The thorax Flashcards
main external anatomical features of the thorax
sternum, ribs, inlet, outlet
thoracic inlet is bounded by
first thoracic vertebrae, first pair of ribs, costal cartilage of front rib and superior border of manbrium
thoracic outlet is bounded by
12th thoracic vertebra, 11th and 12th pairs of ribs, costal cartilage of ribs 7-10 and the xiphisternal joint
Which bones articulate with the manubrium at its superolateral angles?
collar bones, first set of ribs
What type of joint is the sternoclavicular joints
synovial saddle
What is the name given to the median notch formed by the superior border of the manubrium?
jugular notch
At what vertebral level is the xiphoid process usually located?
t10
Facets for 2nd costal cartilage. With which parts of the sternum do these articulate?
manubrium
The head of rib 5 articulates with the bodies of which vertebrae?
t4 and t5
What part of a vertebra articulates with the rib tubercle?
costal facet on transverse process of posterior vertebrae
Which ribs are true ribs (vertebrosternal)
1-7
Which ribs are floating ribs (vertebral)?
11-12
Which ribs are false ribs (vertebrochondral)?
8-12
on first rib where is the groove for subclavian vein
closer to neck than groove for subclavian artery
Which part of a rib articulates with these demi-facets?
head
A single typical rib articulates with two vertebral bodies and one vertebral transverse process. These are:
- the vertebral body of the same number as the rib
- the vertebral body immediately above
- the vertebral transverse process of the same number as the rib
Which ribs/costal cartilages form the costal margin and the subcostal angle?
7th-10th ribs
where does sternal angle lie
at manubriosternal joint
what makes 1st rib different
broad and flat, one single articular facet, upper surface of body is marked by two shallow grooves separated by scalene tubercle
typical rib features
two articular facets, head, neck, costal groove, tubercle
where does head of rib articulate with body of thoracic vertebrae
costovertebral joints (at side of body between two vertebrae)
three layers of intercostal muscles
external, internal, innermost
order of neuromuscular bundle
VAN - vein artery then nerve top to bottom
In which part of a rib is the neurovascular bundle lodged
costal groove
Between which two intercostal muscles is the neurovascular bundle located?
innermost and internal
arterial supply to the thoracic cage is from
posterior intercostal arteries (from thoracic aorta), anterior intercostal arteries (from thoracic artery), branch of axillary arteries
venous drainage from thoracic cage
azygos, hemiazygos accessory hemiazygous venous system and internal thoracic veins
the breast lymphatic drainage
axillary lymph node, parasternal lymph node, abdominal lymph node
what dermatomes work on thorax
T3-T12
what is area in thoracic cage called
mediastinum
where does transverse thoracic plane lie
between T4 and T5 and the manubriosternal joint
attachments of the diaphragm
lumbar vertebrae, costal cartilages of ribs 7-12, xiphoid process of the sternum, central tendon
what are the right and left crura
the parts of the diaphragm that arise from the vertebrae and are tendinous in structure
where does right crus come from
arise from L1-L3 (some surround oesophageal opening and help prevent reflux)
where does left crus come from
arises from L1-L2 and their intervertebral discs
action of diaphragm
contracts during inspiration (flattens), relaxes during expiration
hiatuses (openings) of diaphragm
T8- canal opening for inferior vena cava and right phrenic nerve, T10- oesophageal hiatus for oesophagus and vagus nerves, T12- aortic hiatus for aorta, azygos vein, hemiazygous vein, thoracic duct
phrenic nerves are sensory/motor/mixed
mixed
nerve roots of phrenic nerves
anterior rami of C3, C4 and C5
motor functions of phrenic nerves
pierces and innervates the diaphragm from its inferior surface
sensory functions of phrenic nerves
supplies the central part of the diaphragm
