Thorax Flashcards
Right dome of the diaphragm
can rise to the level of the upper border of the 5th rib
Left dome of the diaphragm
can rise to the level of the lower border of the 5th rib
central tendon
peripheral muscular fibres of the diaphragm attach to the inferior margin of the thoracic cage and the lumbar vertebrae, then converge on the central tendon
right crus
muscular extension of the diaphragm, originates from the anterolateral surface of the upper 3 lumbar vertebrae
left crus
muscular extension of the diaphragm, originates from the anterolateral surface of the upper 2 lumbar vertebrae
caval opening
in central tendon at T8 is an opening for the IVC (IVC situated in the posterior thorax on the right side)
esophageal opening
in the right crus at T10 is an opening for the esophagus
where is the esophagus in relation to the thoracic aorta
the esophagus deviates left as it descends through the thorax, lying anterior to the thoracic aorta
aortic hiatus
between the right and left crus anterior to T12 is the opening for the abdominal portion of the aorta (located on the left side of the posterior thorax)
external intercostals
fibres run anteroinferiorly from the lower border of the rib
internal intercostals
fibres run posterosuperiorly from the upper border of the rib
manubriosternal joint (sternal angle)
the inferior border of the manubrium articulates with the superior part of the sternal body at the manubriosternal joint – in line with T4&T5
xiphisternal joint
the xiphoid process attaches to the sternum at the xiphisternal joint – in line with T9
internal thoracic arteries
- lateral to sternum
- main blood supply of the anterior thoracic wall
where do the posterior and anterior intercostal arteries originate from?
the thoracic aorta and internal thoracic arteries give rise to pairs of posterior and anterior intercostal arteries
subcostal arteries
12th pair of arteries in intercostal space, run inferior to costal margin compared to intercostal arteries
venous drainage of the thorax
parallels arterial supply – internal thoracic veins
where do the anterior intercostal, posterior intercostal and subcostal veins go?
they drain deoxygenated blood into the heart
intervertebral discs
- between vertebral bodies
- consist of annulus fibrosus and a central nucleus pulposus
- act as shock absorbers
annulus fibrosis
- outer ring of disc made up of fibrocartilage
- resists sheer forces
nucleus pulposus
gelatinous structure that functions to resist compressive forces
herniated disc
- intervertebral discs do not come in contact with the contents of the intervertebral or vertebral foramens except if there is structural damage to the disc (ie. herniated disc)