GL UTEA L— HYPOGASTRIC— VESICAL 569 



3. THE GLUTEAL ARTERY 



The gluteal artery, the largest Ijranch of the posterior division of the internal 

 iliac, e<jni(-s off as a short, thick trunk from the outer and back part of that vessel 

 of which indeed it may be regarded as the continuati(jn. Passing backwards 

 Ijetween the first sacral nerve and the lumbo-sacral cord through an osseo-tendinous 

 arch formed hy the margin of the bone and the upper edge of the pelvic fascia, it 

 leaves the pelvis through the great sacro-sciatic foramen above the pyriformis muscle 

 in company with its vein and the superior gluteal nerve. At its exit posteriorly 

 from the great sciatic foramen it lies under cover of the gluteus maximus and 

 beneath the gluteal vein, and in front of the superior gluteal nerve. It here breaks 

 up into two chief branches, a superficial and a deep. Its emergence from the 

 l»elvis is indicated on the surface l)y a point situated at the junction of the })Osterior 

 with the middle third of a line drawn from the anterior superior to the posterior 

 superior spine of the ilium. 



Branches of the gluteal artery: — 



(a) ^A^ithin the pelvis, branches are distributed to the obturator internus, the 

 pyriformis, the levator ani, the coccygeus, and the pelvic bones. 



(b) External to the pelvis, the artery divides into a superficial and deep 

 branch. 



(i) The superficial branch breaks up into a number of large vessels for the 

 supply of the upper i)orti<jn of the gluteus maximus, some of them piercing the 

 muscle and supplying the skin over it, and anastomosing Avith the posterior 

 branches of the lateral sacral arteries; whilst one of larger size, emerging from the 

 muscle near the iliac crest, anastomoses with the deep circumflex iliac artery. The 

 lower branches to tlie muscle anastomose with l^ranches of the sciatic. 



(ii) The deep branch subdivides into a superior and an inferior branch. («) The 

 superior skirts along the line of origin of the gluteus minimus, Ijetween the gluteus 

 medius and the l)one, and, emerging in front from l^eneath these muscles umhn* 

 cover of the tensor fasciae femoris (fig. 368), anastomoses with the ascending branch 

 of the external circumflex and deep circumflex iliac arteries, (fi) The inferior 

 branch passes forwards between tlie gluteus medius and minimus, accompanied by 

 the l)ranch to the tensor fascite femoris of the inferior division of the superior 

 gluteal nerve towards the great trochanter, where it anastomoses with the ascen<ling 

 branch of the external circumflex. It supplies branches to the contiguous muscles 

 and to the hip-joint. 



The deep branch before its division gives off the external nutrient artery of the 

 ilium. 



BiJAxrHES OF thp: Anterior Division of the Internal Iliac Artery 



1. THE HYPOGASTRIC ARTERY 



The hypogastric artery, the main trunk of the internal iliac in the foetus, is 

 the apparent continuation of the anterior Ijranch of the internal iliac. Passing 

 forwards along the side of the pelvis, it enters the lateral false ligament of the 

 bladder, where, after giving oflf one or more vesical branches, it ceases to be ]iervious 

 as it passes on to the side and upper part of the l)ladder. Thence it ascends, under 

 cover of the anterior false ligament, as a fibrous cord, to the umbilicus, where it is 

 joined by its fellow of the opposite side. As it lies in the lateral false ligament it 

 is crossed bv the vas deferens. 



2. THE VESICAL ARTERIES 



The vesical arteries are divided into the superior, middle, and inferior. 

 (1) The superior vesical artery — though usually described as a branch of the 

 internal iliac, inasmuch as it is api)arently given ofl:' from the anterior division of 



