4.2.3 Thoracic Wall and Lung Cavities Flashcards
Identify the structures.
Where is the thorax located?
B/t the neck and abdomen
What are the key skeletal elements of the thorax?
12 thoracic vertebrae
12 ribs and costal cartilages
1 sternum
What are the components of the sternum?
Manubrium, body, xiphoid process
What are the three types of ribs? Which ribs belong to each of these classifications?
True ribs (1-7): attach directly to sternum
False ribs (8-10 or some say 8-12): costal cartilages do not directly attach to sternum)
Floating ribs (11-12): lack costal cartilage
Which ribs are included in the typical ribs? What are there four common structures?
3-9
Head, tubercle, shaft/body, and angle of rib
What is the most frequent site of rib fractures?
Just lateral to the angle of the rib
How many facets does the head of true ribs have?
2, a superior and inferior facet
What are these components of the ribs?
The scalene tubercle in the 1st rib is the site of attachment for which muscle?
anterior scalene m.
What is another name for the sternal angle?
Angle of Lewis
If which structure is left intact, will it allow for possible regeneration of the rib?
Periosteum
Where is the 13th rib usually located?
On C7
about 0.5 to 1% of the population has a cervical rib
What is circumscribed in green? What is the dense fibrous band connecting it to?
The cervical rib; the dense fibrous band is connecting it to the 1st rib
What condition is associated with the presence of the cervical rib?
Venous Thoracic Outlet Syndrome
(Fun fact: Your fellow classmate THE Miles Sanderson had this syndrome, which led to a blood clot in his shoulder.)
Where do the ribs 1-7 articulate with the stenurm?
What 4 bodily landmarks occur at the level of the sternal angle (the junction of the manubrium with body of sternum)?
Attachment of the 2nd rib
intervertebral level at disc b/t T4 and T5
bifurcation of trachea
azygos veins drains into the SVC
Where are the regions of the mediastinum located?
What commorbidity is often associated with pectus excavatum?
Mitral valve prolapse
What is pectus carinatum?
Ridge projecting anteriorly (more rare than excavatum)
In what patient population is pectus carinatum most likely to develop?
11 to 14 y/o pubertal males undergoing a growth spurt
What is the name of the joint between the ribs and its corresponding vertabrae?
Costovertebral joint, it’s a synovial joint b/t head of rib and body of vertebra at a facet or demifacet
The costotranverse joint is a synovial joint b/t what two structures?
tubercle of the rib and the transverse process of the vertebra
In which ribs is the costotranverse joint fairly curved? fairly flat?
Curved: 1-7
Flat: 8-12
What type of joints are the sternocostal joints?
Cartilaginous
What is costochondritis? In what population is it most common?
Chest pain due to inflammation of the cartilage and bones in the chest wall.
Overuse injury in athletes
What the three layers of the intercostal muscles?
External, internal, and innermost
The external runs down and medial on both sides (like putting hands into front pockets), and the internal and innermost run direction 90 degrees to that
Where do the intercostal nerves run?
Between the internal and innermost intercostal muscle (b/t I and I)
What is different about the subcostal muscles?
They “skip” a rib
Found on the posterior portion of thoracic wall
Where does the pectoralis major originate and insert? pectoralis minor? serratus anterior muscle?
Where are the lateral cutaneous and anterior cutaneous branches given of the intercostal nerves?
Which vein seperates the pectoralis major and the deltoid?
Cephalic vein
Describe the typical positioning of artery, vein, and nerve from cranial to caudal under the groove of each rib?
VAN
V: vein
A: artery
N: nerve
What is shingles?
A reactivation of a latent herpes varicella-zoster viral infection
What is a dermatome? Where are dermatomes C5, T4, T7, T10, L1
An area of the skin which receives innervation from a single spinal nerve.
C5: clavicle
T4: “teat”, nipple
T7: xiphoid process (pointy)
T10: umbilicus (O reminds you of the umbilicus)
L1: inguinal ligament
~75% of the breast is drained into which lymph nodes?
Axillary lymph nodes
What is polythelia? In what population is it most common?
Supernumerary nipple(s) which may appear similar to a mole, anywhere along the mammalian lines (milk lines)
Males
What is polymastia? When is most liked noticed?
Additonal breast along the milk line b/t the axilla and groin.
Rare, most likely noticed at the time of pregnancy due to enlargement and possible production of milk
What is gynecomastia?
Excessive development of the male mammary gland
What is contained in the mediastinum?
heart, great vessels, trachea, esophagus, and thymus
Which muscle acts as the principal muscle of inspiration?
Diaphragm
The are two pectoral nerves? Which pectoralis muscles do they innervate?
Lateral and Medial Pectoral Nerve
Medial pectoral nerve innervates both the major and minor pectoralis
Lateral pectoral nerve only innervates the pectoralis major
