of External Skull Flashcards

1
Q

Excluding the 32 teeth and 6 auditory ossicles, how many bones are in the skull?

A

22

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What types of joints exist between bones of the skull?

A

All fibrous (sutures) -> which ossify in adults over a variable amount of time

Aside from auditory ossicles, the only non-fibrous joint is the Temporomandibular Joint (TMJ) = Bilateral synovial hinge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What portion is the neurocranium?

A

The portion surrounding the brain - more dorsal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What portion is the facial skeleton?

A

Anterior and lower portions of the skull

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

List the facial bones. Which ones aren’t paired?

A
Mandible (unpaired)
Vomer (unpaired)
Maxilla (2)
Zygomatic (2)
Lacrimal (2) 
Nasal (2)
Inferior Nasal Concha (2)
Palatine (2)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Bones of the neurocranium are?

A

Frontal, Occipital, Parietal (2), Temporal (2), Sphenoid and Ethmoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the two divisions of the neurocranium?

A

Calvaria (skull cap)

Cranial Base: Cranial base further divided into Anterior, Middle and Posterior Fossae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Coronal suture - between which bones?

A

Frontal and Parietal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Lambdoid Suture?

A

Parietal and Occipital

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Sagittal Suture?

A

Between the 2 parietal bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Squamosal Suture?

A

Arches posteriorly from the pterion, from the temporal squama to the lower border of parietal bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the Lambda?

A

Meeting of the sagittal and lambdoid sutures

thus meeting of the two parietal bones and occipittal bone, posteriorly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the Bregma?

A

Meeting of the Sagittal and Coronal sutures

thus of frontal bone and parietal bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the vertex?

A

Highest point of the skull

Formed by 4 bones: Frontal, 2 parietals and the occipital

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the Pterion?

A

Short suture on the lateral side of the skull where the greater wing of the sphenoid articulates with 3 other bones:

  • Temporal (squamous part)
  • Frontal
  • Parietal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the asterion?

A

At the articulations of the Parietal, Occipital and Temporal Bones - posterolaterally

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the nasion?

A

Meeting of the nasal and frontal bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the inion?

A

The most prominent part of the external occipital protuberance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the articulating portions involved in the TMJ?

A

The head of the condylar proces of mandible
with
Mandibular fossa of temporal bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

By what type of joint are the teeth attached to the mandible and maxilla?

A

Gomphoses - fibrous peg-in-socket joints

From teeth to the inferior (mandible) and superior (maxilla) alveolar processes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where is the mandibular foramen located? Where does it lead?

A

Medial aspect of the ramus of mandible

Leads into mandibular canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which nerves and blood vessels are transmitted in the mandibular canal?

A

Inferior Alveolar Nerve (from V3)

Inferior Alveolar Artery and Vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where is the mental foramen located?

What emerges from here?

A

Anterolateral aspect of the mandible

Mental nerve and blood vessels (from the mental canal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the superior nuchal line?

A

Extends laterally from the external occipital protuberance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What muscle attaches to the mastoid process of the temporal bone?

A

The sternocleinomastoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Where is the mastoid notch? Which muscle attaches here?

A

Just medial to the mastoid process

Posterior belly of digastric muscle attaches here

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the two parts of the zygomatic bone? With which bones do they articulate?

A
Frontal Process (superiorly) -> with fronal bone
Temporal process (posteriorly) -> with temporal bones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What structures form the zygomatic arch?

A

Temporal process of the zygomatic and the zygomatic process of the temporal bone

29
Q

What is the area above the zygomatic arch?

What is the area below?

A

Temporal Fossa

Infratemporal fossa

30
Q

Describe the location of the infratemporal fossa

A

Beneath the zygomatic arch,

deep to the ramus of the mandible

31
Q

What bones form the anterior opening of the nasal cavity (piriform aperture)?

A

Maxilla (most)

Nasal bones

32
Q

What is the sharp projection of the maxilla at the piriform aperture called?

A

Anterior Nasal Spine

33
Q

Where is the Lateral Pterygoid Plate located? Which bone does it belong to?

A

In the infratemporal fossa, posterior to the maxilla

Part of sphenoid bone

34
Q

Where is the pterygomaxillary fissure?

A

Between the Lateral Pterygoid Plate (in infratemporal fossa, posterior to maxilla) and the Maxilla bone

35
Q

Where is the Pterygomaxillary fossa?

A

Located deeply, at the superior end of the Pterygomaxillary fissure (between maxilla and lateral pterygoid plate)

36
Q

What is Fossa of the Lacrimal Sac?

A

Large depression at the anterior part of the medial wall of the orbit

This opens into the Nasolacrimal Canal -> leads to the nasal cavity

37
Q

Infraorbital foramen - which nerve traverses this?

