The rectus abdominis at the level of xyphoid was supplied by a branch came from inferoir thorax artery, which diverged epigastric vessels at the same time.
For example, the brain is protected by the cranial bones, the spinal cord by the vertebrae, the heart and lungs by the rib cage, and internal reproductive organs by the pelvic bones.
Thoracic outlet syndrome is a group of symptoms caused by compression of the brachial plexus and the subclavian artery and vein as they travel through the narrow space between the collarbone and first rib, called the thoracic outlet.
These symptoms also occur in thoracic outlet syndrome where the same nerves as well as the subclavian artery and vein are compressed as they travel through the narrow space between the first rib and the clavicle.
Most mammals and reptiles rely on a flexible rib cage that expands to allow them to breathe, but turtles use abdominal muscles attached to the shell instead: one to breathe in, and one to breathe out.