Ch. 10 Bony Thorax - Sternum and Ribs Flashcards
main function is to serve as an expandable bellows-like chamber, wherein the interior capacity expands during inspiration and contracts during expiration
bony thorax
what does the bony thorax consists of
- sternum anteriorly
- thoracic vertebrae posteriorly
- 12 pairs of ribs connecting the sternum to the vertebral column
a thin, narrow, flat bone with 3 divisions
sternum
what are the 3 divisions of the sternum
- manubrium
- body
- xiphoid process
total length of the adult sternum
about 7” (18 cm)
what type of bone does the sternum consists of
highly vascular cancellous tissue covered by a thin layer of compact bone
this allows for the sternum to be a common site for marrow biopsy
vascular cancellous tissue
under local anesthesia, a needle is inserted into the medullary cavity of the sternum to withdraw a sample of red bone marrow
marrow biopsy
upper portion of the sternum
manubrium
how long is the adult manubrium
2” (5cm)
longest part of the sternum
body
how long is the body of the sternum
4” (10cm)
at birth, the body of the sternum is in how many separate segments
4
when does the union of the segments of the body of the sternum take place
starting at puberty and complete possibly at age 25
most inferior portion of the sternum
xiphoid process
what is the xiphoid process composed of during infancy and youth
cartilage
when does the xiphoid process become totally ossified
40 years
these are the true ribs
1-7
these are ribs that connect directly to the sternum with a short piece of carilage
true ribs
what is the short piece of cartilage that connects the ribs to the sternum called
costocartilage
these are the false ribs
8-12
these have costalcartilage that joint together at the costocartilage of rib 7
false ribs - 8-10
these are floating ribs because they do not connect to the sternum
11 and 12
these ribs do not possess costocartilage
11 and 12
what is the posterior end of a rib called
vertebral end
what is the anterior end of a rib called
sternal end
what does the vertebral end of a rib consists of
head and flattened neck
lateral to the neck of the rib is this which articulates with the transverse process of a vertebra and allows for attachment of a ligament
elevated tubercle
how does the body of the rib extend from the tubercle
laterally and then angles forward and downward
what is the area of forward angulation termed
angle of the rib
the part at which the shaft of the rib curves forward and downward toward the sternal end
angle of the rib
how much higher is the vertebral end of a rib compared to the sternal end
3-5” (8-13 cm) higher
the lower inside margin of each rib protects this
an artery, a vein, and a nerve
rib injuries may be associated with this
substantial hemorrhage
inside margin, which contains the blood vessels and nerves is called this
costal groove
these are the most vertical ribs
first ribs
the ribs get longer as you go down starting with the first, but starting at this rib they get shorter
7th rib down
these are the most sharply curved ribs
first ribs
the bony thorax is typically widest at the lateral margins of these ribs
8th or 9th
what are the two other names for the jugular notch
- manubrial notch
- suprasternal notch
what level is the jugular notch at
T2-T3
this is where the lower end of the manubrium joins the body of the sternum
sternal angle (manubriosternal joint)
what level is the sternal angle at
intervertebral disk space between T4-T5
what level is the xiphoid process at
T9-T10
what level is the inferior costal margin at
L2-L3
each clavicle articulates medially with this at the clavicular notch
manubrium
what is the articulation between the clavicle and the manubrium called
sternoclavicular joint
this is the only bony connection between each shoulder girdle and the bony thorax
sternoclavicular joint
how many facets does the sternum contain
7 pairs located laterally along the manubrium and the body
where is the first pair of facets located in relation to the clavicular notch
just below the clavicular notch
where do the second costocartilage connect to the sternum
level of the sternal angle
these connect directly to the body of the sternum
3rd-7th rib
joint between the costocartilage and the sternal end of a rib
costochondral union/junction
what type of joints are costochondral unions classified as
synarthrodial, unique union - bound together by the periosteum of bone itself
what type of joint is the sternoclavicular joint
synovial - plane (gliding), diarthrodial
what type of joint is the sternocostal joint of the first rib
synarthrodial, cartilaginous joint
what type of joint is the sternocostal joints of 2-7 rib
synovial - plane (gliding), diarthrodial
joint between costocartilage and sternum
sternocostal joint
continuous joint between costal cartilages of the anterior 6th-9th ribs
interchondral joints
what type of joint are the interchondral joints between the 6th-9th costocartilage
synovial - plane (gliding), diarthrodial
what are the interchondral joints between the 9th and 10th cartilages classified as
fibrous - syndesmosis
what type of joints are the costotransverse joints
synovial - plane (gliding)
what type of joints are the costovertebral joints
synovial - plane (gliding)
which ribs are the costotransverse joints found on
1st-10th
instead of an AP/PA of the sternum, how do you visualize the sternum
rotate patient into a 15-20 degree RAO position
a patient with a shallow or thin chest requires how much rotation when visualizing the sternum
more rotation - 20 degrees
a patient with a deep chest requires how much rotation to visualize the sternum
less rotation - 15 degrees
what is the sternum primary made up of
spongy bone
for adult, sthenic patients, what is the kVp range for sternum
70-85
what is the breathing technique for a sternum projection
orthostatic breathing
to minimize dose to the patient, the patient’s skin should be how far from the surface of the collimator
at least 15” (40 cm)
are sternoclavicular joints typically performed AP or PA
PA
these represent the minimum number of ribs above the dome or central portion of the diaphragm on full inspiration
upper 9 posterior ribs
to visualize the ribs above the diaphragm what should the tech do
position patient erect if possible and take on inspiration
to visualize the ribs below the diaphragm what should the tech do
position the patient recumbent and take on expiration
what are the preferred projections for someone with history of trauma to the left posterior ribs
AP and an LPO
what are the preferred projections for a patient with trauma to the right anterior ribs
PA and an LAO