A

Infraorbital Nerve -> of maxillary division of trigeminal

38
Q

Supraorbital Foramen - which nerve traverses this?

A

Supraorbital Nerve -> from Frontal Nerve of Opthalmic nerve from Trigeminal Nerve

39
Q

Where is the apex of the orbit?

A

Losated Posteriorly/medially on the orbit

40
Q

Where is the superior orbital fissure?

A

In apex of the orbit

41
Q

What nerves and vessels pass through the superior orbital fissure?

(hint think nerves to muscles of eye movement…)

A

CNIII
CNIV
Branches of Opthalmic Nerve (CNV)
CNVI

Sympathetic Fibres from the Cavernous Plexus

Inferior Division of the Opthalmic Vein (also passes through the inferior orbital fissure)

42
Q

Where is the optic canal located?

What nerve and vessel pass through here?

A

Just medial/superior to the superior orbital fissure

Optic Nerve (CNIII)
Opthalmic Artery
43
Q

What passes through the inferior orbital fissure?

A

Zygomatic branch of maxillary nerve

44
Q

What bones contribute to the nasal septum?

A

Inferiorly, the VOMER bone articulates with the Anterior Nasal Spine (of the maxilla).

Superiorly, the nasal septum is formed by the PERPENDICULAR PLATE OF ETHMOID BONE

Septal cartilage fills the triangular space between these bones

45
Q

Middle nasal concha is part of which bone?

A

Ethmoid

46
Q

Roof of nasal cavity is formed by…?

A

Cribriform plate of ethmoid bone

47
Q

What nerve passes through the foramina in the cribriform plate?

A

Olfactory Nerve CNI

48
Q

What forms the base of the nasal cavity?

A

Anteriorly: Palatine Process of Maxilla

Posteriorly: Horizontal Plate of the Palatine bone

49
Q

What specific part of the CNS passes through the Foramen Magnum?

A

Where the medulla is continuous with the spinal cord

50
Q

What major arteries, and which CN enter the skull through the foramen magnum?

A

Vertebral Arteries
Posterior and Anterior Spinal Arteries
Accessory Nerve CNXI

51
Q

What is the Basion?

What is its significance?

A

The most anterior part of the foramen magnum

A landmark to emasure cranial height: from basion to bregma

52
Q

What are the occipital condyles?

A

The point of articulation of the skull onto the 1st cervical vertebra (atlas)

53
Q

Where is the hypoglossal canal, and what passes through it?

A

Superior to the occipital condyles

Hypoglossal nerve (CNXII)

54
Q

Where is the condylar canal?

A

May be present posterior to the occipital condyle

55
Q

Which bones contribute to the Clivus?

A

Clivus = anterior to foramen magnum
Formed from:
Occipital bone anterior to the foramen magnum
Posterior part of the body of sphenoid

56
Q

What is the Foramen Lacerum?

A

Located lateral to the anterior part of the Clivus

Formed at the junction between the Occipital, Temporal (apex of petrous part) and sphenoid bones.

Filled with cartilage in life*

57
Q

What nerve passes through the stylomastoid foramen?

A

Facial Nerve

also the stylomastoid artery

58
Q

What bones contribute to the jugular foramen

What vessel and nerves pass through it?

A

occipital and temporal

Internal Jugular vein
Meningeal Branches from Occipital and Pharyngeal Arteries

Glossopharyngral, Vagus and Accessory Nerves

59
Q

What passes through the carotid canal?

Where is it?

A

Internal carotid artery

Just anterior to the jugular foramen

60
Q

What bone (and part of that bone) forms the lateral walls of the posterior nasal apertures?

A

Medial Pterygoid Plates of the Sphenoid Bone

61
Q

What passes through the foramen ovale?

A

Mandibular division of trigeminal nerve (CNV3)

62
Q

What passes through foramen spinosum?

What artery is this a branch of?

A

Middle Meningeal Artery

from maxillary artery, which is from external carotid artery

63
Q

What is a Metopic Suture?

A

Failure of the frontal suture to ossify (usually does so by ~4yo).

64
Q

What is a fontanelle?

Why do they occur?

A

Fibrous tissue yet to ossify between bones of the neurocranium

Occur because neurocranium bones develop via intramembranous ossification

65
Q

What is the site of the anterior fontanelle?

A

Bregma in v young children

66
Q

Site of Posterior Fontanelle?

A

Lambda in v young children

67
Q

Site of Sphenoidal Fontanelle

A

Pterion in v young children

68
Q

Site of Mastoid Fontanelle

A

Asterion

69
Q

Which bones contain air sinuses?

A

Ethmoid air cells
Maxillary Sinuses
Frontal Sinuses
Sphenoid Sinuses