Skull Flashcards
What makes up the axial skeleton?
Skull
Vertebral Column
Thoracic Cage
What makes up the appendicular skeleton?
Upper Limbs
Lower Limbs
Pectoral Girdle
Pelvic Girdle
What are the 8 cranial bones, paired and unpaired?
Paired –
- Temporal
- Parietal
Unpaired –
- Frontal
- Occipital
- Sphenoid
- Ethmoid
What are the 14 facial bones, paired and unpaired?
Paired –
- Zygomatic
- Lacrimal
- Nasal
- Palatine
- Maxillae
- Inferior Nasal Conchae
Unpaired –
- Vomer
- Mandible
What suture runs across the top of the frontal bone, separating it from the parietal bone?
Coronal Suture
In some individuals, the frontal bone can be considered “paired” and be brought together by what suture?
Metopic Suture
This is the attachment site for the Falx Cerebri, which is a protective CT for the brain.
Frontal Crest
What suture divides the parietal bone into left and right sides?
Sagittal Suture
What suture separates the parietal bone from the occipital bone?
Lambdoid Suture
What suture separates the parietal bone from the temporal bone?
Squamous Suture
There are two lines on the parietal bone that are attachment points for muscles of mastication. They are called…
Superior Temporal Line
Inferior Temporal Line
This is a large opening that is eventually closed off during mastication so the eyeballs do not bounce around.
Fenestra
This is a terminal branch of V1 (Ophthalmic) that runs through the Supraorbital Foramen on the frontal bone.
Supraorbital N.
This is a component of the frontal bone that can be palpated between the eyes.
Glabella
This structure separates the 2 hemispheres.
Frontal Crest
When performing surgery in the cranial cavity, the periosteum has poor osteogenic properties and vasculature. To combat this, the bone is usually reflected with what?
With overlaying tissues attached to it (i.e., skin, muscle, fascia)
***Heals the best when this is done!
This bone houses the middle and inner ear.
Temporal bone
This component of the temporal bone is for sound to come in and hit the tympanic membrane.
External Acoustic Meatus
This component of the temporal bone is for nerves to pass through.
Internal Acoustic Meatus
***CN VII (Facial) and VIII (Vestibulocochlear)
This is located on the interior of the temporal bone and is for dural venous sinus drainage.
Groove for the Sigmoid Sinus
This component of the occipital bone is generally larger in males than females.
External Occipital Protuberance
This component of the occipital bone is a large passageway for the brainstem and numerous arteries and nerves.
Foramen Magnum
These components of the occipital bone provide attachment for muscles of the back and neck.
Superior Nuchal Line
Inferior Nuchal Line
When a person nods to say “YES”, what is articulating?
Occipital condyles with the cervical vertebrae
Internally, the occipital bone has a path for venous drainage for the brain. What are the grooves that involve the drainage?
Groove for Sigmoid Sinus (also part of temporal bone)
Groove for Transverse Sinus
Groove for Superior Sagittal Sinus
What does the superior sphenoid bone look like?
BATMAN
On the superior sphenoid bone, this is a cranial depression where the Pituitary Gland sits.
Sella Turcica (“Turkish Saddle”)
On the superior sphenoid bone, this is the exit point for the Maxillary Branch of Trigeminal N. (V2).
Foramen Rotundum
On the superior sphenoid bone, this is the exit point for the Mandibular Branch of Trigeminal N. (V3).
Foramen Ovale
On the superior sphenoid bone, this is the exit point for the Middle Meningeal A.
Foramen Spinosum
This is the thinnest point of the skull, because it is a meeting point of multiple sutures.
Pterion
Why is it bad if you’re struck in the head at the Pterion?
Because it is the thinnest point of the skull and the Middle Meningeal A. runs deep to it. If you’re hit in the head there, you are very likely to bleed from the artery.
What does the anterior/inferior view of the sphenoid bone look like?
BUTTERFLY
This bone unites the cranial and facial bones, and articulates with almost every bone in the skull.
Sphenoid
This component of the ethmoid bone is the attachment point for the Falx Cerebri.
Crista Galli
This part of the ethmoid bone forms the medial wall of the orbit.
Orbital Plate
This part of the ethmoid bone is the superior portion of the nasal septum.
Perpendicular Plate
The Ethmoidal Labyrinth or Lateral Mass consists of what?
Superior Nasal Conchae
Middle Nasal Conchae
Orbital Plate
This conchae is considered its own bone.
