Download Chapter 7 Axial Skeleton

LECTURE OUTLINE CHAPTER 7 Marieb
The Skeletal system: Axial division
Lecture Outline
I. AXIAL SKELETON
A. Structures
1. sutures
a. coronal - between frontal and parietal bones
b. lambdoidal - between occipital and parietal bones
c. sagittal - between two parietal bones
d. squamosal - between temporal and parietal bones
2. skull
a. cranium - brain case
1) occipital - landmark - foramen magnum
i. occipital condyles- articulate with atlas
ii. occipital crest
iii. external occipital protuberance - bump to
lean your head against
iv. nuchal lines - inferior and superior - muscle
attachments
v. jugular foramen
vi. hypoglossal canals
2) parietal - landmark squamosal suture
i. temporal lines - superior and inferior
ii. parietal eminence
3) frontal - landmark - orbital area
i. metopic suture -remnant of fusion between
bones
ii. frontal squama
iii. suprorbital margins
iv. supraorbital foramen/ notch
v. superciliary arch- behind eyebrows
vi. lacrimal fossa
vii. frontal crest
viii. frontal sinus
4) temporal bones (2), landmark - external acoustic
meatus
i. squama
ii. zygomatic process -reaches toward
zygomatic bone
iii. zygomatic arch
iv. mandibular fossa - articulation with
mandible
v. tympanic portion - contains ear
vi. external auditory canal
vii. mastoid process - hard lump behind ear
viii. mastoid foramen
ix. styloid process - sharp pointy process
x. stylomastoid foramen
xi. jugular foramen
xii. carotid canal
xiii. foramen lacerum
xiv. auditory tube
xv. petrous portion - rock hard, inside
xvi. internal acoustic canal - exit for nerve
5) sphenoid i. sella turcica -which contains the pituitary
ii. hypophyseal fossa
iii. anterior clinoid processes
iv. tuberculum sellae
v. dorsum sellae
vi. posterior clinoid processes
vii. optic groove - optic nerves cross here
viii.. optic canal - passage for optic nerve
ix. superior orbital fissure
x. foramen rotundum
xi. foramen ovale
xii. foramen spinosum
xiii. greater wings
xiv. sphenoidal spine
xv. pterygoid process
xvi. pterygoid canal
6) ethmoid - landmark - crista galli
i. cribriform plate - opening for olfactory nerve
ii. crista galli - tiedown for meninges
iii. lateral masses - bulk of bone
iv. superior nasal conchae
v. middle nasal conchae
vi. ethmoidal sinuses - spaces in masses
vii. perpendicular plate - meets vomer to form
nasal septum
b. facial bones
1) two nasal - form bridge of nose
2) two maxillae
i. orbital rim
ii. frontal process - reaches toward frontal bone
iii. alveolar process - sockets for teeth
iv. inferior orbital fissure
v. infraorbital foramen
vi. maxillary sinus
vii. palatal process - horizontal, roof of mouth
viii. hard palate
ix. incisivie foramen
3) mandible
i. body
ii. ramus
iii. coronoid process - highest point
iv. mental foramen
v. mandibular notch
vi. alveolar process - sockets for teeth
vii. mylohyoid line - muscle attachment
viii. mandibular foramen - inside ramus
ix. mandibular canal
4) two zygomatics – cheek bones
5) two palatines
6) two lacrimals
7) vomer - inferior portion of nasal septum
8) two inferior conchae
c. hyoid – no articulations
d. three pairs of auditory ossicles – malleus, incus & stapes
e. sinuses –
i. paranasal – all open into nasal cavity
a) frontal
b) ethmoid
c) sphenoid
d) maxillary
ii. sealed
a) mastoid sinus
B. Fetal skull - many bones separate for growth and birth
1. fontanels
a. frontal ( anterior) - between 2 frontal s and 2 parietal
b. posterior (occipital) - between occipital and parietals
c. pair anteriolateral (sphenoid) - between parietals,
sphenoid, and temporals
d. pair posteriolateral (mastoid) - between temporal,
occipital, and parietals
C.. Spinal column
1. regions
a. cervical 1-7 have transverse foramina
C1 – atlas, no centrum, articulates w/ occipital bone
superiorly and axis inferiorly.
C2- axis – has a superior process, the dens, around
which the atlas articulates in a side-to side motion.
C7 - has long straight spinous process (vertebral
prominens)
b. thoracic – 1-12, ribs attached, will have costal facets for
ribs
c.. lumbar – 1-5
large, blocky spinous processes
d. sacrum 1-5 fused into one block
e. coccyx – 1-3/5 sections, partially fused
2. curvatures - normal
a.. primary – the direction of a fetal spinal curvature,
concave anteriorly
1). thoracic
2). sacral
b. secondary – convex anteriorly, develop later in
development,
1). cervical - develops when able to hold head up
2). lumbar - develops when able to stand
3 curvatures – abnormal
a. scoliosis – lateral curvature mainly in thoracic region
b. kyphosis – exaggerated thoracic curvature, “hunchback”,
„dowager‟s hump”
c. lordosis – exaggerated lumbar curvature, “swayback”
4.. vertebrae features
a. body , centrum
b. neural arch made up of lamina and pedicles
c. neural foramen/ vertebral foramen – surrounded by
centrum and neural arch.
d. processes
i. spinous – unpaired
ii. transverse – paired
iii. superior articulating – paired
iv. inferior articulating - paired
D. Ribs and Sternum
1. 12 pairs of ribs
a. 7 pairs true- each attach to sternum by cartilage
b. 5 pairs false
i. 3 just false - attach indirectly to sternum
ii. 2 pair floating - no sternal attachment
2. sternum
a. manubrium
b. body
c. xiphoid