Skull Flashcards
What are the paired cranial bones?
Parietal and temporal
What are the unpaired cranial bones?
Frontal
Occipital
Sphenoid
ethmoid
What are the paired facial bones?
Zygomatic Lacrimal Nasal Palatine Maxillae Inferior nasal conchae
What are the unpaired facial bones?
Vomer
Mandible
Clinical significance of Pterion:
Pterion is where the frontal, parietal and sphenoid bones meet
Meningeal artery runs just deep to this landmark. Blunt trauma to this area can damage the meningeal artery = bleeding
What is the metopic suture?
Suture that divides both sides of the frontal bone in individuals with paired frontal bones
Significance of the frontal crest:
Attachment site for Faix Cerebri - protective connective tissue for the brain
Clinical note: Bone flaps
- Bone is not vascularized that deep so during surgery, you can keep the muscle overlying the bone to keep it vascularized
- Bone is wired or plated while healing. Heals best when flap incorporates the overlaying tissues (skin, muscle, fascia)
What are the sutures of the skull, and what do they connect?
Coronal (frontal and parietal)
Sagittal (both parietal bones)
Lamboid (parietal and occipital bones)
Squamous (temporal and parietal bones)
Significance of the foramen magnum?
Passageway for brainstem and numerous arteries and nerves
Significance of the superior nuchal line?
Attachment for muscles of the back and neck
Articulation of the occipital condyles
When nodding, occipital condyles articulate with the cervical vertebrae
Significance of the Sella Turcica:
Turkish saddle. Pituitary gland sits in this cranial depression on the sphenoid bone
Foramen Rotundum:
Exit point for maxillary branch of the trigeminal nerve (v2)
Foramen spinosum:
Exit point for middle meningeal artery
Significance of the superior orbital fissure:
Important exit point for nerves and structures going to the eye
Functions of the sphenoid bone:
Unites the cranial and facial bones
Articulates with almost every bone in the skull
Contains the sphenoid sinuses
Significance of these parts of the ethmoid bone: Crista Galli Orbital plate Perpendicular plate Ethmoidal labyrinth
- Attachment for falx cerebri
- forms medial wall of the orbit
- superior portion of the nasal septum
- contains the superior nasal and middle nasal conchae
What are the nasal conchae?
Bony elements that form the ethmoidal labyrinth. Superior and middle are part of the ethmoid bone while inferior is a separate bone
Significance of the cribiform plate:
Olfactory nerve exits here along lateral borders of the cribiform plate
Significance of the cribiform foramina (holes in the cribiform plate):
Passageway for olfactory nerve branches
Functions of the facial bones:
Provide shape, contour and individuality to the face
Important structural component of the orbit and nasal cavities
Anchor site for teeth of the upper and lower jaw
What makes up the zygomatic arch?
Zygomatic process of the temporal bone and the temporal process of the zygomatic bone
Significance of the Lacrimal groove formed by the lacrimal bone?
Forms the passageway of the nasolacromal duct
Which pair of bones make up the bridge of the nose?
Both pairs of nasal bones
The ala of the vomer articulates with ?
The vertical of the vomer forms the ?
- ala: sphenoid bone
- vertical plate; inferior portion of the nasal septum
The orbital process of the palatine bone forms the ….
The perpendicular plate forms the ….
The horizontal plate forms the ….
- part of the medial floor of orbit
- lateral wall of the nasal cavity
- posterior portion of the hard palate
Cleft lip and cleft palate is caused by…
Failure of fusion of the palatine bones. Opening can be anterior (cleft lip) or posterior (cleft palate).
Causes problems when speaking or swallowing
Functions of… Palatine process Incisive foramen Alveolar process Maxillary sinus
- posterior portion of hard palate
- separates hard palate from anterior nasal spine
- hold teeth of the upper jaw
- largest paranasal sinus in the skull
Maxillary fractures:
Le Fort I
Le Fort II
Le Fort III
- floor of the maxilla. Maxilla is the only one fractured
- fracture through the zygomatic-maxillary suture and the medial wall of the orbit
- fracture through the zygomatic bone and more of the orbit
Mandible articulates with the () of the temporal bone
Mandibular fossa
What make up the medial wall of the orbit?
Frontal process of the maxilla
Lacrimal bone
Lateral mass of the ethmoid bone
What make up the lateral wall of the orbit?
Zygomatic process of the frontal bone
Greater wing of sphenoid bone
Orbital surface of the zygomatic bone
What make up the roof of the orbit?
Lesser wing of the sphenoid bone
Frontal bone
What make up the floor of the orbit?
Perpendicular plate of the palatine bone
Orbital surface of maxilla
Zygomatic bone
What other bones/features make up the orbit?
Optic foramen
Superior orbital fissure
Inferior orbital fissure
What are the four paranasal sinuses?
Frontal
Sphenoid
Ethmoid
Maxillary
