Ribs Flashcards
Who do you name a rib?
by the superior costovertebral joint
Where is the axis of rotation for the rib?
Through the costotransverse joint and the superior costocorporeal joint
During inspiration the vertical diameter of the thorax is increased by..?
the contraction and subsequent lowering of the dome of the diaphragm muscle
How does the shaft of the ribs move during inspiration?
perpendicular to the axis of rotation that courses between the costotransverse and costocorporeal joints
How is expiration defined in terms of motion?
Rib flexion (thoracic flexion aids in forced expiration), closing, internal rotation, and downward motion
What are the primary muscles of inspiration?
The diaphragm, scalene, and intercostals
During inspiration, what direction of expansion does the elevation of the ribs cause?
Expansion AP and ML diameters
What does contraction of the diaphragm cause in terms of expansion of diameters?
Expansion of AP, ML and vertical diameters of the thorax
How is inspiration defined in terms of motion?
Rib extension (thoracic extension)/ opening/ upward motion
What happens to the rib head and tubercle during inspiration?
They move downward
What happens during right lateral flexion?
- Right rib flexion/closing
- Left rib extension/opening
- Left rotation will most likely occur
Boyle’s Law - At fixed temperature and mass, volume and pressure are [directly/inversely] proportional to each other.
inversely; the more capacity we have to depress, the more ability we have to draw in air
The contraction of the primary muscles of inspiration increase the volume of the thoracic cavity. What is happening to pressure in the alveoli and what is the result?
Pressure is decreasing, which results in air being drawn into the lungs
True or False:
In a healthy person, quiet exhalation is primarily a passive process.
True
What happens to the diaphragm during inspiration? during expiration?
Diaphragm contracts and lowers; diaphragm relaxes and recoils upward
[Internal/ External] intercostals help with inhalation while [internal/ external] intercostals help with exhalation.
External; internal
Do the upper or lower six ribs have more motion during breathing?
Lower 6; upper have 23-35 degrees of motion while the lower have 35-45 degrees
Downward slope of ribs rotate ______ and _______ increasing intrathoracic volume in both A-P and M-L directions.
Upward; outward
What changes occur during A-P and M-L during changes in intrathoracic volume?
- Elevation and depression of ribs and sternum
- Lower 6 ribs have motion similar to bucket handle
- Upper 6 ribs have motion similar to a pump handle
- Motion twists cartilage
- Forced inspiration adds thoracic extension motion
Upper rib motions facilitate the _____ and ______ motion of the sternum.
Upward; forward
What happens during expiration?
- Muscles of inspiration relax
- Ribs and sternum return to pre inspiration position
- Decrease in A-P and M-L diameters of thorax
- Rib cartilage uncoils
- Forced expiration combines thoracic flexion motion
Diaphragm: the _______ part arises from upper margins of lower 6 ribs. The ______ part arises from posterior side of xiphoid process. The ______ part is attached to bodies of upper 3 lumbar vertebrae.
Costal; Sternal; Crural
How much work does the diaphragm do for inspiration?
60-80%
Decent of diaphragm is resisted by increase in __________. ____________ provides stabilization so diaphragm can elevate lower ribs.
Intra-abdominal pressure; Abdominal resistance
What does bilateral contraction of the scalene muscles provide?
Elevation of the upper ribs and sternum
What are the 3 layers of intercostals?
- Externi
- Interni
- Intimi
interni fibers run perpendicular to externi fibers
True or false:
Multiple muscles are recruited for forced inspiration by healthy individuals to increase rate and volume of inspired air, or these muscles are recruited to help compensate for weakness, fatigue, or reduced function of primary inspiration
True
What muscles aid in forced expiration?
- Four abdominal m’s
- Transversus thoracis
- Interosseous fibers of internal intercostals
Where are the transverses thoracic muscles located?
internal anterior thoracic wall
The space from the top of the diaphragm to the insertion of the diaphragm.
Zone of Apposition (ZOA)
What happens to the ZOA as you breath in? Breathe out?
Decreases zone; increases zone
With an overactive pelvic floor, the ZOA [increases/decreases}. What does this do to intra-abdominal pressure and inhalation?
increases; increased pressure; harder to inhale
What becomes overactive when the diaphragm is underactive?
The thoracolumbar extensors, upper abdominals, piriformis, and hamstrings
-basically, overactive thoracolumbar extension to help with inhalation
What happens to inhalation when the abdominal wall is weak?
Exhalation becomes more difficult due to thoracolumbar extensors being overactive
If you are in a flexed position, breathing [in/out] will be more difficult while being extended will create more difficulty in breathing [in/out].
In/ out
