Thorax

Question 1

Rib Cage

Answer 1

-Thoracic vertebrae T1-T12
-Ribs 1-12
-costal cartilages
-sternum
- manubrium
- body of sternum
- Xiphoid process
-2x Clavicles

Question 2

Ribs: connections

Answer 2

1-10 attach to the sternum anteriorly via costal cartilage (costochondral and costosternal)
and to the vertebrae’s transverse process (costovertebral)

Question 3

True Ribs

Answer 3

-ribs 1-7
-directly connected to the sternum via costal cartiledge
-move anteriorly
-pump handle movement (moving up / increasing anteroposterior volume)

Question 4

false ribs

Answer 4

-ribs 8-10
-indirectly connected to sternum via costal cartilage
-move superiorly and laterally
-bucket handle movement (increase lateral volume)

Question 5

floating ribs

Answer 5

-ribs 11&12
-not connected to sternum

Question 6

Muscles of Thorax: Diaphragm

Answer 6

-primary muscle of inspiration
-attachments to inferior border of the rib cage, xiphoid process, vertebral column and central tendon
-phrenic nerve
-Function: flattens to pull down thoracic cavity, recoils to domed shape (passive recoil) to push thoracic cavity up

Question 7

Muscles of Thorax: External Intercostals

Answer 7

-involves in INspiration
-Attach from rib below to rib above from R12-R1 (11 pairs)
-elevate ribs= increasing size of thoracic cavity

Question 8

Muscles of Thorax: Internal Intercostals

Answer 8

-involved in forced EXpiration
-Attach from rib below to rib above from R1-R12 (11 pairs)
-fibres run opposite to externals
-depress ribs= decrease size and volume of thoracic cavity