Skull Flashcards
How many bones are in the skull?
22
What is the primary function of the neurocranium?
Encases and protects the brain
How many bones make up the neurocranium?
8 bones
What are the flat bones of the skull called?
Calvaria or calvarium
What structure is found in the cranial cavity?
Brain
How many bones make up the viscerocranium?
14 bones
The viscerocranium is associated with which part of the skeleton?
Facial skeleton and jaw
What are the four bones that make up the anterior part of the calvarium?
Frontal bone x 1, Parietal bones x 2, Sphenoid bone x 1
The calvarium is the upper part of the skull that encloses the brain.
How many temporal bones are found in the lateral view of the skull?
Temporal bones x 2
Temporal bones are located on the sides of the skull and are involved in the structure of the skull.
What is the total number of occipital bones in the human skull?
Occipital bone x 1
The occipital bone is located at the back of the skull and forms the base of the cranium.
True or False: The bones of the calvarium are flat.
False
The bones of the calvarium are not flat; they have complex shapes contributing to the structure of the skull.
Fill in the blank: The _______ bone is found under the calvarium.
[Sphenoid bone]
The sphenoid bone is a complex bone located at the base of the skull, contributing to the cranial structure.
What are the functions of the skull?
• Structure
• Site of muscular attachment
• Mastication
• Facial expression/communication
What is the role of the skull in mastication?
It provides a site for muscular attachment.
Which muscle is associated with facial expression?
Frontalis
What structure provides attachment for cartilaginous structures like ears and nose?
Skull
What does the skull form scaffolding for?
Nasal and oral cavity
The skull is a site of attachment for which structures?
• Muscles
• Cartilaginous structures
• Teeth
Fill in the blank: The _______ is a site of muscular attachment for facial expression.
Frontalis
True or False: The skull is a site of attachment for teeth.
True
What are the names of some muscles associated with the skull?
• Auricularis
• Occipitalis
• Parotideo-masseteric
Fill in the blank: The _______ is associated with the parotid gland and masseter muscle.
Parotideo-masseteric
What is the Galea aponeurotica?
A structure associated with the skull that provides muscular attachment.
What is the calvarium?
The upper part of the skull that encloses the brain
The calvarium is also known as the skull cap.
What are sutures in the context of the skull?
Fibrous joints that connect the bones of the skull
Sutures allow for growth of the skull and provide stability.
What is the coronal suture?
A suture that separates the frontal bone from the parietal bones
The coronal suture runs from side to side across the skull.
What is the bregma?
The point where the coronal and sagittal sutures meet
The bregma is an important landmark in cranial anatomy.
What is the sagittal suture?
A suture that runs along the midline of the skull, separating the left and right parietal bones
The sagittal suture extends from the front to the back of the skull.
What is the lambda?
The point where the sagittal and lambdoid sutures meet
The lambda is located at the posterior part of the skull.
What is the lambdoid suture?
A suture that separates the occipital bone from the parietal bones
The lambdoid suture is shaped like an inverted ‘V’.
What view of the skull is referred to as the superior view?
The view from above the skull
This view allows for the examination of the calvarium and sutures.
What view of the skull is referred to as the posterior view?
The view from behind the skull
This view is important for analyzing the occipital region.
What is the purpose of sutures in the newborn skull?
Allows for movement during delivery and growth as the child develops
Sutures are not fused in the newborn, providing flexibility during birth and accommodating brain growth.
At what age does the metopic suture typically close?
3-9 months
The metopic suture divides the frontal bone in the child.
What type of joint are sutures classified as?
Fibrous joint
Sutures are very strong with limited mobility.
Name the four main sutures found in the typical newborn skull.
- Metopic suture
- Coronal suture
- Sagittal suture
- Lambdoid suture
These sutures contribute to the structure and flexibility of the skull.
True or False: Sutures in the newborn skull are completely fused.
False
Sutures are not fused, allowing for movement and growth.
What is the purpose of sutures in the newborn skull?
Allows for movement during delivery and growth as the child develops
Sutures are not fused in the newborn, providing flexibility during birth and accommodating brain growth.
At what age does the metopic suture typically close?
3-9 months
The metopic suture divides the frontal bone in the child.
What type of joint are sutures classified as?
Fibrous joint
Sutures are very strong with limited mobility.
