THE HYPOGASTRIC ARTERY 



621 



The Cutaneous Branches are distributed to the skin of the buttock and back of 

 the thigh. 



The iliolumbar artery (a. iliolumbalis) a branch of the posterior trunk of the 

 hypogastric, turns upward behind the obturator nerve and the external iliac vessels, 

 to the medial border of the Psoas major, behind which it divides into a lumbar and 

 an iliac branch. 



The Lumbar Branch (ramus lumbalis) supplies the Psoas major and Quadratus 

 lumborum, anastomoses with the last lumbar artery, and sends a small spinal 

 branch through the intervertebral 

 foramen between the last lumbar 

 vertebra and the sacrum, into the 

 vertebral canal, to supply the 

 cauda equina. 



The Iliac Branch (ramus iliacus) 

 descends to supply the Iliacus; 

 some offsets, running between the 

 muscle and the bone, anastomose 

 with the iliac branches of the ob- 

 turator; one of these enters an 

 oblique canal to supply the bone, 

 while others run along the crest of 

 the ilium, distributing branches to 

 the gluteal and abdominal muscles, 

 and anastomosing in their course 

 with the superior gluteal, iliac 

 circumflex, and lateral femoral 

 circumflex arteries. 



The lateral sacral arteries (aa. 

 sacrales laterales) (Fig. 539) arise 

 from the posterior division of the 

 hypogastric; there are usually two, 

 a superior and an inferior. 



The superior, of large size, passes 

 medialward, and, after anastomos- 

 ing with branches from the middle 

 sacral, enters the first or second 

 anterior sacral foramen, supplies 

 branches to the contents of the 

 sacral canal, and, escaping by the 

 corresponding posterior sacral fora- 

 men, is distributed to the skin and 

 muscles on the dorsum of the 



Termination oj 



medial femoral 



circumflex 



First 



perforating 



Second 



perforating 



__ Third 



perforating 



Termination 

 of profunda 



Superior muscular 



Lateral 



superior 

 genicular 



sacrum, anastomosing with the 

 superior gluteal. 



The inferior runs obliquely across 

 the front of the Piriformis and the 

 sacral nerves to the medial side of 

 the anterior sacral foramina, de- 

 scends on the front of the sacrum, 

 and anastomoses over the coccyx 

 with the middle sacral and opposite 

 lateral sacral artery. In its course it gives off branches, which enter the anterior 

 sacral foramina; these, after supplying the contents of the sacral canal, escapes 

 by the posterior sacral foramina, and are distributed to the muscles and skin on 

 the dorsal surface of the sacrum, anastomosing with the gluteal arteries. 



Medial superior genicular 



Sural 



FIG. 544. The arteries of the gluteal and posterior 

 femoral regions. 



