Thoracic Wall Flashcards
Intercostal Spaces
Intercostal spaces, muscles, neurovascular supply
Bones of Wall
Thoracic vertebrae, ribs, sternum
Palpable structures of anterior wall
Suprasternal notch, manubrium, sternal angle, body of sternum, costal cartilage, xiphoid processes
Which ribs aren’t palpable?
Ribs 1, 11, 12
Sternal angle anatomical events
Rib 2 articulates w/ sternum
Intervertebral disc T4-T5
Costal margin
Made from costal cartilages 7-10
Site of nipple
Intercostal space 4 @ middle clavicular plane
True ribs
1-7, cartilage attaches to sternum
False ribs
Ribs 8-10. Attaches to cartilage of 7
Contents of intercostal space
- 3 layers of muscle (external, internal, innermost)
2. Neurovascular supply (btwn internal and innermost)
External Intercostal muscles
Fibers directed inferiorly & medially (anterior thorax)
Internal intercostal muscles
Fibers inferiorly & laterally (ant thorax)
Innermost muscles group
Discontinuous group of 3 muscles directed inferiorly and laterally (ant thorax)
External costal membrane
Replaces muscle near sternum or costal margin
Internal intercostal membrane
Replaces muscle at vertebral column
3 subgroups of Innermost muscle group
- Innermost
- Subcostalis
- Transversus thoracis
Innermost muscle
Lateral thoracic wall, stay w/in 1 space
Subcostalis
Near vertebrae, spans 1-2 spaces
Transversus thoracis
Near sternum, span 1-2 spaces, DEEP to internal thoracic vessels
Intercostal neurovascular bundle
- Btwn internal & innermost muscles
- @inferior border of rib (costal groove)
- V,A,N
Pleural tap (thoracentesis)
Inserted in midaxillary space in middle of 4th intercostal space
-removing fluid from pleural cavity
Posterior intercostal arteries
Branch of aorta
Supply muscles, fascia, skin
Anterior intercostal artery
Branch of internal thoracic artery
Supply muscles, fascia, skin
intercostal artery anastomoses
Ant. And post. anastomose at intercostal space