Name the four main sutures found in the typical newborn skull.
- Metopic suture
- Coronal suture
- Sagittal suture
- Lambdoid suture
These sutures contribute to the structure and flexibility of the skull.
True or False: Sutures in the newborn skull are completely fused.
False
Sutures are not fused, allowing for movement and growth.
What are fontanelles?
The ‘gaps’ between the bones of an infant’s skull
Commonly known as ‘soft spot’
When does the posterior fontanelle typically close?
2-3 months after birth
Location of the posterior fontanelle is at the lambda
When does the anterior fontanelle typically close?
18 months after birth
Location of the anterior fontanelle is at the bregma
Why are fontanelles important during a neonate examination?
They are part of the examination if the neonate is unwell
What does a sunken fontanelle indicate?
Dehydration
What does a bulging fontanelle indicate?
Increased intracranial pressure
What is craniosynostosis?
Inappropriate closure of sutures
It involves the fusion of skull sutures too early, altering the shape of the skull.
What can craniosynostosis lead to?
Increased intracranial pressure and ultimately brain damage
What is the result of early fusion of sutures?
Altered shape of the skull
What is scaphocephaly?
A type of craniosynostosis characterized by an elongated skull
What is trigonocephaly?
A type of craniosynostosis characterized by a triangular-shaped forehead
What is plagiocephaly?
A type of craniosynostosis characterized by an asymmetrical skull shape
What is brachycephaly?
A type of craniosynostosis characterized by a broad, short skull
Fill in the blank: Craniosynostosis involves the inappropriate closure of _______.
sutures
True or False: You need to know about the different types of craniosynostosis.
False
What is the thinnest part of the skull
The pterion
How many bones form the pterion
4 (temporal, parietal, frontal and sphenoid)
What 4 bones form the pterion
Temporal, parietal, frontal and sphenoid
What artery sits just behind the pterion
The middle mengingeal artery
What can damage to the pterion lead to
Intracranial haemorrhage
What is Paget’s disease
Disease affecting bone formation. Leads to weaker more ‘bulky’ bones
What main bones does Paget’s disease affect
Skull, lumbosacral spine and pelvis
What does Paget’s disease in the skull cause
Pain, deformities/ changes to shape of skull, compression of structures- eg. Nerves responsible for hearing
What is the cranial floor of the skull
Where the brain sits
What are the holes in the cranial floor called
Foramen/ foramina
Why are there foramen in the cranial floor
Allow passage of nerves and vasculature
What is the bone at anterior of the cranial floor called
Frontal
What bone sits in the middle of the frontal bone on the cranial floor of the skull
Ethmoid bone
What is the bone in the middle of the cranial floor (looks like a butterfly)
Sphenoid bone
What bones sit posterially/ laterally to the sphenoid bone on the cranial floor
Temporal bones (one either side)
What are the lateral bones of the cranial floor
Parietal
What is the bone at the posterior of the cranial floor
Occipital bone
What is the viscerocranium
Part of the skull that forms face and jaw
How many bones make up the viscerocranium
14
What are the 14 bones that make up the viscerocranium
2x zygomatic
2x maxilla
2x nasal
2x lacrimal
2x palatine
2x inferior nasal concha
Mandible
Vomer
What bone do the upper teeth insert into
Maxilla
What bone do the lower teeth insert into
Mandible
What bone does the mandible articulate with and at what joint
Temporal- at temporomandibular joint (TMJ)
What is the function of the vomer bone
Helps divide the nasal cavity into left and right sides
Where is the inferior nasal concha
At the lateral walls of the nasal cavity- bony bump
What is the function of the inferior nasal concha
Helps slow airflow into the nose and help warm and moisten air
What do the two palatine bones form
The palate
What is the function of the palatine bones
Help divide the nasal and oral cavities
What bones make up the eye socket
Frontal, sphenoid, lacrimal, ethmoid, maxilla and zygomatic
What are bones make up the roof of the nasal cavity
Frontal, ethmoid, sphenoid, nasal
What bones make up the floor of the nasal cavity
Palatine and maxilla
What bones make up the lateral walls of the nasal cavity
Ethmoid and inferior nasal conchae
What bones make up the septum/ medial wall of the nasal cavity
Ethmoid and vomer + cartilage
