thorax I: thoracic wall & lungs

lecture 10; 01/21

costotransverse joint definition

where the neck of a non-floating rib articulates with the transverse process of the corresponding vertebrae

joints between ribs and vertebrae are _____ joints and allow for ____

synovial plane joints

ribs to elevate and depress with each breath

3 parts of the sternum

manubrium, body, xiphoid process

the manubrium lies at what level

at the level of the 3rd and 4th thoracic vertebrae (T3, T4)

location of the jugular notch

along the superior margin of the manubrium

the manubrium articulates with the ___ and the ____

clavicle, first rib

manubriosternal joint definition + what it forms

the joint between the manubrium and the body

forms the sternal angle

in older people, the manubriosternal joint tends to be ___

fused

the xiphoid process is ___ in younger people and ___ in older people

cartilaginous, ossified

sternal angle definition + significance

the angle formed by the manubriosternal joint

important landmark for level of the disc between T4 and L5; also the level of the 2nd rib

costovertebral joint definition

where each rib articulates, posteriorly, with two thoracic vertebrae

costovertebral joint exception

the first rib articulates with the first thoracic vertebra only

true ribs definition

first 7/8 ribs; they span between the vertebrae and sternum

false ribs definition

usually ribs 8, 9, 10

they are attached to the rib found just superior, and not directly to the sterum

floating ribs definition

ribs 11 and 12

they are suspended in abdominal musculature

costal groove definition/significance

groove at inferior margin of most ribs

helps protect intercostal nerve + vessels

sternocostal joint definition

where ribs are attached to the sternum

interchondral joint definition

where ribs are attached to each other, via costal cartilage

costal cartilage loction

at sternocostal joints and interchondral joints

layers of muscles between each rib

external intercostal, internal intercostal, innermost intercostal muscles

intercostal vein, artery, and nerve location

between the internal and innermost intercostal muscles

usually near inferior margin of rib, in or near costal groove

intercostal vein, artery, and nerve clinical significance

must be careful to not damage when treating a pneumothorax with needle insertion through the intercostal space

diaphragm is innervated by

the phrenic nerve

subcostal nerve definition

what T12 ventral primary ramus becomes

intercostal nerve location

run along the inferior margin of ribs in intercostal space

what the intercostal nerves supply

intercostal muscles + sensory to the strip of skin overlying each intercostal space

thoracic wall is supplied by ___ (arteries)

posterior intercostal, anterior intercostal arteries

posterior intercostal arteries branch from , anterior intercostal arteries branch from _

posterior: aorta

anterior: internal thoracic arteries

superior epigastric artery definition + where they branch from

continuation of the internal thoracic arteries into the abdominal wall

branches of the subclavian arteries

mammary gland location

between pec major muscle, parts of serratus anterior muscle, and the skin

axillary tail definition

wing-like lateral projection of mammary gland

lactiferous duct definition

ducts that drain the mammary glands

difference between non-lactating and lactating women’s breasts/glands

non-lactating women:

• glands and lactiferous ducts are small

• most volume is occupied by fat and suspensory ligaments

breast suspensory ligament fxn

anchor the breast to underlying deep fascia

most breast lymphatics drain into ___

the axillary lymph nodes

breast cancer treatments + prevalence

lumpectomy: surgical excision of cancerous tissue

radical mastectomy: removal of entire breast and underlying pectoral muscles + lymph nodes; now rare

lung pleural sac layers

visceral pleura (inner), parietal pleura (outer)

pleural cavity definition + fxn

space between the pleural membranes, filled with a layer of pleural fluid

reduces friction during respiration; a potential space

there is (negative/positive) pressure in the pleural cavity

negative

the visceral pleura is ___, while the parietal pleura is ____ (innervation)

insensitive to pain

richly innervated

the diaphragmatic pleura and mediastinal pleura are innervated by the ______ (nerve + roots)

branches of the phrenic nerve; C3, C4, C5

the costal pleura is innervated by ___

intercostal nerves

4 parts of a lung

apex, base, root, hilum

the left lung is divided into ______ by the ____

superior lobe and inferior lobe

oblique fissure

the right lung is divided into ___ by _____

superior, middle, and inferior lobe

horizontal fissure and oblique fissure

the left lung has a distinct ____ in its ____ margin

cardiac notch

anterior margin

fissures may be either ___ or ____

incomplete, partly fused

lung apex clinical significance

lung apex is superior to the superior thoracic aperture → trauma to neck (ex. stab wound) can damage the pleura and lung → direct communication b/w atmosphere and pleural cavity

lung root definition

the bundle of structures that enter and leave the lung

lung hilum definition

point at which the root/bundle of structures enters the lung

the lung roots contain ____ and ____

primary bronchi

pulmonary vessels, connective tissue, nerves, and lymphatics

division of primary bronchi after entering hilum

primary bronchi → secondary bronchus → tertiary bronchi

branches of the ____ are closely associated with the bronchi

pulmonary arteries

pulmonary veins are ___ as they leave the hilum, leaving as ____

paired

superior pulmonary vein and inferior pulmonary vein

right vs left lung size difference clinical significance

right primary bronchus is shorter, wider, and more vertical → aspirated objects tend to lodge in middle or inferior lobes

infections and cancer, in the lung, are often limited to one ____

bronchopulmonary segment

lungs receive PNS innervation from the ___ nerve

vagus nerve (CN X)

effect of PNS input on lungs

bronchi smooth muscle → bronchoconstrict

blood vessel walls → vasodilate

bronchi glands → secrete fluid and mucus

effect of SNS input on lungs

bronchi smooth muscle → bronchodilation

pulmonary glands → secretion

pulmonary vasculature → vasoconstrict

pulmonary thromboembolism definition + clinical significance

an obstruction blocking a pulmonary artery; potential rapid death

one of the most common pulmonary diseases + pathology

asthma

small airways are narrowed by inflammation and bronchoconstriction