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EXTERNAL ILIAC ARTERY. 



The external iliac artery of each side passes obliquely downwards 

 along the inner border of the psoas muscle, from opposite the sacro- 

 iliac symphysis to the femoral arch, where it becomes the femoral 

 artery. 



Relations. It is in relation in front with the spermatic vessels, the 

 peritoneum, and a thin layer of fascia, derived from the iliac fascia, 

 which surrounds the artery and vein. At its commencement it is 

 crossed by the ureter, and near its termination by the crural branch 

 of the genito-crural nerve and the circumflexa ilii vein. Externally it 

 lies against the psoas muscle, from which it is separated by the iliac 

 fascia; and posteriorly it is in relation with the external iliac vein, which, 

 at the femoral arch, becomes placed to its inner side. The artery is 

 surrounded throughout the whole of its course by lymphatic vessels 

 and glands. 



Branches. Besides several small branches which supply the glands 

 surrounding the artery, the external iliac gives off two branches, the- 

 Epigastric, 

 Circumflexa ilii. 



The Epigastric artery arises from the external iliac near Poupart's 

 ligament; and passing forwards between the peritoneum and transver- 

 salis fascia, ascends obliquely to the border of the sheath of the rectus. 

 It enters the sheath near its lower third, passes upwards behind the 

 rectus muscle, to which it is distributed, and in the substance of that 

 muscle inosculates near the ensiform cartilage with the termination 

 of the internal mammary artery. It lies internally to the internal 

 abdominal ring and immediately above the femoral ring, and is crossed 

 near its origin by the vas deferens in the male, and by the round liga- 

 ment in the female. 



The only branches of the epigastric artery worthy of distinct notice 

 are the Cremasteric, which accompanies the spermatic cord and sup- 

 plies the cremaster muscle ; and the ramusculus which inosculates 

 with the obturator artery. 



The Epigastric artery forms a prominence of the peritoneum which 

 divides the iliac fossa into an internal and an external portion ; it is 

 from the former that direct inguinal hernia issues, and from the latter, 

 oblique inguinal hernia. 



The Circumflexa ilii arises from the outer side of the external iliac, 

 nearly opposite the epigastric artery. It ascends obliquely along 

 Poupart's ligament, and curving around the crest of the ilium between 

 the attachments of the internal oblique and transversalis muscle, inos- 

 culates with the ilio-lumbar and inferior lumbar artery. Opposite 

 the anterior superior spinous process of the ilium, it gives off a large 

 ascending branch which passes upwards between the internal oblique 

 and transversalis, and divides into numerous branches which supply 



