External iliac vein

Examples of External iliac vein in the following topics:

• Veins of the Abdomen and Pelvis

  • The external iliac vein, the upward continuation of the femoral vein, passes upward along the pelvis and ends to form the common iliac vein.The tributaries of the external iliac vein are the inferior epigastric, deep iliac circumflex, and pubic veins.
  • The internal iliac vein begins near the upper part of the greater sciatic foramen, the large opening at the rear of the pelvis, passes upward behind and slightly medial to the internal iliac artery and, at the brim of the pelvis, joins with the external iliac vein to form the common iliac vein.
  • The inferior epigastric vein refers to the vein that drains into the external iliac vein and arises from the superior epigastric vein.
  • The deep circumflex iliac vein is formed by the union of the venae comitantes of the deep iliac circumflex artery, and joins the external iliac vein about 2 cm above the inguinal ligament.
  • The veins of the abdomen and lower limb include the inferior vena cava, the common iliac veins, the external iliac veins, and their tributaries.

• Veins of the Lower Limbs

  • The posterior and anterior tibial veins return blood from the calf, ankle, and foot and merge into the popliteal vein behind the knee.
  • The popliteal vein then carries blood from the knee joint up through the thigh.
  • The femoral vein merges with the great saphenous vein in the groin to form the external iliac vein.
  • Running the full length of the leg, making it the longest vein in the body, the great saphenous vein is a superficial vein that returns blood from the foot and superficial muscles of the leg before merging with the femoral vein to form the external iliac vein.
  • Outline the flow of blood in the veins of the lower limbs

• Principal Veins

  • Deep veins are often of larger caliber than superficial veins and carry the majority of the blood within the circulatory system.
  • Communicating veins, or perforator veins if they pass through a large muscle mass, directly connect superficial and direct veins.
  • The venae cavae are the veins with the largest diameter.
  • The inferior vena cava is formed from the common iliac veins that serve the legs and abdomen.
  • There are four pulmonary veins, two from each lung, each of which forms from three to four bronchial veins.

• Great Vessels of the Heart

  • The right and left subclavian veins, jugular veins, and thyroid veins feed into the superior vena cava.
  • The left and right common iliac veins converge to form the inferior vena cava at its lowest point.
  • Along the way up the body from the iliac veins, the renal and suprarenal veins (kidney and adrenal glands), lumbar veins (from the back), and hepatic veins (from the liver) all drain into the inferior vena cava.
  • The aorta extends around the heart and travels downward, diverging into the iliac arteries.
  • The descending aorta is  the section from the arch of aorta to the point where it divides into the common iliac arteries.

• Lymphatic Tissue Development

  • Lymphatic vessels develop from lymph sacs that arise from developing veins, which are derived from mesoderm.
  • It develops from the primitive vena cava and mesonephric veins.
  • The sac establishes connections with the cisterna chyli, but loses connections with neighboring veins.
  • The last of the lymph sacs, the paired posterior lymph sacs, develop from the iliac veins.
  • The posterior lymph sacs join the cisterna chyli and lose their connections with adjacent veins.

• Abdominal Aorta

  • Posteriorly, it is separated from the lumbar vertebrae by the anterior longitudinal ligament and left lumbar veins.
  • Terminally it branches into the paired common iliac arteries, which supply the pelvis and lower limbs.
  • The aorta, highlighted in red, includes the abdominal aorta which begins at the diaphragm and ends as it branches into the common iliac arteries.

• Development of the Heart

  • While the arterial system develops mainly from the aortic arches, the venous system arises from three bilateral veins during weeks four through eight of human development.
  • After birth, the umbilical arteries form the internal iliac arteries.
  • The human venous system develops mainly from the vitelline veins, the umbilical veins, and the cardinal veins, all of which empty into the sinus venosus.

• Physiological Changes

  • Edema (swelling) of the feet is common during pregnancy, partly because the enlarging uterus compresses veins and lymphatic drainage from the legs.
  • Clots usually develop in the left leg or the left iliac venous system because the left iliac vein is crossed by the right iliac artery.
  • The increased flow in the right iliac artery after birth compresses the left iliac vein leading to an increased risk for thrombosis (clotting) that is exacerbated by a lack of ambulation (walking) following delivery.

• Anastomoses

  • Circulatory anastomoses are named based on the vessels they join: two arteries (arterio-arterial anastomosis), two veins (veno-venous anastomosis), or between an artery and a vein (arterio-venous anastomosis).
  • Anastomoses between arteries and anastomoses between veins result in a multitude of arteries and veins serving the same volume of tissue.
  • Examples include the knee and geniculate arteries, shoulder and circumflex humeral, and hip and circumflex iliac.

• Fetal Circulation

  • Oxygen then diffuses from the placenta to the chorionic villus, an alveolus-like structure, from which it is carried to the umbilical vein.
  • Blood from the placenta is carried to the fetus by the umbilical vein.
  • The branch of the umbilical vein that supplies the right lobe of the liver first joins with the portal vein.
  • Some of the blood moves from the aorta through the internal iliac arteries to the umbilical arteries and re-enters the placenta, where carbon dioxide and other waste products from the fetus enter the maternal circulation.