Chapter 3: The Thorax Flashcards
what is the superior thoracic aperature open to?
open to the neck
what is the inferior thoracic aperature closed by?
the diaphragm
what are the flexible walls of the thorax formed by?
the musculoskeletal system (ribs, verts, sternum, muscles)
L and R pleural cavities surrounding lungs and mediastinum
thoracic cavity
*one of the most important functions of the thorax
breathing
what parts of the thoracic region are involved in breathing?
diaphragm
thoracic walls
ribs
provides major change in thoracic volume
diaphragm
changes in lateral and anterior dimensions of thorax during breathing
thoracic walls
what does the thorax house?
houses not only lungs, heart, and great vessels but also much of the liver, stomach, and spleen
- acts as a conduit for structures that pass through the thoracic cavity or connect to structures in the thoracic cavity
- houses the heart
the mediastinum
consists of skeletal and muscle elements
thoracic wall
what does the thoracic wall consist of posteriorly?
12 thoracic vertebrae and intervertebral discs
what does the thoracic wall consist of laterally?
ribs and intercostal muscles
what does the thoracic wall consist of anteriorly?
sternum (manubrium, body of the sternum, xiphoid process)
composed of costal cartilage
Anterior (distal) end of ribs
what do ribs articulate with?
thoracic vertebrae
how many articulations do ribs have with vertebral column?
most have 3
are classified as true, false, and floating
ribs
Bordered by vertebrae T1, medial margin of 1st rib, and manubrium
superior thoracic aperature
what is the plane of the thoracic aperture?
oblique
how do the first ribs slope?
inferiorly
what lies on either side of the entrance to the mediastinum at the aperture?
superior aspects of the pleural cavities
what do structures that pass between the thorax and limb pass over?
the pleural cavity and 1st rib
how do structures that pass to the neck go?
pass more vertically