Part 1:
The Axial Skeleton:
Axial Skeleton = skull + thoracic cage + vertebral column
Axial Skeleton
The Skull
Skull = cranial bones + facial bones
Cranial Bones:
Parietal (2)
Occipital (1)
Sphenoid (1)
Temporal (2)
Frontal (1)
Ethmoid (1)
Facial Bones:
Mandible (1)
Maxillae (2)
Lacrimal (2)
Nasal (2)
Zygomatic (2)
Vomer (1)
Palatine (2)
Skull Sutures (joints):
Identify the bones each suture joins
squamous suture
coronal suture
sagittal suture
lambdoidal suture
Frontal Bone:
supraorbital foramen (or notch)
supraorbital margin
Temporal bones:
mandibular fossa
zygomatic process
mastoid process
styloid process
carotid canal
jugular foramen
foramen lacernum
external acoustic meatus
internal acoustic meatus
Occipital Bone:
occipital condyles
foramen magnum
hypoglossal canal
occipital protuberance
Sphenoid Bone:
greater wings
lesser wings
superior & inferior orbital fissures
sella turcica
optic canal
foramen ovale
foramen spinosum
foramen rotundum
Ethmoid:
cribriform plate
forms roof of nasal cavity
cribform foramina
crista galli
perpendicular plate
nasal conchae
Mandible:
body & ramus of mandible condylar process
coronoid process
mental foramen
mandibular foramen
alveolar process
mandibular symphysis
Maxillae:
alveolar process
palatine processes
infraorbital foramen
incisive fossa
Lacrimal Bone:
lacrimal fossa
Paranasal Sinuses = air-filled space w/in skull bones:
Frontal Ethmoid Sphenoid Maxillary
Hyoid Bone:
does not articulate with any other bone.
serves as attachment site for muscles of tongue and neck
The Skeletal System
Axial Skeleton: vertebrae, sternum, ribs
Vertebral Column = 3 groups of vertebrae + sacrum + coccyx
How many vertebrae are in each grouping?
Cervical = 7 Thoracic = 12 Lumbar = 5
Vertebral Curvatures:
“Primary” vertebral curvatures
develop before birth
“Secondary” vertebral curvatures
develop in the 1st year of life
General Features of Vertebrae:
body
transverse process
spinous process
vertebral foramen
intervertebral foramina
superior & inferior articular facets
pedicle & lamina
vertebral arch
Cervical Vertbrae (C1- C7)
C1 = “atlas” C2 = “axis” C7 = “vertebra prominens”
odontoid process ( dens) on C2 vertebra
transverse foramen
Thoracic Vertebrae (T1-T12)
costal facet (head of rib fits here)
transverse costal facet
(tubercle of rib fits here)
spinous processes
(longer, downward shape compared to
cervical & lumbar vertebrae)
Lumbar Vertebrae (L1-L5)
“chunkier” than cervical or thoracic vertebrae
Sacral Vertebrae / Sacrum
fusion of five sacral vertebrae (S1-S5)
articulates with L5 and coccyx
sacral canal
sacral hiatus
sacral foramina
sacral promontory
anterior surface of S1
median sacral crest
and your tailbone...
Coccyx/ coccygeal vertebrae
Thoracic Cage =
Sternum + Ribs + Costal cartilage + Thoracic Vertebrae
Sternum
manubrium
body
xiphoid process
jugular notch
Ribs/Costal Bones:
12 pairs of ribs
7 pairs of “true ribs”
3 pairs of “false ribs”
2 pairs floating ribs
costal cartilage
Rib w/
shaft (body)
tubercle
neck
head
and for review....
Study tips
Here are some points that are useful to keep in mind when learning the skeletal anatomy....
1. Most bone markings are associated with one of the following:
a. attachment points for tendons (muscles) & ligaments (ex: tuberosity, process, ridge)
b. forms part of a moveable joint (ex: condyle, process, fossa, notch)
c. guides blood vessels, nerves, tendons over/through the surface of a bone
(ex. foramen, canal, notch)
2. For appendicular bones, decide which is the anterior surface and which is posterior
surface and whether it is from the right or left side of the body. Knowing R vs L is
essential if you are to correctly identify features indicated as medial or lateral.
3 Recognize that the name of a landmark gives you hints about where it is & what it does.
For example, the olecranon process fits into the olecranon fossa (= your elbow joint)
4. You are not being asked to know any more than any other A and P student.
Axial Skeleton: Vertebrae and Ribs
Part 2:
Appendicular Skeleton = shoulder girdle + pelvic girdle + upper & lower extremities
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