The ovarian arteries arise from the aorta just below the renal arteries. They pass distaily under the peritoneum, resting on the psoas major muscle. On entering the pelvis, the arteries are enclosed in the layers of the suspensory ligament of the ovary.
SUPERIOR RECTAL ARTERY
The superior rectal artery is the continuation of the inferior mesenteric artery and descends between the layers of the mesentery of the sigmoid colon crossing the left common iliac artery. Opposite the distal portion of the sacrum the artery divides into two branches that descend on either side of the rectum.
MIDDLE SACRAL ARTERY
The middle sacral artery arises from the distal portion of the aorta posteriorly, descending behind the left common iliac vein and anterior to the fifth lumbar vertebra and the sacrum. The corresponding vein drains into the left common iliac vein.
COMMON ILIAC ARTERIES
The common iliac arteries descend obliquely from the fourth lumbar vertebra to the pelvic brim. The vessels bifurcate into the external and internal iliac arteries opposite die lumbosacral joint. There are accompanying common iliac veins that unite to form the inferior vena cava. These vessels are slightly posterior and a portion of the right common iliac vein is lateral to the right common iliac artery, whereas the left common iliac is always medial. Each common iliac vein receives the iliolumbar and sometimes the lateral sacral veins. As stated previously, the left common iliac vein receives the middle sacral vein as well.
EXTERNAL ILIAC ARTERY
The external iliac artery passes laterally along the medial border of the psoas major muscle to a midpoint beneath the inguinal ligament between the anterior superior iliac spine and the pubic symphysis. It enters the thigh and becomes the femoral artery.
INTERNAL ILIAC ARTERY
The internal iliac artery is the main arterial supply of the pelvis. It enters the pelvis behind the ureter and anterior to the internal iliac vein in the sacroiliac joint. The artery divides into anterior and posterior trunks at the upper border of the greater sciatic foramen. The anterior trunk has three somatic branches and four visceral branches.
(Fig. 1) Branches of the common iliac artery. The common iliac artery divides into an internal and an external branch. The internal iliac artery supplies the gluteal and internal pelvic structures, whereas the external iliac artery continues inferiorly as the femoral artery, the major blood supply to the entire lower limb.
(Fig. 2.) Pelvic blood supply.