Abdomen, Diaphragm, Pelvic Cavity Flashcards
Trunk Cavities
thoracic, abdominal, pelvic
Thoracic Cavity
- upper border = superior thoracic aperture
- lower border = inferior thoracic aperture
- floor = diaphragm
Rib Classification
- true (1-7) = attach to sternum independently
- flase (8-10) = join together to attach to sternum
- floating (11-12) = do not attach to sternum
Scapular Levels
- superior angle = T2
- root of spine = T3
- inferior angle = T7
Costovertebral (CV) Joint
- b/w rib and vertebral body
- upper head of rib articulates w/ superior vertebra
- lower head of rib articulates w/ inferior vertebra
Sternocostal Joint
- b/w sternum and costal cartilages
- upper 7
- 1st = fibrocartilaginous
- 2-7 = synovial
Thoracic Vertebrae
- heart shaped vertebral body
- smaller vertebral foramen
- nearly vertical articular facets
- long, sloped downward SP
- demifacets for articulation w/ head of ribs
Rule of 3’s for Thoracic Vertebrae
- T1-T3 = SP and TP are in the same plane as the vertebral body
- T4-T6 = SP hand over intervertebral space below, TP is 1/2” superolateral
- T7-T9 = SP over body of vertebra below, TP is 1” superolateral
- T10-T12 = SP and TP are in the same plane as the vertebral body
Serratus Posterior Superior/Inferior
assist with elevation/depression of ribs during forced breathing
Thoracic Arterial Supply
- mostly segmental … arteries come off thoracic aorta at each vertebral level
- internal thoracic arteries come off subclavian artery
- intercostal artery and nerve travel in subcostal groove
Trunk Dermatomes
- segmental
- T2 = axilla
- T4 = nipple
- T6 = xiphoid process
- T10 = umbilicus
Diaphragm
- main muscle of inspiration
- double dome (right and left)
- inserts and originates onto itself via central tendon
- 3 openings
- connections to arcuate ligaments, crural fibers, psoas muscle, quadratus lumborum
Structures Passing Through Diaphragm
- T8 = inferior vena cava (IVC)
- T10 = esophagus, vagus nerve
- T12 = aorta, thoracic duct
*R to L = IVC > esophagus > aorta
Abdominal Aorta
splits at L4 into left and right common iliac artery
Phrenic Nerve
- nerve roots from cervical 3-5
- right and left side each innervate its dome of the diaphragm
Other Effects of Diaphragmatic Motion
- enhances venous return from LE (diaphragmatic pump)
- controls intra-abdominal pressures (spinal stabilization, coughing, valsalva maneuver, child birth)
- parasympathetic relaxation (stress control, meditation, pelvic floor training)
Pelvic Floor Functions
breathing, spine, bowel, bladder, sexual, floor of pelvis
Hip Flexors
psoas major + iliacus
- join together distally to form a common tendon (iliopsoas)
Posterior Abdominal Wall Muscles
psoas major + minor, iliacus, quadratus lumborum
Abdominal Muscles
rectus abdominis, external oblique, internal oblique, transversus abdominis
Fiber Directions of Abdominal Muscles
- RA = vertical
- EO = down and in
- IO = down and out
- TA = horizontal
