34 



(s) A. glutea anterior is the largest branch of the iliaca interna. It 



arises nearly opposite the iliolumbalis, passes through the greater sacro- 

 sciatic foramen and immediately enters the gluteal muscles by several 

 branches. These branches cannot be demonstrated until the gluteal 

 muscles have been dissected. Frequently one of the radicals of the N. 

 obturatoria (from the 6th lumbar, PL VII, i6) crosses the ventral face of 

 the A. glutea anterior, close to its origin from the iliaca interna. 



(6) A. circumflexa femoris lateralis (iliaco-femoral artery) is one 

 of the terminal branches of the iliaca interna. To expose the vessel, draw 

 aside the distal portion of the psoas magnus ; transect the iliacus and draw it 

 aside. The artery crosses the shaft of the ilium a little dorsal to the in- 

 sertion of the psoas parvus and enters the quadriceps femoris group of 

 muscles between the rectus femoris and the vastus externus. It supplies 

 branches to the psoas magnus and iliacus, rectus femoris, tensor fasciae 

 latae, vastus externus and medius and the superficial and middle gluteal 

 muscles. The artery is accompanied by two large veins. 



(7) A. obturatoria (PL V, 38) is the inner terminal branch of the A. 

 iliaca interna. It passes posteriorly on the inner or pelvic surface of the 

 shaft of the ilium along the ventral border of the iliac portion of the M. 

 obturator intemus. The obturator vein and nerve accompany the artery. 

 At the anterior border of the obturator foramen the artery, vein and nerve 

 dip beneath the M. obturator internus (PL V, 18'). Cut the overlying 

 portion of this muscle close to its origin and turn it aside. In its course 

 beneath the M. obturator intemus the artery gives off small twigs to it; 

 also a larger branch which passes through the obturator foramen and is 

 supplied to the hip joint. At the very posterior part of the obturator 

 foramen the obturator artery gives off a small branch which passes posteri- 

 orly on the dorsal surface of the ischium, to the ischial arch, where it anasto- 

 moses with a branch of the A. obturatorius that extends along the ventral 

 face of the ischiiim; it also anastomoses by a small branch with the A. 

 pudenda interna. The extrapelvic portion of the A. obturatoria is deeply 

 covered by the muscles of the inner side of the thigh and can be only par- 

 tially exposed at present. First dissect the M. gracilis, beginning at its 

 posterior border; free it from the underlying muscles and at the same time 

 transect it a little below its middle. Turn back the proximal portion 

 of the muscle noting the blood-vessels and nerves that enter it. Now 

 beginning at its posterior border, cut the muscle about two-thirds of the 

 way across, close to its attachment to the pelvis, in order to expose clearly 

 the origin of the adductor magnus. (The adductor magnus as here used 

 includes the adductor parvus of some writers). Note the deep inguinal 

 lymph gland 12 to 15 cm. in length, that lies in the space between the 



