Osteology Of Skull Flashcards
What are the parts of the cranium called?
Neurocranium
Viscerocranium
What are sutures?
The fibrous joints between the bones of the cranium
What is the term for depressions?
Fossae
What is the name given to roundish holes?
Narrow slits?
Foramina
Fissures
What is the function of the Neurocranium?
Encases and protects brain
What make up the Neurocranium?
Calvaria/skull cap made of the cranial floor and cranial cavity
How do the vault bones of the Neurocranium form?
Start as membranes then ossify (intrramembranous ossification)
Floor/ base starts as cartilage (Endochondral ossification)
What part of the skull makes up the viscerocranium?
Facial skeleton and jaw
How do the viscerocranium bones form?
Begin as membranes or cartilage and ossify
What is the name of the embryological structure that gives rise to the head and neck?
Pharyngeal arches (1,2)
What are the bones of the Neurocranium that are visible(calvaria/skull)?
Frontal bone
Parietal bones
Temporal bone
Occipital bones
What is the bone that forms the forehead?
Frontal bone
What is it called when the left and right frontal bones dont fuse together at the midline?
Metopic suture
What is the name of the bone that is posterior to the frontal bone?
Parietal bone (left and right parietal bone)
What is the name of the main bone that forms the lateral aspect of the Neurocranium?
Temporal bone
What is the name of the part of the temporal bone that houses the delicate structures of the inner and middle ear?
Petrous part of temporal bone
What is the name of the bone visible on the lateral aspect of the Neurocranium that’s anterior to the temporal bone but posterior to the orbital cavity?
Greater wing of sphenoid bone
What is the main bone forming the posterior aspect of the skull?
Occipital bone
What part of the occipital bone articulates with the C1 vertebra?
Occipital condyles
Look at the end of the lecture and label the bones of the Neurocranium
Blue = frontal bone
Red = parietal bones
Pink = temporal bone
Green = greater wing of sphenoid
Yellow = occipital bone
What is the name of the suture on the top of the skull joining the frontal bone and the parietal bone?
Coronal suture
What is the name of the suture joining the 2 parietal bones?
Sagittal suture
What is the name of the suture joining the occipital bone and the 2 parietal bones?
Lambdoid suture
What is the name of the point where the coronal suture and Sagittal suture meet?
Bregma
What is the name of the point where the Sagittal suture and lambdoid suture meet?
Lambda
What is the name of the large areas of unossified membranous gaps between flat bones of the calvaria which are present in development?
Anterior fontanelle
Posterior fontanelle
Go to slide 10 to look at the sutures and points that the suture meet
What is the importance of the fontanelles in the infant?
Allows for the skull size to increase as the brain size increases
What is the name of the condition where the fontalleles and sutures fuse too early?
Craniosynostosis
How should the anterior fontanelle appear in a healthy baby?
Slightly convex
What is concave and what is convex?
Concave is a U shape (imagine a bombs gone off in the ground)
Convex is a n shape
What does a bulgining anterior fontanelle indicate?
What does a sunken anterior fontanelle indicate?
Bulging = high intercranial pressure
Sunken = dehydrate/low intercranial pressure
How are the bones of the calvaria specially structured to provide strength?
Trilaminar arrangement
Describe the trilaminar arrangement of the bones of the calvaria:
Inner table (compact bone)
Spongy bone (dipole)
Outer table (compact bone)