Respiratory system 1 - Intro to thorax Flashcards
What is the thorax?
superior part of the trunk between the neck and the abdomen
What is the thoracic cavity surrounded by?
thoracic cavity (containing heart, lungs, thymus, distal part of the trachea and most of the oesophagus ) surrounded by thoracic wall (containing skin , fascia, nerves, vessels, muscles, cartilages and bones
What is the function of the thoracic wall?
protects the thoracic and also some of the abdominal organs
helps in respiratory movements
acts as a muscle attachment site for various groups of muscles
What is the thoracic cage?
12 pairs of ribs
12 thoracic vertebra with intervertebral discs
the sternum
Costal cartilage role?
form the anterior continuation of the ribs, providing a flexible attachment at their articulation with the sternum
What are the ribs and their cartilages separated by?
intercostal spaces
What are the intercostal spaces occupied by?
these spaces are occupied by intercostal muscles, vessels and nerves
How does the thoracic cavity communicate with the neck?
through the superior thoracic aperture which is also called anatomical thoracic inlet
How doses thoracic cavity communicate with abdomen?
inferior thoracic aperture which is also called the anatomical thoracic outlet
Describe the boundary of the superior thoracic aperture/anatomical thoracic inlet ?
The first thoracic vertebra (T1) posteriorly.
The first pair of ribs laterally.
The costal cartilage of the first rib and the superior border of the manubrium anteriorly.
Describe the boundary of the The inferior thoracic aperture/thoracic outlet?
12th thoracic vertebra posteriorly.
11th and 12th pairs of ribs laterally.
Costal cartilages of ribs 7 through 10 and xiphisternal joint anteriorly
What are the three parts that the sternum consists of?
manubrium, body and xiphoid process
What is on each side of the manubrium?
clavicular notch
What does the clavicular notch form?
articulates with the sternal end of the clavicle and it forms a saddle joint
just below that point the manubrium articulates with cartilage of the first rib and forms a primary cartilaginous joint
What level is the sternal angle at?
level of the second pair of costal cartilages
lies opposite to the fourth intervertebral disc between T4 and T5 vertebra
What level does the trachea bifurcate?
sternal angle
What are the three kinds of ribs?
true ribs
false ribs
floating ribs
What are true ribs?
first to seventh ribs
they are directly connected to sternum
What are false ribs?
8th to 10 ribs
indirectly connected to the sternum
attach to each others cartilages and form the costal margin anteriorly
What are floating ribs?
11th and 12th ribs
Floating because they are not connected to the sternum
Give characteristics of the first rib?
broad and flat
has two surfaces (inferior and superior)
How is the upper surface of the rib marked?
marked by two shallow grooves
separated by a tubercle ( for attachment of anterior scalene muscle)
What does the anterior groove and posterior groove contain?
anterior groove - subclavian vein
posterior groove- subclavian artery and lowest trunk of the brachial plexus
How many articular facets does the first rib have ?
only one unlike other ribs and for the articulation with the body of the first thoracic vertebra
What are the parts of a typical rib?
head (two articular facets, superior and inferior which articulate with two vertebral bodies)
neck
tubercle - hump at the junction of the neck and the body of the rib
body