Inferior Nasal Conchae
The superior ethmoid bone has what components?
Ethmoidal Air Sinuses
Cribriform Plate
Cribriform Foramina
What cranial nerve descends along the lateral borders of the Cribriform Plate (Ethmoid bone) and uses the Cribriform Foramina as passageway for its branches.
Olfactory N. (CN I)
What are the different cranial fossae?
Anterior Cranial Fossa
Middle Cranial Fossa
Posterior Cranial Fossa
This bone has an Orbital Surface that forms the lateral wall of the orbit.
Zygomatic
What does the Zygomatic Arch consist of?
Zygomatic Process of Temporal Bone
Temporal Process of Zygomatic Bone
This bone is part of the medial wall of each orbit.
Lacrimal
This is the passageway for the Nasolacrimal Duct.
Lacrimal Groove
This bone resembles a farming plow and is triangular shaped.
Vomer
This component of the Vomer articulates with the Sphenoid.
Ala
This component of the Vomer forms the interior portion of the Nasal septum.
Vertical Plate
This component of the Palatine bone is part of the medial floor of the orbit.
Orbital Process
This component of the Palatine bone is part of the lateral wall of the nasal cavity.
Perpendicular Plate
This component of the Palatine bone is part of the posterior portion of the hard palate.
Horizontal Plate
What can occur if the palatine processes do not develop properly?
Cleft Lip
Cleft Palate
This component of the Maxilla is part of the posterior portion of the hard palate.
Palatine Process
***Failure to develop can result in cleft palate
This component of the Maxilla separates the hard palate from the anterior nasal spine.
Incisive Foramen
This component of the Maxilla holds the teeth of the upper jaw.
Alveolar Processes
This is the largest paranasal sinus in the skull.
Maxillary Sinus
***Within Maxilla bone
This type of Maxillary fracture is horizontal.
Le Fort I
***Speak No Evil – only involves mouth
This type of Maxillary fracture is pyramidal.
Le Fort II
***See No Evil – goes to eye orbit
This type of Maxillary fracture is complete craniofacial separation.
Le Fort III
***Hear No Evil – most of face, goes to ear
The Condylar Process of the Mandible and the Mandibular Fossa of the Temporal bone make up what joint?
Temperomandibular Joint (TMJ)
What are the 7 bones that make up the orbital complex?
Frontal Sphenoid Zygomatic Maxilla Lacrimal Ethmoid Palatine
What makes up the roof of the orbit?
Lesser wing of Sphenoid
Frontal bone
What makes up the lateral wall of the orbit?
Zygomatic Process of Frontal bone
Greater Wing of Sphenoid
Orbital Surface of Zygomatic bone
What makes up the medial wall of the orbit?
Frontal Process of Maxilla
Lacrimal bone
Lateral Mass of Ethmoid bone
What makes up the floor of the orbit?
Perpendicular Plate of Palatine bone
Orbital Surface of Maxilla
Zygomatic bone
What are the Paranasal Sinuses?
Frontal
Sphenoid
Ethmoid
Maxillary
What are the 4 different fontanelles in the fetal skull?
Anterior Fontanelle
Sphenoid Fontanelle
Mastoid Fontanelle
Posterior Fontanelle
This fontanelle is at the meeting of the frontal bone and parietal bones.
Anterior Fontanelle
This fontanelle is at the meeting of the parietal bones and the occipital bone.
Posterior Fontanelle
This fontanelle is at the meeting of the frontal bone, parietal bone, temporal bone, and sphenoid bone.
Sphenoid Fontanelle
This fontanelle is at the meeting of the occipital bone, parietal bone, and temporal bone.
Mastoid Fontanelle
List the cranial nerves and their foramina in order.
CN I -- Cribriform Plate CN II -- Optic Canal CN III, IV, V(V1), VI -- Superior Orbital Fissure CN V(V2) -- Foramen Rotundum CN V(V3) -- Foramen Ovale CN VII, VIII -- Internal Acoustic Meatus CN IX, X, XI -- Jugular Foramen CN XII -- Hypoglossal Canal
***On the skull, the foramina go in order from anterior to posterior!
This foramina lies below the Foramen Ovale and is the exit site for the Middle Meningeal A.
Foramen Spinosum
This is the foramina where the Branchial Motor component of the Facial N. (CN VII) exits out onto the face.
Stylomastoid Foramen