Chapter 14 The Axial Skeleton
How many thoracic vertebra do we have?
12
How many vertebrae are in the spinal cord
33
normal curvatures of a spine
4, thoracic and sacral convex posterior (primary curvatures), cervical and lumbar convex anterior (secondary curvatures)
How many coccyx vertebra do we have?
4-5
How many lumbar vertebra do we have?
5
How many sacrum vertebra do we have?
5
How many cervical vertebra do we have?
7
how do false ribs attach
8-10 attach to the costal cartilage of the rib superior, and 11-12 do not attach to the sternum (floating ribs)
Identifying characteristics of a cervical vertebra
Bifid spinous process (divides into two); transverse foramina
where is the curve of the spine in lordosis
anterior lumbar
Another name for the first cervical vertebra
atlas (C1)
Another name for the second cervical vertebra
axis (C2)
atlantoaxial joint
between atlas (C1) and axis (C2), pivot joint that allows you to perform the no movement with your head
parts of a typical vertebrae
body, vertebral arch, pedicle, lamina, spinous process, articular facet, transverse process
which vertebrae becomes erect when an infant begins to hold his/her head up
cervical
which vertebrae are secondary curves
cervical and lumbar
which vertebrae do not become apparent until several months after birth
cervical and lumbar
What is the order of the vertebra
cervical, thoracic, lumbar, sacrum, coccyx
Lamina on a typical vertebra
closest to spinous process
Pedicle on a typical vertebra
closest to the body
what do the 4 coccygeal vertebrae fuse to form
coccyx
how do true ribs attach
directly to sternum with their own costal cartilage
lordosis
exaggerated convex anterior curve of the lumbar region
kyphosis
exaggerated convex posterior curve of the thoracic region (hunchback--often occurs in elderly)
scoliosis
exaggerated lateral curve of the thoracic or lumbar region (convex to the side)
what is an intervertebral disc
fibrocartilaginous disc found between bodies; compresses to absorb shock
what kind of bone are the ribs
flat
what kind of bone is the sternum
flat
movements permitted at the lumbar vertebrae
flexion and extension, some lateral flexion
movements permitted at the cervical vertebrae
flexion, extension, lateral flexion, rotation (spine region with greatest range of movement)
costal groove
formed by the intercostal nerves, arteries, and veins
How does the body change as we go down the vertebral column
increases in size because it has to hold up more weight
sternoclavicular joint
joint between axial and appendicular skeleton
Which vertebra looks like a moose
lumbar
which vertebrae becomes erect when a child begins to walk
lumbar
3 main parts of the sternum
manubrium (top), body (middle), xiphoid process (bottom point)
where is the Body on a typical vertebra
most anterior
where is the Spinous process on a typical vertebra
most posterior (you can feel it on your back)
Difference in the atlas (1st cervical vertebra)
no body, and no spinous process
Difference in the axis (2nd cervical vertebra)
odontoid process (dens) (point sticking out at the bottom)
describe the pedicles and laminas when going around the vertebral neural arch from the body
pedicle, lamina, lamina, pedicle
are the pedicles or the laminae directly connected to the body of a vertebra
pedicles
what type of joint is that atlantoaxial joint
pivot
what are the spinous processes
places for muscle and ligament attachment
what type of joints do the ribs form when they articulate on the thoracic vertebra
plane (gliding)
where is the curve of the spine in kyphosis
posterior thoracic
function of the vertebral neural arch
protects vertebral foramen (posterior)
functions of the vertebral column
provides bony protection for spinal nerve and cord roots, strong but flexible support for the trunk, important in posture and support of body weight
True ribs
ribs 1-7
false ribs
ribs 8-12
movements permitted at the thoracic vertebrae
rotation and lateral flexion (limited by ribs)
what do the 5 sacral vertebrae fuse to form
sacrum
Identifying characteristics of a thoracic vertebra
sharp, downward pointing spinous process; articular facets for ribs; heart shaped body
Identifying characteristics of a lumbar vertebra
short, blunt spinous process; massive kidney shaped body
major function of c2
skull rotates on it
what are the bones of the axial skeleton
skull, sternum, ribs, vertebrae, sacrum, and coccyx
what passes through the intervertebral foramina
spinal nerves
how do the vertebrae articulate to the head of ribs
superior articular facets
where do the heads of ribs articulate
superior articular facets (thoracic vertebral bodies)
function of the body of a vertebrae
supports body weight (anterior)
major function of c1
supports skull
Which vertebra do the ribs articulate with
thoracic
Which vertebra looks like a giraffe from the posterior side
thoracic
which vertebrae are primary curves
thoracic and sacral
which vertebrae develop during fetal development
thoracic and sacral
where is the curve of the spine in scoliosis
thoracic or lumbar
why is the sacrum less curved in females
to increase the size of the pelvic outlet
what is the dens held together by
transverse ligament
where do the tubercles of ribs articulate
transverse process
when are intervertebral foramina formed
when notches line up between successive vertebrae
xiphoid process
where diaphragm attaches to anterior wall, and landmark for locating superior surface of the liver and the right margin of the heart
sternal angle
where the manubrium meets the body, and where the 2nd rib articulates