Thoracic Wall and Lungs Flashcards
What are the boundaries of the thoracic inlet?
first thoracic vertebra, medial border of first rib, and their costal cartilages, superior border of the manubrium
Where do the ribs attach to the sternum?
1-7 (true ribs) - costal cartilage attaches directly to the sternum
Where do the ribs attach to the vertebral?
The head of the rib attaches to the vertebral body, tubercle of the rib attaches to the transverse process of the vertebra
What/where is the costal margin?
Lower edge of rib cage formed by the cartilages of the 7th-10th ribs attaching to the sternum
The xiphisternum (diploid process) is not visible why?
The xiphisternum is cartilaginous in the young, with age it ossifies and may fuse to the body in many specimens is not present.
In the living it can be used as a surface landmark for the central tendon of the diaphragm and inferior border of the heart
Which rib attaches at the sternal angle?
The second rib, it can be easily palpated it is used as a starting point when counting ribs
Describe where the head, the tubercle and scale tubercle are
The tubercle is the pointy bit lower down and the scalene tubercle is the inside area of the rib
What muscle is attached to the scalene tubercle?
The anterior scalene muscle
What do the superior articular facet fuse?
Articulate with the inferior articular facets of the vertebra above
The level of the diaphragm varies during ventilation (and between person to person) but that vertebral level does it usually lies during expiration
Level of 5th thoracic vertebra (T5)
What structures pass through the diaphragm and at what level?
inferior vena cava T8
Oesophagus T10
Aorta T12
Where does the diaphragm insert?
central tendon
Which nerve innervates the diaphragm?
The phrenic nerve
Does the diaphragm receive somatic or autonomic innervation?
Somatic
What is the function of the external intercostal muscle?
Moves the ribs outwards, upwards, and forwards during inspiration
What is the function of the internal intercostal muscles?
Draws ribs downwards and inwards during forced expiraiton
What are the 5 accessory muscles of inspiration?
- Pectoralis major
- Pectoralis minor
- Serratus anterior
- Sternocleidomastoid
- Scalenes
Where do the intercostal nerves arise?
From the thoracic region of the spinal cord, they are the ventral rami of the first 11 thoracic spinal nerves
Which structures are supplied by the intercostal nerves?
Intercostal muscles, the parietal pleura, and overlying skin
What type of innervation do the intercostal nerves provide?
Somatic
Where do the posterior intercostal arteries arise?
Thoracic aorta
Where do the anterior intercostal arteries arise?
Internal thoracic (mammary) and musculophrenic arteries
Which system of veins do the intercostal veins drain into?
Azygos system
Where in the body are the apices of the lungs located?
Above the clavicles
What are the major vessels seen at the hilum?
The right primary bronchus, pulmonary veins, and pulmonary arteries
What other structures enter/exit the lungs at the hilum?
Bronchial vessels, lymphatics, autonomic nerves
