Trunk vessels (aorta, vena cava, abdominal branches)
Abdominal aorta
Aorta abdominalis (Pars abdominalis aortae)
- Origin
- Begins at the aortic hiatus of the diaphragm (T12 level) as the continuation of the thoracic aorta
- Insertion
- Descends retroperitoneally anterior to L1-L4 vertebrae to bifurcate at L4 into the left and right common iliac arteries
- Function
- Primary arterial trunk supplying all abdominal viscera, pelvic organs, and the lower limbs via unpaired visceral branches (celiac, SMA, IMA), paired visceral branches (renals, gonodals), and parietal branches (phrenic, lumbars)
- Innervation
- Abdominal aortic plexus
- Movement & chain
- Transmits strong systolic expansile pulsations
- Palpation
- Palpable in thin individuals as an expansile midline pulsation superior to the umbilicus
- Clinical
- Abdominal aortic aneurysm (AAA, infrarenal diameter >3.0 cm; rupture carries high mortality with the classic triad of sudden back/abdominal pain, pulsatile abdominal mass, and shock), Leriche syndrome (aortoiliac occlusive disease: buttock claudication, erectile dysfunction, absent femoral pulses).
- Segmental innervation
- T12-L4 spinal segments
- In clinical practice
- Ultrasound screening for AAA, perioperative care for EVAR and open surgical repair, groin puncture site hematoma checks, peripheral pulse monitoring (dorsalis pedis, posterior tibial)
- Region in the model
- Trunk vessels (aorta, vena cava, abdominal branches)