Exam 2: Thoracic Wall Flashcards
3 parts of sternum
- Manubrium
- Body
- Xiphoid process
Widest and thickest part of sternum
Manubrium
Body of sternum articulates with
2nd—7th costal cartilages
What part of the sternum is broken sometimes broken during CPR
Xiphoid process
Articulation of manubrium w/ body of sternum forms
Sternal angle
Sternal angle found at what level
T4/T5 IVD
Superior thoracic aperture AKA
Thoracic inlet
Superior thoracic aperture bounded by
Manubrium
1st rib
1st thoracic vertebra
Inferior thoracic aperture AKA
Thoracic outlet
Inferior thoracic aperture bounded by
- Xiphoid process
- Costal margin
- 12th rib
- Distal end 11th rib
- 12th thoracic vertebra
2 types of ribs
True ribs and false ribs
True ribs
Ribs 1-7
Articulate with sternum directly
False ribs 8-10
Articulate with sternum indirectly, attach to costal cartilage of rib above
False ribs 11 and 12
Not connected to sternum at all
“Floating ribs”
Typical ribs
3-9
Atypical ribs
1, 2, 10, 11, 12
Morphology of typical ribs
Head, neck, tubercle, angle, shaft, costal groove
Functions of thoracic cage
- Protection
- Muscle attachments
- Respiration
External intercostal muscle runs from ____ to _____.
Lower border (ribs 1-11) to upper border (ribs 2-12)
External intercostal muscle function
Elevates ribs in inspiration
Internal and innermost intercostal muscles runs from _____ to _____
Upper border (ribs 2-12) to lower border (ribs 1-11)
Muscles of thoracic wall that function to depress ribs in forced expiration
Internal intercostal
Innermost intercostal
Subcostalis
Transversus thoracic
External intercostal muscles begin at _____ and end at ____
Tubercle of rib; costochondral joint
External intercostal muscles replaced by
External intercostal membrane
Internal intercostal muscles begin at ____ and end at ____
Sternum; angle of ribs
Internal intercostal muscles replaced by
Internal intercostal membrane
Functions of muscles of thoracic wall EXCEPT external intercostal muscle
Depress ribs in FORCED expiration
External intercostal muscle fibers run
Downward and forward
Internal and innermost intercostal muscle fibers run
Downward and backward
Anterior aspect of thoracic wall supplied by
Internal thoracic artery and its branches
Internal thoracic artery branches
Pericardiacophrenic
Anterior intercostal
Musculophrenic
Superior epigastric
Lateral terminal branch of internal thoracic artery
Musculophrenic artery
Medial terminal branch of internal thoracic artery
Superior epigastric artery
Pericardiacophrenic artery supplies
Pleura
Pericardium
Diaphragm
Anterior intercostal artery supplies
Upper 6 intercostal spaces
Creates anastomose
Posterior aspect of thoracic wall supplied by
Supreme intercostal artery
Posterior intercostal arteries
Subcostal artery
Anterior aspect of thoracic wall drained by
Internal thoracic vein
Internal thoracic vein is _____ to arteries
Medial
On the R side the 1st posterior intercostal drains into
Brachiocephalic vein
On the R side, the 2nd and 3rd posterior intercostal veins joint to form ________ which drains into _______
Superior intercostal vein; azygos vein
On the R side, the 4th-11th posterior intercostal and subcostal veins drain into
Azygos vein
On the L side, the 1st posterior intercostal veins drains into
Brachiocephalic vein
On the L side, 2nd and 3rd posterior intercostal veins join to form _____ which drains into ______
Superior intercostal vein; LEFT brachiocephalic vein
On the L side, 4th thru 8th posterior intercostal veins join to form _____ which drains into _____
Accessory Hemiazygos vein; azygos vein
On the L side, 9th thru 11th posterior intercostal and subcostal veins join to form ______ which drains into _____
Hemiazygos vein; azygos vein
Nerves of thoracic wall
Intercostal nerves (1-11) Subcostal nerve (12)
Endothoracic fascia function
Prevents innermost intercostals from rubbing against parietal pleura
Thickening of endothoracic fascia
Suprapleural membrane
Intercostal V.A.N lie within _____ between _____.
Costal groove; internal and innermost intercostal muscles
3 cavities that make up thoracic cavity
2 pleural cavities
1 mediastinum
Pleural cavities surround
Lungs
Parietal pleura
Lines inner surface of thorax
Visceral pleura
Invests the lung
Pleural cavity is a
Potential space
Pleural fluid
Lubricates pleurae to minimize friction
4 parts of parietal pleura
Costal
Mediastinal
Diaphragmatic
Cervical
Costodiaphragmatic recess location
Where costal and disphragmatic pleurae meet
Midaxillary line
Costomediastinal recess location
Costal and medistinal pleurae meet
Blood supply to parietal pleura
Intercostal, internal thoracic and superior phrenic arteries
Visceral pleura supplied by
Bronchial artery
Parietal pleura innervation
Intercostal, subcostal and phrenic nerves
Parietal pleura is
HIGHLY sensitive to pain
Visceral pleura innervation
None
Insensitive to pain
Pneumothorax
Pleural cavities fill with air
Causes of pneumothorax
Trauma
Disease
Congenital weak spot
Tension pneumothorax
Flap present on visceral pleura
Air enters but cannot exit
Hemothorax
Pleural cavity fills with blood
Hemopneumothorax
Pleural cavity fills with air and blood
Pleuritis produces
Pleural friction rub