43 6 APPLIED ANATOMY. 



the outer wall of the ischiorectal space. The rectovesical fascia passes downward 

 and inward over the levator ani muscle to cover the pyriformis and coccygeus 

 muscles behind, then the rectum, vagina, and bladder in front. In the male it 

 covers the prostate gland, forming its sheath, and at its anterior portion forms the 

 deep or posterior layer of the triangular ligament of the perineum. This pelvic 

 fascia acts as a barrier between the abdominal and pelvic cavities above and the 

 perineal region below. Pus originating above it tends to form an abscess which 

 rises toward the abdominal cavity, and pus originating below it tends to work toward 

 the surface in the perineum. 



Iliac Vessels. The iliac arteries commence at the bifurcation of the aorta on 

 the left side of the disk between the third and fourth lumbar vertebrae. This is 2 cm. 

 ( 24 in- ) below and to the left of the umbilicus and on a level with a line joining the 

 highest points of the iliac crests. They run in a line drawn from this point to mid- 

 way between the anterior superior spine of the ilium and the symphysis pubis. This 

 is to the inner side of the middle of Poupart's ligament. They are about 15 cm. 

 (6 in.) in length, the upper third, 5 cm. (2 in.), being the common iliac and the 

 lower two-thirds, 10 cm. (4 in.), being the external iliac arteries. The internal 



Aponeurosis of the external oblique 



Internal oblique and 

 transversalis muscles 



External iliac artery 

 External iliac vein 

 Deep epigastric artery 

 Deep epigastric vein 



FIG. 443. Ligation of the external iliac artery. 



iliac comes off opposite the sacro-iliac joint on or a little above a line joining the 

 anterior superior spines. The right common iliac artery is a little the longer because 

 it comes from the left side of the vertebral column, and the left common iliac vein is 

 the longer because it goes to the right side. The left iliac veins lie to the inner side 

 of the left iliac arteries in their entire course. The tight iliac vein starts at the 

 inner side of the right external iliac artery and then passes behind it to reach the 

 vena cava on the right side of the vertebral column. The ureters cross the iliac 

 arteries at their bifurcation, and in the female are accompanied by the ovarian arteries 

 and veins. The genitocrural nerve passes downward on the external iliac artery and 

 goes with it beneath Poupart's ligament. Lymphatic nodes accompany the iliac 

 vessels and drain the lower extremity, the abdomen below the umbilicus and the 

 pelvic viscera. 



Ligation of the Iliac Arteries. The iliac arteries can be reached for liga- 

 tion through an incision 2 cm. above and parallel to Poupart's ligament, reaching 

 from the inner side of the external iliac artery to above the anterior superior spine 

 if necessary. If the external iliac only is to be ligated this can be done through a 

 comparatively small incision, but if it is desired to reach the internal or common iliac 

 then the incision must be quite large. When the peritoneum is reached it is lifted 

 up from the iliac fascia beneath and the external iliac artery followed up as far as 

 desired. When the peritoneum is raised the ureter is usually lifted with it; it will 

 be encountered crossing. the point of bifurcation of the common iliac into the external 

 and internal iliacs. The relation of the veins to the iliac artery on the two sides is 

 to be borne in mind when passing the needle (Fig. 443) . 



