Axial Skeleton Flashcards
What bones are part of the cranium? What bones are part of the postcranium?
Cranium -all the bones in your head
Postcranium- all the bones below the head
What bones are included in the axial skeleton?
Bones of the skull (cranium & mandible)
thorax
vertebral column
What bones are included in your appendicular skeleton?
Any bone not in the axial
example:
Upper Limb
Lower LImb
The skull can be divided into parts. What parts?
Mandible &
Cranium
The postcranial can be divided into?
vertebrae (coccyx, sacrum)
ribs
sternum
Is the skull one bone?
Np, various.
How can the skull be divided?
Nuero-Cranium (because it contains the brain)
&
Viscero-Cranium ( portion of the cranium that contains the organs, visceral means organs)
What is the function of the nuero-cranium and viscero cranium?
Nuero-Cranium: protects the brain
Viscero- cranium- protects the soft tissues of the face
Nuerocranium Bones and locations
Frontal bone- Forehead and top part of the orbits (eyes)
Parietal Bone- Sides of the skull;
Sphenoid Bone- portion on the temples, and forms posterior part of the eye orbit
Temporal Bone- by the ear on the side (deep to the ear)
Ethmoid bone - between the eyes, and behind the nasal bone, forms part of the medial aspect of the eye orbit
occipital bone- back of the head
Which bones are part of the nuerocranium that you can see inferiorly?
sphenoid, occipital, temporal bone
Which part of the ethmoid is part of the nasal cavity
Perpendicular plate
what shape is the sphenoid?
butterfly shaped
Looking down at the skull (superior view) what part of the ethmoid can you see?
The cribriform plate, crista galli
Name the sutures of the skull? What does it separate?
Sagittal suture- the middle separates the two parietal bones
Lambdoidal suture- separates occipital bone from parietal bones
squamousal suture- separates temporal bone from parietal bones
coronal suture- separates frontal bone from parietal bones
Name 4 features of the occipital bone.
Hypoglossal canal- underneath the occipital condyle
Jugular foramen- (one of the jugular vein goes through here)
Foramen Magnum- (passage of the spinal cord)
Occipital condyles
What is the purpose of the occipital bone?
To connect the cranium to the vertebrae.
Temporal Bone Features
Internal acoustic meatus
External acoustic meatus
Mastoid process
Styloid process
Foramen lacerum- gap where 3 bones come together occipital bone, sphenoid bone, temporal bone
Carotid canal
Mandibular fossa- madible articulates here
What is the supra orbital foramen?
Hole above the orbit (above the eye)
What are the sphenoid bone features?
Sella turcica- depression in the middle where the pituitary gland is
Optic canal- (can be seen from the front)
Superior orbital fissue- long opening (can be seen from the front)
Foramen rotundum - round hole
Foramen Ovale- oval hole
Foramen Spinosum- small hole
What forms the nasal septum?
ethmoid & vomer
What are the bones of the viscerocranium?
palatine bone lacrimal bone- tear gland sits zygomatic bone nasal bone maxilla inferior nasal concha- (responsible for regulating the flow of air in the nasal cavity) vomer mandible
What are the features of the maxilla?
Inferior orbital fissue
Infra-orbital foramen
What are the bone features of the mandible?
Mandibular condyle- (articulates with manibular fossa on the the temporal bone)
Mental foramen- (on the outside of the mandible on the chin)
Alveolar Part- (holds tooth roots)
Mandibular foramen- (inside of the mandible)
What are the two divisions of the axial postcranium?
Thoracic cage (ribs and sternum- protects heart and lungs
Vertebral column- protects spinal cord, transfers weight onto the lower limb, & it’s an
muscle attachement site
How is the vertebrae column divided?
cervical vertebrae- (C1-C7) thoracic vertebrae- (T1-T12) lumbar vertebrae- L1-L5) Sacrum- (5 fused vertebrae) Coccyx
What are the vertebrae column curves?
