axial skeleton

cranium, facial bones, vertebral column

what is the skeleton for?

* locomotion
* shape, support, and protection
* calcium (and other minerals) reservoir
* blood cells formation

what is the skull made up of?

22 bones

* 8 cranial bones
* 14 facial bones

cranial bones

* frontal
* occipital
* sphenoid
* ethmoid
* parietal x2
* temporal x2

facial bones

* nasal x2
* zygomatic x2
* maxillary x2
* mandible
* lacrimal x2
* inferior conchae x2
* palatine bone x2
* vomer bone

areas of cranial fossae

* superior (anterior)
* middle
* inferior (superior)

what is an orbit?

the eye socket bones

how many bones are in an orbit?

7

bones within an orbit

* sphenoid bone
* zygomatic bone
* frontal bone
* ethmoid bone
* lacrimal bone
* maxilla
* palatine bone

how many paranasal sinuses are there

4 in total

* frontal, sphenoid, ethmoid, maxillary sinus

location of frontal and sphenoid paranasal sinuses

in a sagittal section with the nasal septum removed

location of ethmoid paranasal sinus

the superior and middle nasal conchae

(not the inferior, this is a separate bone)

what is the nasal conchae comprised of

* superior
* middle
* inferior

foramina

a passage where things run through

* bigger than a fissure

name the 7 foramina and what bones they attach to

* foramen magnum (occipital)
* jugular foramen (occipital temporal)
* nasolacrimal (maxillary/lacrimal)
* internal acoustic foramen (temporal)
* foramen ovale (sphenoid)
* incisive foramen (maxilla)
* olfactory foramina (ethmoid)

parts of the temporal bone

* zygomatic process
* mastoid process
* styloid process
* mandibular fossa (cutout of mastoid process)

what is a zygomatic process?

a zygomatic process of temporal bone

what is a zygomatic arch?

* temporal process of zygomatic bone
* zygomatic process of temporal bone

5 things the ethmoid bone consists of?

* cribriform plate
* crista galli (cocks comb)
* perpendicular plate
* superior nasal concha
* middle nasal concha

whats special about the inferior nasal concha

* doesnt belong to ethmoid bone or any bone
* same function at the other nasal conchae
* create turbulent airflow

what shape is the sphenoid bone? where is it?

* shape of a bat
* spans the base of the cranium side to side

features of the sphenoid

* sella turcica
* greater wing
* lesser wing
* anterior clinoid process
* posterior clinoid process

what is the sella turcica for

housing and giving space to pituitary gland

what does the anterior clinoid process come off of?

lesser wing

sagittal suture

between each parietal bone

coronal suture

between parietal and frontal bones

lamboid suture

between occipital and parietal bones

squamous suture

between parietal and temporal bones

name 6 features of the mandible

* ramus (ascending)
* angle
* body (horizontal)
* submandibular fossa
* coronoid process
* condylar process

what is the angle of the mandible?

where the ramus and body meet

what does the condyloid process articulate with?

mandibular fossa of temporal bone at TMJ

* temporomandibular joint

coronoid is the site of attachment for what?

temporalis muscle

where is the palatine? what shape?

* L shape
* horizontal plate is back of mouth (top)
* vertical goes up into orbit

what area is the zygomatic bone?

cheekbone and lateral rim of orbit

smallest bone in the skull?

lacrimal bone

what is a lacrimal groove?

a shallow depression that leads to nasolacrimal canal

what is a nasolacrimal canal?

narrow passageway

* encloses tear duct
* most medial

what forms the nasolacrimal canal

lacrimal bone and maxilla

what are the associated bones of the skull?

* hyoid bone
* auditory ossicles

what shape is the jugular foramen?

a heart

what bones does the hyoid bone articulate with

* it doesnt
* suspended via ligaments and muscles

where is the hyoid one suspended from?

from the styloid process

where is the hyoid bone located?

anterior part of neck between mandible and larynx

what attachment points does the hyoid provide?

* muscle of neck
* tongue
* pharynx

how many vertebrae are there?

33

how many cervical vertebrae

7

how many thoracic vertebrae

12

how many lumbar vertebrae

5

how many sacral vertebrae?

5 fused bones

how many coccygeal/coccyx vertebrae?

3-5 fused bones

what parts of the vertebrae are not movable?

sacral and coccyx

what makes up a vertebra?

* body
* lamina
* pedicle
* processes
* vertebral foramina

what processes are in a vertebra?

* spinous process
* transverse process

what is a vertebral foramen?

houses spinal cord

* hole in each vertebrae

what do all cervical vertebrae have? what is unique about them?

transverse foramina

* 2 holes medial to the transverse processes
* bifid tip of spinous process

what are the atypical cervical vertebrae?

* C1
* C2
* C7

features of C1/atlas

* missing body
* missing spinous process

features of C2/axis

* missing body
* has dens and bifid spine

features of C7

* prominent non bifid spinous process
* most degree of movement

what allows the ‘yes’ motion of the head?

the articulation between the skull/occipital condyles and the atlas (C1)

what allows the ‘no’ motion of the head?

the atlas on the axis

is there an intervertebral disc in between C1 and C2?

no

what is a dens?

* its part of C2
* a fusion between C1 and C2

what forms the pivot for rotation between C1 and C2?

transverse ligament

unique feature of thoracic vertabrae

have articular facets (demifacets) for the articulation of the ribs

what are the 3 articular facets of the thoracic vertebrae?

* superior articular facet
* transverse costal facet
* inferior costal facet

what is the shape of thoracic vertebrae?

heart shaped

what does costal mean?

ribs

where do ribs attach

thoracic vertebrae

what is a demifacet? what attaches there?

* half of a facet (transverse and inferior)
* part of the head of the rib

what facets do the ribs attach to?

* inferior costal facet
* transverse costal facet

unique features of lumbar vertebrae

* largest
* have no demifacets for rib attachment
* vertebral foramen is triangle shaped

what shape is the vertebral foramen in lumbar vertabrae?

triangle shaped

how many PAIRS of ribs are there?

12

what ribs articulate with the sternum directly with their cartilage?

1-7

what ribs are ‘false ribs’?

8-10

what ribs are ‘floating ribs’

11 and 12

how do ribs attach to the sternum?

costal cartilage

what composes a singular rib?

* head with 2 articular facets
* neck
* tubercle
* angle
* costal groove
* facet for costal cartilage

what does the head of the rib articulate with?

the vertebrae

whats a tubercle

small projection that attaches to something

what ribs dont have tubercular facets?

11 and 12

name the 3 parts of a sternum

* manubrium
* body
* xiphoid process

why is the sternum important in CPR

* used to assess consciousness
* they rub it because its uncomfortable

what does the manubrium articulate with?

* clavicle
* costal cartilage of the first rib

where is the jugular notch located

between the 2 clavicular notches (middle)

what does the body of the sternum articulate with superiorly?

the manubrium

* via the sternal angle

what is the sternal angle?

site of attachment of 2nd rib

what does the body of the sternum articulate with inferiorly?

xiphoid process

whats commonly snapped off during CPR?

xiphoid process