Lecture 1: Skull Flashcards
Name all of the bones in the skull
- Frontal bone
- Temporal bone
- Parietal bone
- Zygomatic bone
- Occipital bone
- Sphenoid bone
- Nasal bone
- Ethmoid bone
- Maxilla
- Mandible
- Vomer
What is this?
Anterior Fontanelle
Found in new-borns
There is a membrane sitting there
The largest fontanelle found at the junction of the sagittal suture, coronal suture, and frontal suture;
(There is also lateral and posterior fontanelle- lateral closes first)
Name the parts of this skull (8)
1) Frontal bone
2) Parietal bone (x2)
3) Occipital bone
4) Coronal suture
5) Lambdoid suture
6) Saggital suture
7) Bregma
8) Lmabda
What is the name of the case where there is a delay in closing of the anterior fontanelle
Cleidocranial dysplasia
Name the parts of the posterior skull
1) Sutural bone
2) Parietal bone
3) Squamous part of the occipital bone
4) Lamboid suture
5) Occipitomastoid suture
6) Saggital suture
7) Inion
8) Sueprior Nuchal line
9) Inferior nuchal line
10) External occiciptal crest
11) Mastoid process
12) Styloid process
Whe the anterior fontanelle closes, it forms the _____
Bregma
What is the name of the case (not disorder) where the posterior fontanelle closes early
Craniosynostosis
What bones make up the Anterior of the Skull?
1) Frontal bone
2) Zygomatic
3) Maxilla
4) Nasal bone
5) Mandible
Label
1) Frontal bone
2) Maxilla
3) Zygomatic
4) Nasal bone
5) Mandible
Label
1) Frontal bone
2) Parietal bone
3) Temporal bone
4) Occipital bone
5) Zygomatic bone
6) Sphenoid
7) Maxilla
8) Nasal bone
9) Mandible
Label
Mastoid process
Where is the mastoid process?
In the temporal bone
Where is the weakest point of the skull?
What is its clinical significance?
Pterion
Where lots of different bones come together
(anterior part of the) Middle menangial artery runs just behind here
Describe the Surface anatomy of the pterion
____See next lecture_____
What are fontanelles?
A fontanelle is an anatomical feature of infant human skull comprising any of the soft membranous gaps/sutures between cranial bones. It should close at the right time (not earlier or later).
- Anterior fontanel: Not fully ossified, membrane exists. Close ~18 months becomes bregma
- Posterior fontanel: Close at ~9months becomes lambda
- Lateral fontanel
Coronal suture: groove for __________ artery.
Sagittal suture: groove for ________ artery.
Coronal suture: groove for anterior branch of middle meningeal artery.
Sagittal suture: groove for middle meningeal artery.
What happens if the pterion is damaged?
Damage the anterior branch of the Middle Meningial artery
Extradural haemorrhage
The intracranial fossa is divided into…….
1) Anterior fossa
2) Middle fossa
3) Posterior fossa
Name the important foramen in the intracranium (Superior)
What is Cleidocranial Dysplasia?
- Cleidocranial Dysplasia s a birth defect that mostly affects the bones and teeth.[1]
- The collarbones are typically either poorly developed or absent, which allows the shoulders to be brought close together.[1]
- The front of the skull often does not close until later, and those affected are often shorter than average.[1]
- Other symptoms may include a prominent forehead, wide set eyes, abnormal teeth, and a flat nose.[1]
- Symptoms vary among people; however, intelligence is typically normal.[1]
delayed closure of anterior fontanelle
What is Craniosynotosis
Clinical: Craniosynostosis
Craniosynostosis is a condition in which one or more of the fibrous sutures in an infant skull prematurely fuses by turning into bone (ossification), thereby changing the growth pattern of the skull. Because the skull cannot expand perpendicular to the fused suture, it compensates by growing more in the direction parallel to the closed sutures
What is a suture?
A suture is a type of fibrous joint, which only occurs in the skull (e.g. coronal suture is formed by the articulation of the frontal (1) and parietal bones (2)).
identify the lambdoid, squamous, sphenoparietal and occipitomastoid sutures on a dry skull.
