Veterinary Gross Anatomy-II

EXTERNAL ILIAC ARTERY

• The hind limb is supplied with blood by the external iliac artery.
• Each arises from lateral surface of aorta just in front of the internal iliac artery.
• It passes downward and backward along the tendon of psoas parvus to the side of the pelvic inlet crosses the tendon reaches the anterior border of the pubis, gains the space between sartorius and pectineus and is continued as the femoral artery.
• In its course, it is covered by peritoneum and is related laterally to the tendon of psoas minor, sartorius and iliacus and medially to the common iliac vein, posteriorly to the external iliac vein. (View the Vascular pattern in pelvic cavity)

Collateral Branches

Circumflex iliac artery

• It is a large vessel arising from the external iliac artery close to its origin passes downwards, towards the lateral angle of the ilium supplying branches to psoas major and iliacus and divides into superior and inferior branches.
• The anterior (superior) branch runs downwards and forwards on the transverse abdominis then gets under the internal oblique muscle perforates it gets under the external oblique muscle and finally reaches the skin of the flank. It supplies all these muscles and skin.
• The posterior (inferior) branch also supplies branches to the iliopsoas, penetrates the abdominal wall descends on the deep face of the tensor fascia late and supplies to these muscles, the prefemoral lymph gland and skin of the thigh.
• A common trunk arises from the anterior face of the external iliac artery and this divides into two branches the prepubic and deep femoral arteries.

Prepubic artery

• Prepubic artery passes forwards from its origin crosses the Poupart’s ligament and divides into external pudic and posterior abdominal arteries.
  • The external pudic artery branch supplies chiefly the scrotum in the male. It descends on the Poupart’s ligament in the inguinal canal at the posterior border of the spermatic cord passes out of the canal at the external inguinal ring and gives off the subcutaneous abdominal artery and branches to scrotum. The subcutaneous abdominal artery passes forwards on the tunica abdominalis supplies branches to the scrotum, superficial inguinal lymph gland and skin. In the female this vessel is very large and termed the mammary artery, which passes through the inguinal canal and divides into two branches an anterior and a posterior to supply the mammary gland. A small subcutaneous abdominal artery arising from the anterior mammary artery supplies the skin in front of the mammary gland.
  • The posterior abdominal artery crosses the spermatic cord supplies branches to the internal oblique muscle runs forwards on the deep face of the rectus abdominis and is distributed to it. Its branches anastomose with those of the anterior abdominal artery. The artery of spermatic cord or cremasteric artery or external spermatic artery is a very small vessel that arises usually from the posterior abdominal artery, passes through the inguinal canal along the posterior border of the cremaster externus, and supplies branches to this muscle, tunica vaginalis and the other structures of the cord. In the female, this branch is represented by a small vessel, which supplies the anterior part of the uterus.

Deep femoral artery

• Deep femoral atery is a large vessel usually arising by a common trunk with the prepubic artery.
• It passes under Poupart’s ligament between the iliacus and pectineus muscles.
• Then it divides into two sets of vessels, which supply the biceps femoris and semitendinosus.
• Its supplies in its course branches to pectineus, gracilis obturator externus, adductor semimembranosus, quadratus femoris, biceps femoris, semitendinosus hip joint and obturator internus.