Thorax Flashcards
Anterior median (midsternal) line
vertical line through sternum in mid-saggital plane
Midclavicular Lines (MCLs)
vertical through mid points of the clavicles, parallel to median line
Anterior Axillary line
vertical line along anterior axillary fold (pec major)
Mid Axillary line
vertical line through apex of axilla
Posterior axillary line
vertical line through posterior fold (formed by latissimus dorsi and teres major)
Posterior median (mid spinal or midvertebral) line
vertical line through spinous processes of vertebrae in mid-saggital plane
Scapular Lines
vertical lines that pass through inferior angles of scapula, line is parallel to posterior median line
Thoracic Wall
Bones: ribs, thoracic vertebrae, sternum
Function: protect thorax (heart, lungs, blood vessels, esophagus)
True Ribs
1-7
attach directly to sternum`
False Ribs
8-10
attach indirectly to sternum
Floating Ribs
11-12
do not attach to sternum
Typical & Atypical
Typical- 3-9 have 2 facets
atypical-1,2 10-12 (1-2 have areas for scalenes to attach, have 2 facets and articulate with 2 vertebral bodies)
Thoracic Vertebrae
costal facets on vertebral body and transverse process, ribs articulate with them
Sternum
made up of manubrium, body and xyphoid process
Manubrium
jugular notch
articulates with clavicle & 1st rib
Body of sternum
forms sternal angle w/manubrium
is where trachea bifurcates (carnia), beginning & end of aortic arch, palpation of sternal angle is location of 2nd rib
Xiphoid Process
site of subcostal angle
Joints of the Thorax
costovertebral joint costochondrial joint sternocostal sternoclavicular joint manubriosternal joint xiphosternal
Male Breast
nipple lies at approx. 4th intercostal (between ribs 4 and 5)
Female Breast
ribs 2-6
glandular, approx 15-20 lobes drain into ducts
approx 75% of breast drains lateral into axillary lymph nodes
Superior Aperture
CONTAINS:
esophagus
trachea
nerves & blood vessels that supply head, neck & ue
Inferior Aperture
Allows, IVC, and aorta to pass inferiorly
Transversus Thoracis
expiration, located along internal ribs, located on internal anterior thoracic cage
O-Posterior surface of lower sternum
I-internal surface of costal cartilage 2-6
N-Intercostal nerve
A-expiration
Subcostal Muscles
inspiration, located on internal portion of ribs
located in interior posterior thoracic cage
O-internal surface of lower ribs near angles
I- superior boarders of 2nd or 3rd ribs
N- intercostal nerve
A-Inspiration
Diaphragum
innervated by phrenic nerve
major muscle for inspiration
contraction flattens diaphragum, increases thoracic volume, change in pressure causes increase of air into the lungs
Intercostal Space
3 layers- external, internal and innermost intercostal muscle
contains intercostal vein, artery and nerve
Descending Aorta
provides blood to segmental branches known as posterior intercostals arteries
Posterior Intercostals Arteries
come off descending aorta travel anteriorly between ribs (along intercostal vein and intercostal nerves)
Subclavian Arteries
provide blood to R/L internal thoracic arteries
internal thoracic artery
anterior intercostals arteries
Internal Thoracic Artery
descends along anterior wall of internal rib cage
Anterior Intercostals Arteries
originates from descending internal thoracic artery
travels between ribs and anastomose with posterior intercostals arteries
Azygos Vein
right posterior internal rib cage, drains into SVC
drains throax
Hemiazygos & Accessory Hemiazygos Vein
left posterior internal rib cage
hemiazygos drains segmental portions of thorax
Visceral Pleura
lines the lungs themselves
Parietal Pleura
lines thoracic cavity wall and diaphragm
Costodiaphragmatic Recesses
pleural recess that can accumulate fluid with various conditions, lateral and posterior
Levator Costarum
Posterior, external thoracic rib cage O- Transverse process of T7-T11 I- Subjacent ribs between tubericle & angle N- posterior primary rami A- Elevates ribs, inspiration
Costomediastinal Recesses
small, pleural recess located posterior to sternum
where pneumothroax, pleural effusion, hemothroax and pleuritis would occur