Lordosis & kyphosis
What is the spinal curve for the cervical, thoracic, lumbar, and sacral vertebrae?
cervical-Lordosis
thoracic- kyphosis
lumbar-Lordosis
scaral-kyphosis
When do the spinal curves develop?
When an infant starts walking
In pregnant women what kinda of curvature do they have?
Hyperlordosis
What is hyperkyphosis?
If the kyphosis curvature is too extreme it is hyperkyphosis (hunchback)
What is scoliosis?
abnormal lateral curvature
What features are present in all vertebrae?
-Transverse process (one on the left, one on the right)
-Centra (centrum)
(one exception C1)
-Spinous Process
-Vertebral Foramen (spinal cord pass through here)
What is the atlas, what is the axis?
C1 is the atlas
C2 is the axis
Why do the vertebrae get larger as you go down?
weight distribution
What articulates with the occipital condyles??
The atlas (holds the world)
What is the shake yes joint?
occipital bone and atlas
What does the hyoid bone attach to?
hyoid indirectly attaches to the styloid process
What is the only bone in your body that doesn’t directly articulate with another bone (floats in your neck)? How does it connect?
Hyoid bone, connects via muscle
Does the axis have a body?
No
What is the dens?
The axis has a dens that sticks up into the atlas.
What is the shake no joint?
atlas and axis connection
What is the transverse ligament?
ligament that wraps around the dens to the atlas so you can move your head side to side aka when saying ‘No”
What unique features do the cervical vertebrae have?
Transverse foramen
What unique features do the thoracic vertebrae have?
Costal facets (costal means rib)
What happens in the thoracic vertebrae?
attachment for ribs `
Where do ribs attach?
On the centrum (body) and transverse process
What is unique about lumbar vertebrae?
They lack:
transverse foramen &
costal facet
What are inter-vertebral disc?
pad of cartilage that separate the joint that connects the centrums together.
Important for shock absorption
What are inter-vertebral foramina?
Only exist when at least two vertebrae are together. The space they create between them. Spinal nerves go out through here
What is the articular processes?
Articular processes is where vertebrae articulate.
Superior set- articualte with vertebrae above it
Inferior set- articulate to the vertebrae below it
What is the vertebrae canal?
when the vertebrae are on top of each other the individual vertebrae foramen form a canal. The spinal cord goes out through here.
What do all vertebrae contain?
-Transverse process (one on the left, one on the right)
-Centra (centrum)
(one exception C1)
-Spinous Process
-Vertebral Foramen (spinal cord pass through here)
What are the features of the sacral?
Sacral body
Ala
Sacral foramina
Sacral Hiatus- exposes the vertebral canal (lack of spinous process)
What is the thorax?
contains lungs and heart, surrounded by the rib cage for protection
What divides the thorax and abdomen?
the diaphragm
What is part of the thorax/thoracic cage?
Sternum: Xiphoid process, manubrium, body
Ribs
Thoracic vertebrae
How many ribs do you have?
12 left and 12 right (women and men have the same amount)
what is the function of the thoracic cage?
- Attachment sites for muscles of breathing
- protection
How do the ribs attach to the thoracic vertebrae?
Ribs attach on the right and left of the costal facets that are on the transverse process and centrum
Does the rib directly attach to the sternum?
No attaches via the costal cartilage
Why does the posterior rib attach bone to bone (via costal facet) versus the front ribs that attach the costal cartilage?
Because of breathing.
When you breathe your ribs expand laterally you need that flexibility.
Every rib is connected to the sternum. True/False
True
Name the three functional groups of the ribs.
Vertebrosternal Ribs
Vertebrochondral Ribs
Vertebral Ribs
How does the vertebrosternal attach?
Vertebrosternal Ribs- ribs attach from the vertebrae to the sternum via an individual costal cartilage (first 7 ribs)
How does the Vertebrochondral Ribs
ribs attach from the vertebrae to the sternum via a fused costal cartilage (8-10)
How do the Vertebral Ribs attach?
They don’t attach to anything on the front.
What part of the rib attaches to the costal facet on the centrum?
head
What part of the rib attaches to the costal facet on the transverse process?
the tubercle of the rib
