Osteo skull Flashcards
O
What are the two parts of the skull?
Neurocranium (brain box) - Viscerocranium (facial skeleton and mandible)
How many bones does the skull have?
28 bones in total
14 in neurocranium with three paired ear ossicles (MIS: Malleus, Incus, Stapes)
14 in the facial skeleton
What are the paired bones of the neurocranium
Parietal - Temporal - Malleus - Incus - Stapes
What are the unpaired bones of the neurocranium?
Frontal - Occipital - Sphenoid - Ethmoid
What are the paired bones of the facial skeleton?
Maxilla - Zygomatic - Nasal - Lacrimal - Palatine - Inferior nasal concha
What are the unpaired bones of the facial skeleton?
Mandible - Vomer
What is the location of the PTERION?
Located at the junction of the frontal, parietal, temporal, and sphenoid bones
What are the boundaries of the temporal region?
- Superior and posterior: superior temporal line
- Anterior: frontal and zygomatic bones
- Inferior: zygomatic arch
When does the anterior fontanelle close?
Closes between 12 to 18 months after birth
When does the posterior fontanelle close?
Closes 2 to 3 months after birth
When does the mastoid fontanelle close?
Closes between 6 to 18 months after birth
Where is the ASTERION located?
- Junction of the lambdoid, occipitomastoid, and parietomastoid sutures
Where is the GLABELLA located
Located between the eyebrows, on the frontal bone
What are the important parts of the auricle?
Helix - Antihelix - Tragus - Antitragus - Concha - Lobule
What is Reid’s base line?
- A horizontal line drawn from the infraorbital margin to the center of the external acoustic meatus (auricular point)
What is the Frankfurt’s horizontal plane?
- A line drawn from the infraorbital margin to the upper margin of the external acoustic meatus
What are the five views for studying the skull externally?
- Norma verticalis (superior) - Norma occipitalis (posterior) - Norma frontalis (anterior) - Norma lateralis (lateral) - Norma basalis
What is the clinical relevance of fontanelles in newborns?
- Helpful in age determination
- Indicators of intracranial pressure abnormalities (bulging or depressed fontanelles)
What is the parietal foramen
- Small foramen near the upper border of the parietal bone - Transmits emissary vein from scalp to superior sagittal sinus
What is the location of the coronal suture?
- Between the frontal and parietal bones
What is the location of the sagittal suture?
- Between the two parietal bones
What is the location of the lambdoid suture?
- Between the occipital and parietal bones
What is craniosynostosis?
- Premature ossification of skull sutures, leading to stunted brain growth and possible intellectual impairment
What happens if the anterior fontanelle is depressed?
- Indicates decreased intracranial pressure, commonly due to dehydration
