Thoracic cavity Flashcards
Ribs
12 pairs:
- 1⇒7: true ribs
- 8⇒10: false ribs, common cartilage connection
- 11⇒12: flating ribs, no cartilage
- have head, neck, body and tubercle
Vertebrae
- 7 cervical
- 12 thoracic vertebrae
- costal fovea
- 5 lumbar vertebrae
- costal process
- accessory process
- mammilary process
- 5 sacral vertebrae
- 4 Coccyx
Inervertebral disk
- annulus fibrosus: outer fibrous part, ring of fibrocartilage
- nucleus pulposus: central gelatinous soft fibrocartilage
Ligaments of vertebrae
- anterior longitudinal ligament
- posterior longitudinal ligament
- ligamenta flava
- interspinous ligaments
- suprasinous ligaments
- intertransverse ligament
Joints of thoracic cage
- joint of head of ribs
- costotransverse joints
- costochondral joint
- interchondral joint
- sternocostal joint
External intercostal muscles
- 11 pairs
- tubercle of ribs posteriorly ⇒ costochondral junction anteriorly
- fibers from up, lat ⇒ down, med
- function: contract during inspiration, elevate ribs
Internal Intercostal muscles + innermost intercostal
- 11 pairs
- fibers from superioanteriorly ⇒ down
- sternum ⇒ angle of ribs posteriorly
- function: depresses ribs during expiration, elevates ribs during inspiration
Subcostal muscles
- in posterior lateral thoracic wall
- extend across more than 1 IC space
- function: expiration
Nerves of thoracic wall
12 pairs of thoracic spinal nerves ⇒ anterior and posterior ramus
- Posterior rami ⇒ medial and lateral branch ⇒ muscles of the back
- Anterior rami ⇒ run along extent of intercostal spaces⇒ give cutaneous branches
Vasculature of thoracic wall
- from thoracic aorta, subclavian artery an axillary artery
- each IC space has: large posterior IC artery + small pair of anterior IC arteries
- veins: supreme IC veins (⇒ brachiocephalic vein) + superior IC veins (⇒ azygos/hemiazygos)
Parts of Diaphragm
- muscular part
- sternal
- costal
- lumbar - tendinous part
Caval opening of diaphragm
T8/T9
IVC + right phrenic nerve
Esophageal hiatus of diaphragm
T10
esophagus + left and right vagal trunks + left gastric vein
Aortic hiatus of diaphragm
T12
aorta + thoracic duct
Sternocostal triangle of diaphragm
superior epigastric vessel
Intermediate hiatus of diaphragm
sympathtic trunk + azygos + hemiazygos vein + greater and lesser splanchnic nerves
Arterial supply of Diaphragm
superior phrenic artery (thoracic aorta)
inferior phrenic artery (abdominal aorta)
musculophrenic + pericardiophrenic arteies (internal thoracic artery)
Innervation of diaphragm
Phrenic nerve (C3-C5)
Position of diaphragm
Midposition: right dome reaches 4th IC space and left dome is in 5th IC space
Maximal Expiration: right dome upper margin of 4th rib, left dome in 4th IC space
Maximal Inspiration: right dome to 6th rib, left dome to 6th IC space
