Blood Vessels of Trunk

Branches of thoracic aorta

Posterior intercostal arteries, run into intercostal spaces, supply structures of intercostal spaces

Branches of abdominal aorta

Once aorta has passed behind diaphragm, name changes to abdominal aorta, lumbar arteries supply structures of posterior abdominal wall

Spinal arteries supplying column and cord

One anterior - supplies 2/3 of spinal cord and adjacent vertebral column structures, two posterior - supplies 1/3 of spinal cord and adjacent vertebral column structures

Spinal arteries anatomy

Run length of spinal cord, only large enough to provide adequate supply to upper cervical spinal cord and adjacent vertebral column structures

Booster arteries

Spinal branches of vertebral, posterior intercostal and lumbar arteries, provide adequate blood supply to lower cervical, thoracic, lumbar and sacral spinal cord and vertebral column, enter vertebral column through intervertebral canals and join spinal arteries

Internal vertebral venous plexus 

Drains into intervertebral veins which pass through intervertebral canal, direction of blood flow varies in response to changes in intra thoracic and intra abdominal pressure

Intervertebral veins

Drain into vertebral, posterior intercostal and lumbar veins and from there into inferior or superior vena cava

Blood supply of column

Posterior intercostal veins drain into azygous system

Azygous system rhs

Posterior intercostal veins drain directly into azygous system

Azygous system lhs

Posterior intercostal veins drain into left brachiocephalic trunk, accessory hemiazygous vein and hemiazygous vein

Azgyous vein

Drains into superior vena cava