What are the different areas of the Mandible?
- Ramus of the mandible
- Body of the mandible
- Condyle of the mandible
- Coronoid of the mandible
- Angle of the mandible
Label
A) Body
B) Ramus
C) Condylar Process
D) Coronoid process
E) Mental foramen
F) Madnibular foramen
Label
1) Lingula
2) Mandibular foramen
3) Submandibular fossa
4) Mylohyoid line
5) Sublingual fossa
What is Paget’s Disease?
Paget’s disease
Skull bones getting thicker.
Name the Bones forming the base of the skull. (Inferior view)
Bones forming the base of the skull.
- Hard palate (maxilla)
- Hard palate (palatine bone)
- Zygomatic bone
- Sphenoid bone
- Vomer
- Temporal bone
- Occipital bone
Name 3 bonny processes
Paired bony prominences.
- Mastoid process (posterior belly of digastric muscle attaches to the medial aspect of mastoid process)
- Occipital condyle (the atlas (vertebra CI) articulates with occipital condyle)
- Styloid process
Describe the boudaries AND name the bones forming each fossa.
Anterior Intracranial fossae
Parts of frontal, ethmoid, and sphenoid bones form the anterior cranial fossa.
- Anteriorly border: inner surface of the frontal bone.
- Posteriorly border: anterior border of prechiasmatic sulcus of sphenoid (medial), lesser wings of sphenoid bone (lateral)
- Floor: frontal bone, ethmoid bone and the anterior aspects of the body and lesser wings of the sphenoid bone
Describe the boudaries AND name the bones forming each fossa.
Middle Fossa
The middle cranial fossa consists of parts of the sphenoid and temporal bones
- Anterior border: anterior edge of chiasmatic sulcus of body of sphenoid (midline) and greater wing of sphenoid (laterally).
- Posterior border: posterior edge of dorsum sellae of body of sphenoid (midline) and petrous part of temporal bone (laterally).
- Floor: the body and greater wing of the sphenoid, and the squamous and petrous parts of the temporal bone.
Describe the boudaries AND name the bones forming each fossa.
Posterior fossa
The posterior cranial fossa consists mostly of parts of temporal and occipital bones, with small contributions from sphenoid and parietal bones. It is the largest and deepest of the three cranial fossae and contains the brainstem (midbrain, pons, and medulla) and the cerebellum.
- Anterior border: dorsum sellae of body of sphenoid bone (medial), superior border of petrous part of temporal bone (lateral).
- Posterior border: internal surface of the squamous part of the occipital bone, (petromastoid part of temporal bone and small parts of occipital and parietal bones).
- Floor: mastoid part of the temporal bone and the squamous, condylar and basilar parts of the occipital bone.
Label
1) Foramen rotundum
2) Foramen Ovale
3) Carotid canal
4) Foramen spinosum
5) Jugular foramen
6) Foramen magnum
7) Hypoglossal canal
8) Internal acoustic meatus
9) Foramen lacerum
10) Superior orbital fissure
11) Optic canal
12) Cribiform plate
What structures pass through the base of the extracranial foramina?
- Incisive foramen: nasopalatine nerves and sphenopalatine vessels (artery and vein).
- Greater palatine foramen: greater palatine nerve, greater palatine vessels
- Foramen ovale: V2 (mandibular division of trigeminal)
- Foramen spinosum: middle meningeal artery
- Carotid canal: internal carotid artery
- Jugular foramen: CN IX (glossopharyngeal), X (vagus), XI (accessory), internal jugular vein
- Foramen magnum: spinal cord, vertebral arteries, (root of CN XI), meninges
- Foramen lacerum: closed in life by a cartilaginous plug, and no structures pass through it completely (near internal carotid artery).
- Forman rotundum: V2 (maxillary division of trigeminal)
- Hypoglossal canal: CN XII (hypoglossal)
- Internal acoustic meatus CN V2 (facial), C3 (vestibulocochlear), (labyrinthine a. and v.)
- Optic canal: CN II (optic), ophthalmic a.
