Thorax and Diaphragm Flashcards
What is the superior thoracic aperture/anatomical thoracic inlet bound by? (4)
- T1 posteriorly
2, First pair of ribs laterally - Costal cartilage of the first rib anteriorly
- Superior border of the manubrium anteriorly.
What is the inferior thoracic aperture/thoracic outlet bound by? (4)
- T12 posteriorly
- 11th and 12th pair of ribs
- Costal cartilage of ribs 7 through 10 anteriorly
- Xiphisternal joint anteriorly
What does the thoracic cage do?
Protects heart and lungs
`What level is the sternal angle at?
At the lower border of T4 vertebra.
What are the bones of the thoracic cage?
Sternum
12 pairs of ribs
Where does the manubriosternal joint pass through?
T4-5
Describe the structure of the 1st rib.
Broad and flat with it’s surfaces looking upwards and downwards.
What is the one articular facet of the first rib for?
Articulation with the body of the first thoracic vertebra (T1).
What are the two shallow grooves of the upper surface of the first rib separated by?
Scalene tubercle.
What are the two grroves of the upper surface of the body of the first rib for?
Attachment of the anterior scalene muscle.
What does the anterior groove lodge?
Subclavian vein
What does the posterior groove lodge?
Subclavian artery and the lowest trunk of the brachial plexus.
What is any joint between the rib and the vertebra?
Synovial plane joint
What type of joint are the joints between two vertebral bodies?
Secondary cartilaginous.
What does the head of the rib articulate with?
Body of the thoracic vertebra of the same number as well as the body of the vertebra above it.
Name the joint in which the head of the rib articulates with the body of the thoracic vertebra of the same number as well as the body of the vertebra above it.
Costovertebral joint
Costovertebral joints=?
Synovial plane joints.
What does the tubercle of a rib articulate with?
The transverse process of the thoracic vertebra of the same number
Where does the tubercle of a rib articulate w the transverse process of the thoracic vertebra of the same number?
Costotransverse joint
Costotransverse joints=?
Synovial plane joints
What happens to the diaphragm when it contracts?
It goes up (rlly good anatomical vocab here)
Do bucket handle and pump handle movements occur on inspiration or expiration?
Inspiration
Why does bucket handle and pump handle movements occur on inspiration?
To increase volume.
What is the arterial blood supply of the thoracic wall?
Posterior intercostal arteries
Anterior intercostal arteries
Branches of axillary arteries
Describe posterior intercostal arteries
Branch of mainly descending thoracic aorta
Describe anterior intercostal arteries
Branch of internal thoracic artery
List the different opart of the venous drainage system of the thoracic wal.
Azygos
Hemiazygos accessory hemiazygos venous system
Internal thoracic veins
Name the space between ribs.
Intercostal space
List the muscles around the thoracic wall.
External intercostal muscles
Internal intercostal muscles
Innermost intercostal muscles
Subcostalis
Transversus thoracis.
Name the three things under the costal groove of a rib.
Intercostal vein, artery and nerve
Where does the left side of the thoracic wall drain to?
Thoracic duct via left subclavian vein
Where does the right side of the thoracic wall drain to?
Right lymphatic duct via right subclavian artery
How does the breast get drained via the lymphatic system?
cava
What is the dermatome of the nipple?
T4
What divides the mediastinum into the upper and lower mediastinum?
Transverse thoracic plane
Which ribs are in the upper mediastinum?
T1-4
Which ribs are in the lower mediastinum?
T5-T12
Name the three peripheral attachments of the diaphragm.
- Lumbar vertebrae and arcuate ligaments
- Costal cartilage of ribs 7-12
- Xiphoid processes of the sternum
Name the one central attachment of the diaphragm.
Central tendon
Name the parts of the diaphragm which arise from the vertebrae and are tendinous in structure.
Right and left crura
Where does the right crus arise from?
L1-L3
Some fibres from the right crus surround the oesophageal opening. What does this help to prevent?
Reflex of gastric contents back to the oesophagus.
Where does the left crus arise from?
L1-L2 and their intervertebral discs
What is the primary muscle of inspiration?
Diaphragm.
What happens to the diaphragm during inspritaion?
It contracts and descends meaning the domes flatten. This increases the vertical diamter of the thoracic cavaity.
What happens to the diaphragm during expiration?
Diaphragm relaxes and thoracic volume decreases.
Define hiatus.
Opening
List the levels of the three hiatuses of the diaphragm.
T8
T10
T12
What opening is at T8?
Caval opening
Which opening is at the T10?
Oesphageal hiatus
Which opening is at T12?
Aortic hiatus
Describe the caval opening
Passes through the central tendon of the diaphragm
Describe the oesophageal hiatus.
Located through the muscular sling of the right crus
Describe the aortic hiatus.
Between the left and right crus
What does the caval opening transmit?
The inferior vena cava
What does the oesophageal hiatus transmit?
Oesophagus and vagus nerves
What does the aortic hiatus transmit?
Aorta, azygoes vein, hemiazygos vein and thoracic duct
What are the nerve roots of thephrenic nerve?
Anterior rami of C3, C4 (mainly) and C5.
What type of nerve is the phrenic nerve
Motor and sensory
What is the motor function of the phrenic nerve?
Pierces and innervates the diaphragm.
What are the sensory functions of the phrenic nerve?
Supplies the central part of the diaphragm.
What are the peripheral portions of the diaphragm also innervated by?
Sensory fibres of intercostal nerves T7-T12.
- At what vertebral level does the larynx terminate inferiorly, and the trachea begins?
C6
- At what vertebral level does the trachea bifurcate into the left and right main bronchi?
T5 most commonly
What is a true rib?
Rib which directly attaches to the sternum w their costal cartilage
What is a false rib?
Ribs which articulate indirectly w the sternum
What is a floating rib?
A rib which is only attached to the vertebrae.
Which ribs are true?
Ribs 1-7
Which ribs are false?
Ribs 8-10
Which ribs are floating?
Ribs 11 and 12
What are the root values for the intercostal nerves?
hopefully found out at anatomy
