Exam 2 Flashcards
(110 cards)
diaphragm
principle muscle for inspiration
diaphragm origin
lower perimeter of rib cage (ribs 7-11), xiphoid process of sternum, body and transverse processes of upper four lumbar vertebrae, rising to an elevated central tendon.
diaphragm insertion
central tendon.
diaphragm action
flattens, drives central tendon inferiorly, inhalation. increase the volume of thorax and thus create inward air flows and negative pressure
changes. inspiration action.
external intercostals
superior attachment is nearer the vertebral end than the inferior attachment. (angled appearance allows ribs to be raised)
external intercostals origin
superficial inferior margin of ribs 1 - 11
external intercostals insertion
superficial superior margin of rib below.
external intercostals action
raise the ribs
- result is a superior and anterior movement of ventral ribs and sternum
- results in an increase in total lung volume
- contraction moves ribs to a more horizontal position, like blinds
Internal Intercostals Interchondral
lie deep to externals
Internal Intercostals Interchondral origin
deep inferior margin of ribs 1 – 11 within the
region of the costal cartilages.
Internal Intercostals Interchondral insertion
deep superior margin of rib below.
Internal Intercostals Interchondral action
muscle exerts upward pull to raise the ribs.
Levator Costarum origin
transverse process of C7-T11.
Levator costarum insertion
Course downward into sub-adjacent rib.
Levator Costarum action
Slight elevation of posterior rib cage.
serratus posterior superior origin
Spinous Process C7-T3
serratus posterior superior insertion
Courses own to insert into angle of ribs 2-5.
serratus posterior superior action
Elevate ribs 2-5.
Thoracic muscles of expiration
cause a decrease of lung volume that basically moves air out
Transversus Thoracis
on the underside of rib cage
Transversus Thoracis origin
deep surface of the sternum
Transversus Thoracis insertion
costal cartilages above its point of origin
Transversus Thoracis action
lowering of costal cartilages 2 through 6
serratus posterior inferior origin
spinous processes of T10-12 and L1-3.