Thoracic Wall Flashcards
Where a major site for red blood cell production (bone marrow) in the thoracic wall?
Sternum
What is the widest and thickest part of the sternum?
Manubrium
What does the upper border of the manubrium form?
Jugular notch
The body of the sternum articulates with what?
Second to seventh costal cartilages
Which costal cartilage articulates directly with the manubriosternal joint?
Of the second rib
What part of the sternum is sometimes broken during CPR?
Xiphoid process
Which part of the sternum is cartilaginous at birth & slowly ossifies throughout life?
Xiphoid process
What variation of the xiphoid process is fairly common?
Being bifid
Which variation of the xiphoid process is rarely present?
Xiphoid foramen
What is formed by the articulation of the manubrium with the body of the sterum?
Sternal angle
At what vertebral levels is the sternal angle found?
T4 and T5
What is “barrel chest”?
More pronounced sternal angles
Barrel chest is common among what condition?
Chronic Obstructive Pulmonary Disease (COPD)
What is another name for the thoracic inlet?
Superior thoracic aperture
What are the three boundaries of the superior thoracic aperture (thoracic inlet)?
Manubrium, first rib, and first thoracic vertebra
What is another name for the thoracic outlet?
Inferior thoracic aperture
What are the five boundaries of the inferior thoracic aperture?
Xiphoid process, costal margin, twelfth rib, distal end of the eleventh rib, twelfth thoracic vertebra
Which are the “true ribs”?
1-7
Where do the true ribs articulate?
Directly with the sternum through their own costal cartilages
Which are the “false ribs”?
8-12
Where do ribs 8-10 articulate?
Indirectly with the sternum by attaching to the costal cartilage of the rib above
Where do ribs 11 and 12 articulate?
They don’t articulate with the sternum at all :) Known as “floating ribs”
Which are “typical ribs”?
3-9
Which are “atypical ribs”?
1, 2, 10, 11, and 12
What shields the intercostal vein, artery, and nerve of a typical rib?
Costal groove
What are the three functions of the thoracic cage?
Protection of thoracic and upper abdominal organs, muscle attachments, and respiration
What is the second most important muscle for respiration?
External intercostal muscle
What is the origin of the external intercostal muscle?
Lower border of ribs 1-11
What is the insertion of the external intercostal muscle?
Upper border of ribs 2-12
What is the nerve supply of the external intercostal muscle?
Corresponding intercostal nerve
What is the function of the external intercostal muscle?
Elevates the ribs in inspiration
How do the fibers run in the external intercostal muscle?
Downward and forward (hands in pockets)
Where does the external intercostal muscle begin and end?
Begin at tubercle of rib, end at costochondral joint
What replaces the external intercostal muscle where it ends?
External intercostal membrane
What is the origin of the internal intercostal muscle?
The upper border of ribs 2-12
What is the insertion of the internal intercostal muscle?
The lower border of ribs 1-11
What is the nerve supply for the internal intercostal muscle?
Corresponding intercostal nerve
What is the function of the internal intercostal muscle?
Depresses the ribs in FORCED expiration