Lecture 4c Flashcards
Axial Skeleton
- supports and protects the organs
- 80 bones
- provide attachment sites for many muscles
The skull
contains the cranial and the facial bones
- cranial bones have 8 bones and have direct contact with the brain
- facial bones have 14 bones and don’t have contact with the brain
Cranial bones
parietal bone temporal bone occipital bone frontal bone sphenoid bone ethmoid bone
What cranial bones are flat bones ad which are paired?
parietal -paired
temporal -paired
occipital
frontal
What cranial bones are irregular bone
sphenoid
ethmoid
Sutures
immovable, interlocking joints
- coronal
- sagittal
- lambdoid
- squamous
Coronal suture
between the frontal and the parietal bones
Squamous suture
between the parietal and temporal bones
Lambdoid suture
between the parietal and occipital bones
Sagittal suture
between the parietal bones
Supraorbital foramen
passage of supraorbital nerve and vessels (anterior view of frontal bone)
-forms the superior portion of orbits
The anterior view of the frontal bone you can see the coronal suture between frontal and parietal bone
Occipital condyle
articulates with the vertebrae (where the head of the cranium sits on the vertebral column
-found in the posterior and inferior view of the occipital bone
Foramen magnum
passage of the spinal cord
-found in the posterior and inferior view of the occipital bone
Zygomatic process
joins the zygomatic bone
-lateral view of the temporal bone
Mastoid process
neck muscles attach and can be palpated
(you can feel the large lump behind your ear)
-lateral view of the temporal bone
Styloid process
attachment for muscles of tongue and larynx
-lateral view of the temporal bone
External acoustic meatus
opening of the auditory (ear) canal
-lateral view of the temporal bone
Mandibular fossa
articulates with mandible (jaw)
-lateral view of the temporal bone
Sphenoid bone
irregular bone that articulates with all cranial bones (ties all the cranial bones together)
-forms the sphenoidal sinuses
Sella Turcica (Hypophyseal fossa)
houses the pituitary glands (chamber)
-sphenoid bone superior view
Ethmoid bone
articulates with half of bone in the skull
-contains the crista galli, perpendicular plate and ethmoidal sinuses /air cells
Crista galli
helps support and attach the brain
Perpendicular plate
forms inner/intermediate architecture of the nose (septum)
Ethmoidal sinuses/air cells
open into the nasal cavity, paired sinuses
What does the bones of the face do?
- shape of the face
- forms part of orbitals and nasal cavities
- supports the teeth
- muscle attachment
What are the bones of the face
zygomatic bone nasal bone lacrimal bone maxilla palatine bone inferior nasal conchae
vomer
mandible
What bones of the face are paired
zygomatic bone nasal bone lacrimal bone maxilla palatine bone inferior nasal conchae
What bones of the face are unpaired
vomer
mandible (jaw)
Mandible
-lower jaw
-unpaired and comprised of the body and the ramus
contains:
condylar process
coronoid process
alveolar process
condylar process
mandibular fossa (of temporal bone), forms TMJ
Coronoid process
temporalis muscles attachment =allows jaw to open and close
Alveolar process
contains sockets for teeth (houses the lower teeth)
Maxilla
2 paired bones that are fused together-comprised of the upper jaw
contains:
alveolar process
palatine process
Alveolar process (maxilla)
houses the upper teeth
Palatine process
most of the hard palate (anterior)
Maxilla sinus
paired, large cavity from orbits to alveolar processes
Zygomatic bone
-cheekbone
-paired and forms part of orbits
contains:
maxillary process
frontal process
temporal process
Maxillary process
articulates with the maxilla
-part of the zygomatic bone
Frontal process
articulates with the frontal bone
-part of the zygomatic bone
Temporal process
articulates with the zygomatic process of temporal bone
-part of zygomatic bone
Vomer bone
- unpaired
- triangular shape
- helps form inferior nasal septum
Palatine bone
-paired and is an “L” shaped bone
contains:
horizontal plate
vertical (perpendicular) plate
Horizontal plate
from posterior hard palate
Vertical (perpendicular) plate of Palatine bone
forms nasal cavity
posterior and lateral of nasal cavity
Lacrimal bone
- paired and anterior
- forms medial walls of orbits
- groove (lacrimal fossa) > tear drainage into nasal cavity
Nasal bone
- paired, anterior
- bones and hyaline cartilage
- forms part of the nasal cavity
Inferior nasal conchae
-paired
-form part of lateral nasal cavity wall
-air passes through conchae with high surface area
- allows for heating, humidification and filtering of inhaled air
increases the amount of air to pass through body
What are the four paired sinuses
maxillary (largest)
sphenoid
ethmoid
frontal
The paranasal sinuses are air-filled spaces in the skull around the nasal cavity for:
- mucous production
- lightens skull
- resonant chambers for sound production while speaking
Hyoid bone
- located between the mandible and larynx
- does not articulate with another bone
- ligament connects it with the styloid process of temporal bone
List the vertebral column, how many bones are in each section and where they are located
cervical- 7 bones (form neck)
thoracic- 12 bones (form the superior portion of the back)
lumbar - 5 bones (inferior region of back)
sacrum- 5 fused vertebrae
coccyx - 4 fused vertebrae
What forms the vertebral foramen
the vertebral arch and the vertebral body (passage of the spinal cord)
Spinous process
projects posteriorly
Transverse process
-lateral projection
Articular processes and facet
-articulates with other vertebrae (superior and inferior)
Atlas C1
-deep superior articular facets
-articulates with the occipital condyles of the occipital bone
-does not have a body or spinous process
nod yes
Axis C2 “dens”
dens=superior projection
the missing body of atlas- cradles the anterior arch of atlas
nod no
atlantoaxial joint
Dens C2 allows for the rotation of the skull due to the transverse ligaments
Sacrum
-5 vertebrae
-fuse between 20-30years
Alas: “wings” on each side that articulates with the os coxae along the auricular surface
Sacral promontory: the anteriorsuperior edge of the first vertebrae (near the body’s centre of gravity)
Coccyx
- fusion of 4 vertebrae
- common: tail bone
- attachment site for ligaments and muscles
Thoracic Cage
- bony frame around the chest composed of the:
1. thoracic vertebrae
2. sternum
3. ribs
4. costal cartilage - protects the lungs, heart, trachea, esophagus and other thoracic organs
Sternum
- common: breastbone
- anterior midline
- contains 3 components:
1. marubrium
2. body
3. xiphoid process
The ribs
12 pairs (flat bone) articulates posteriorly with the thoracic vertebrae
True ribs
ribs 1-7
articulates anteriorly with the sternum via costa cartilage
vertebrosternal ribs
False ribs
ribs 8-12
their costal cartilage does not attach with the sternum
vertebrochondral ribs
Floating ribs
false ribs (paired 11-12) does not attach to the sternum
Rib anatomy and articulation with the thoracic vertebrae
Angle: curving towards the sternum
- articular facet of the head for the thoracic vertebrae
- articular facet of the tubercle for the transverse process