424 



INTERNAL ILIAC ARTERY. 



into an external and an internal branch, which are deeply placed behind the 

 external obturator muscle. 



BRANCHES. (a) Within the pelvis, besides others of smaller size, the obturator 

 artery often supplies a branch to the iliac fossa and muscle, and one which run.s 

 backwards upon the urinary bladder. 



(b) Anastomotic vessels, which may be called pubic, are given off by the obturator 

 artery as it is about to escape from the pelvis : these vessels ramify on the back of the 

 pubes, and communicate behind the bone and the attachments of the abdominal 

 muscles, with small offsets from the epigastric artery. These anastomosing branches 

 lie to the inner side of the crural ring. 



(c) The internal terminal branch curves inwards beneath the obturator externus, 

 close to the inner margin of the thyroid foramen, and furnishes branches to the obtu- 

 rator muscles, the gracilis, and the adductor muscles. 



(d) The external terminal branch has a similar arrangement near the outer margin 

 of the thyroid foramen ; it descends as far as the ischial tuberosity, and supplies the 

 obturator muscles, and the upper ends of the long muscles which are attached to that 

 tuberosity. This branch usually sends off a small artery, which enters the hip-joint 

 through the cotyloid notch, and ramifies in the synovial fatty tissue, and along the 

 round ligament as far as the head of the femur. 



Fig. 291. 



Fig. 291. A. and B. VIEWS 

 OF THE LEFT WALL OF THM 

 PELVIS, WITH THE ATTACHED 

 ABDOMINAL MUSCLES FROM 

 THE INSIDE, SHOWING DIF- 

 FERENT POSITIONS OF THE 

 ABERRANT OBTURATOR AR- 

 TERIES (from R. Quaiti). 



In A, a case is represented 

 in which the aberrant artery 

 passes to the outside of a 

 femoral hernial protrusion ; in 

 B, an instance is shown in 

 which it surrounds the neck of 

 the sac. 



a, posterior surface of the 

 rectus muscle ; b, iliacus in- 

 ternus muscle ; c, symphysis 

 pubis ; d, obturator mem- 

 brane ; e, placed on the fascia 

 transversalis, points to the vas 

 deferens passing through the 

 internal inguinal aperture ; f, 

 the testicle ; + , the neck of a 

 femoral hernial sac ; 1, the 

 external iliac artery ; 2, the 

 external iliac vein ; below 2, 

 the obturator nerve; 3, the 

 epigastric artery; 4, aberrant 

 obturator artery, arising from 

 the epigastric. 



The two terminal branches 

 of the obturator artery com- 

 municate with each other near 

 the lower margin of the ob- 

 turator ligament, and anastomose with branches of the internal circumflex artery. 

 The external branch also communicates with offsets from the sciatic artery near the 

 tuber ischii. 



PECULIARITIES. The obturator artery frequently has its origin transferred to the 