- Cribriform plate: CN I (olfactory)
- Superior orbital fissure: V1 (Ophthalmic division of trigeminal), III (Oculomotor), IV (Trochlear), VI (Abducent), superior opthalmic vein
Label
1) Incisive fossa
2) Greater platine foramen
3) Formane Ovale
4) Foramen spinosum
5) Carotid canal
6) Jugular foramen
7) Foramen Magnum
Name the Extracranial foramina and structures passing through it
1) Incisive fossa
- Nasopalatine nerve
- Sphenopalatine vessles
2) Greater platine foramen
- Greater palatine nerve and vessles
3) Formane Ovale
- Mandibular nerve
- Lesser petrosal nerve
4) Foramen spinosum
- Middle meningeal artery
5) Carotid canal
- Internal carotid artery and nerve plexus
6) Jugular foramen
- Internal jugular vein
- Inferior petrosal sinus
- glossopharyngeal nerve (IX)
- vagus nerve (X)
- accessory nerve (XI)
7) Foramen Magnum
- Continuation of brain and spinal cord
- Vertebral arteries and nerve plexus
- Anteiror spinal artery
- Posterior spinal arteries
- Roots of accessory nerve (XII)
- Meninges
What foramina are we able to identify on a dry skull but not a wet one?
Foreamen lacerum
Name the sinuses in the skull
Being aware of air-filled spaces within the skull is essential. They are identifiable on radiographs.
Name the air-filled spaces and correspond them to the x-ray images.
1/4. Frontal sinuses
- Ethmoidal cells.
- Maxillary sinuses (only this sinus in neonates)
- Sphenoidal sinuses
Label
- Frontal sinuses
- Ethmoidal cells.
- Maxillary sinuses (only this sinus in neonates)
4) Frontal sinus - Sphenoidal sinuses
Name the intracranial foramina, and the structures passing through them
1) Foramen rotundum
- (middle cranial fossa)
- V2 maxillary division of the V trigeminal nerve
2) Foramen Ovale
* V2 Mandibular division of the V trigeminal nerve
3) Carotid canal
* Internal carotid artery
4) Foramen spinosum
* Middle meningeal artery
5) Jugular foramen
- Glossopharyngeal nerve,
- Vagus nerve
- Accessory nerve
- Internal jugular vein
6) Foramen magnum
- Spinal cord
- Vertebral arteries
7) Hypoglossal canal
* Hypoglossal nerve
8) Internal acoustic meatus
- Facial nerve
- Vestibulocochlear nerve
9) Foramen lacerum
* ____
10) Superior orbital fissure
- V1 Opthmalmic division of trigeminal nerve
- Occulomotor nerve
- Trochlear nerve
- Abducent nerve
- Superior opthalmic vein
11) Optic canal
- Optic nerve
- Ophthamic artery
12) Cribiform plate
* Olfactory nerves
What travels through
Foramen rotundum?
1) Foramen rotundum
(middle cranial fossa)
V2 maxillary division of the V trigeminal nerve
2) Foramen Ovale
V2 Mandibular division of the V trigeminal nerve
What travels through Carotid canal?
3) Carotid canal
Internal carotid artery
What travels through the Foramen Spinosum?
4) Foramen spinosum
Middle meningeal artery
What travels through the jugular foramen?
5) Jugular foramen
Glossopharyngeal nerve,
Vagus nerve
Accessory nerve
Internal jugular vein
What travels through the foramen magnum?
6) Foramen magnum
Spinal cord
Vertebral arteries
What travels through the hypoglossal canal?
7) Hypoglossal canal
Hypoglossal nerve
What travels through the Internal Acoustic Meatus?
8) Internal acoustic meatus
Facial nerve
Vestibulocochlear nerve
What travels through the Superior Orbital Fissure?
10) Superior orbital fissure
V1 Opthmalmic division of trigeminal nerve
Occulomotor nerve
Trochlear nerve
Abducent nerve
Superior opthalmic vein
What travels through the optic canal?
11) Optic canal
Optic nerve
Ophthamic artery
What travels through the Cribiform plates?
12) Cribiform plate
Olfactory nerves
