Thoracic Wall 1 Flashcards
What organs are protected by the thorax?
Heart + great vessels, lungs and major airways Liver Stomach Spleen Kidneys
How does the thorax assist resp?
Resists negative intra thoracic pressure
Works in partnership w the diaphragm + abdo muscles
Does haematopoiesis occur in the thorax?
ye
How many ribs are there in the thoracic cage?
12 pairs
What makes up the thoracic wall?
✓Thoracic cage
✓ Skin
✓Subcutaneous tissue ✓Thoracic muscles + fascia
✓3 layers of muscles extending between ribs [i.e. intercostal space]
✓Mammary gland/breast tissue
How to identify thoracic vertebra?
Inferior and superior articular processes are vertical and articular facets face slightly medially that allow some rotation but no flexion
Also they kinda look like a giraffe in lateral view
(Lumbar is moose, cervical is Sid the sloth)
What is the latin term for ribs and why isn’t helpful to know?
L. costae, cause things that are rib related are referred to as costal; re: costal cartilage
What are true ribs?
Attach to sternum directly through costal cartilage
What are false ribs?
Attach to sternum indirectly through costal cartilage of 7th rib (SEVENTH RIB)
What are the floating ribs?
Floating ribs (11-12) do not articulate with sternum
What ribs are true ribs?
pairs 1-7
What ribs are false ribs?
pairs 8-10
What ribs are floating ribs?
pairs 11-12
What are the different rib categories by sternal articulation and what ribs fall into these categorisations?
✓ True ribs (1-7) attach sternum directly through costal cartilage
✓ False ribs (8-10) attach sternum indirectly through costal cartilage of 7th rib
✓ Floating ribs (11-12) do not articulate with sternum
What ribs are ‘typical ribs’ in terms of structure?
Ribs #2(3)-9(10)
What structures are found on a typical rib?
Head, Neck, Tubercle, Body (shaft) + Costal angle
Where is the costal groove on a typical rib?
Costal groove on the inner surface and close to the inferior border for the intercostal nerves and vessels
What is different about the first rib?
✓Scalene tubercle attachment for anterior scalene muscle
✓Groove for subclavian vein
✓Groove for subclavian artery
and the inferior trunk (C8 and T1) of the brachial plexus
✓Single facet on head to articulate with T1 vertebra only
✓No costal groove
What are atypical about the floating ribs?
• Are not attached to the sternum
• Heads articulate only with corresponding vertebra
• Do not articulate with the transverse processes
Rib #12 is related to pleura (watch out in kidney surgery)
What structures make up the sternum?
Manubrium, body and xiphoid process (xiphisternum)
what is the sternal angle?
The point of the manubriums articulation with the body of the sternum
What is found at the level of the sternal angle?
− 2nd Costal Cartilage (CC)
− Intervertebral disc between T4 and T5 vertebra
− The proximal and distal boundaries of the aortic arch
− The bifurcation of the trachea
− Superior limit of the pulmonary trunk
− Azygos vein opening to SVC
− Ligamentum arteriosum