THORACIC WALL Flashcards
Special feature of 1st rib
grooves for subclavian artery and vein
True ribs attach to directly sternum via
costal cartilages
False ribs attach indirectly to sternum via
7th costal cartilage
Most common site of rib fractures
at angle of rib (sharpest part of curvature)
Are smaller or larger ribs most commonly associated with rib fractures?
larger
Major risk factor of rib fractures
May injure nearby structures (lungs/pleura/spleen/liver)
Intercostal Space
space between ribs
Contents of Intercostal Space
Intercoastal muscles (x3 - external, internal, innermost), intercostal VAN
Opposite from vertebral levels T2-T4
Manubrium (sternum)
Opposite from vertebral levels T5-T8
body of sternum
Opposite from T4/T5 vertebral disc
Sternal Angle
Why is sternal angle an important anatomical landmark?
o Marks start and endpoint of aortic arch
o Divides superior and inferior mediastinum
o Level of bifurcation of trachea
o Location of 2nd rib
Important clinical correlate for Sternum
Sternotomy in Heart Surgery (open the sternum)
Thoracic inlet
top “hole” of ribcage
Thoracic outlet
bottom “hole” of ribcage
Structures passing through THORACIC INLET
major arteries off aorta, major veins to SVC, trachea, esophagus, phrenic n., Vagus n.
Structures passing through THORACIC OUTLET
IVC, aorta, esophagus, sympathetic nn., Vagus nerve plexus
Parietal Pleura
thin CT forming deepest layer of thoracic wall
PARIETAL PLEURA is intimately associated with
Visceral Pleura on lungs
Costodiaphragmatic Recess
cavity along inferior margins of thoracic space
Costodiaphragmatic Recess is created by
dome of diaphragm protruding into thoracic space
Costodiaphragmatic Recess structure pattern
Shallow anteriorly getting progressively deeper as runs lateral then posteriorly
Pectoralis Major
Large fan-shaped muscle, running from humerus to sternal margin
Pectoralis Minor
small muscle immediately deep to pectoralis major, running from coracoid process to ribs
Pectoralis Minor Nerves
Medial and Lateral Pectoral Nerves
External Intercostal Muscles
most superficial layer
External Intercostal Muscle fibers direction
inferoanterior direction (\\\\ ///////)