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The Internal Iliac Artery 



anastomoses with the obturator artery. It is covered by the gluteus 

 maximus, which it freely supplies, anastomosing in it with the gluteal 

 artery. Before leaving the pelvis the sciatic artery may give off some 

 branches to the bladder and rectum ; but its first-named branch is the 

 coccygeal, which pierces the great sacro-sciatic ligament to supply the 

 lower part of the origin of the gluteus maximus and the integument 

 over it. The other named branch is the conies nervi ischiatici, which 

 enters the great sciatic nerve and anastomoses with the perforating 

 arteries and with superior muscular branches of the popliteal ; it is 

 an important branch in the collateral circulation. 



To find upon the surface of the buttock the spot, at which the 

 sciatic artery is leaving the pelvis, see below. 



The other terminal branch of the anterior division of the internal 

 iliac is the internal pudic artery. 



The posterior trunk of the internal iliac gives off the gluteal artery, 

 which, passing through the upper part of the great sacro-sciatic notch, 

 at once divides into a superficial and a deep branch. The former 

 appears between the gluteus medius and pyriformis, and ends in the 

 supply of the gluteus maximus, anastomosing with the sciatic. The 

 deep part of the gluteal artery remains under 

 cover of the gluteus medius, and divides into 

 a superior and an inferior branch, both of 

 which run towards the interval between the 

 front of iliac crest and the great trochanter, 

 where they anastomose with ascending 

 branches of the external circumflex. The 

 upper branch runs close around the border 

 of the gluteus minimus, and, sending 

 branches through the medius, anastomoses 

 with the deep circumflexa ilii. The lower 

 branch may anastomose with the sciatic as 

 well as with the external and internal cir- 

 cumflex. 



Surface-marking-. The spot at which 

 the gluteal artery leaves the pelvis may be 

 marked on rotating the thigh inwards and 

 drawinga line, A G, from the posterior superior 

 iliac spine to the great trochanter. The 

 junction of the inner, A E, with the middle 

 third, E F, of this line gives the position of 

 the artery. 



The pudic artery lies over the spine of 

 the ischium. To find it, draw a line, A D, from the posterior superior 

 iliac spine to the outer side of the tuber ischii, and take the junction of 

 the middle and lower thirds, C. The junction of middle and uppei 

 thirds, B, marks the point of emergence of the sciatic. (Holden.) 



The following rationale may make this scheme more easily re- 



