THE LOWER EXTREMITY, POSTERIOR. 613 



outward and forward between the gluteus medius and mini- 

 mus muscles ; the superior keeping close to the bone along 

 the origins of the muscles, the inferior keeping company 

 with the superior gluteal nerve. (3) Besides these branches, 

 the gluteal artery gives off within the pelvic cavity small 

 vessels to the obturator internus, pyriformis, levator ani, 

 and coccygeus muscles and the pelvis itself. 



The gluteal artery anastomoses with the lateral sacral, 

 sciatic, deep circumflex iliac, and the external circumflex 

 (of the profunda). 



The Internal Pudic Artery. See page 411. 



The Sciatic Artery. Figs. 112, 114, 126, 127. 



This is the larger branch of bifurcation of the anterior 

 division of the internal iliac. It comes through the great 

 sacrosciatic foramen below the pyriformis muscle and 

 passes downward under the gluteus maximus to terminate 

 in the upper part of the thigh. 



It supplies numerous branches to the surrounding parts, 

 a few of which are named. 



(i) The coccygeal branch; this pierces the great sacro- 

 sciatic ligament, and supplies the gluteus maximus and the 

 superficial parts over the coccyx and sacrum. (2) The 

 anastomotic, a long slender branch to the great trochanter, 

 around which it anastomoses with the gluteal, external cir- 

 cumflex, ascending branch of the internal circumflex, and 

 the first perforating of the profunda. It supplies the exter- 

 nal rotators of the thigh and the hip joint. (3) Comes 

 nervi ischiadici, a small branch which supplies the great 

 sciatic nerve. (4) Numerous cutaneous branches below 

 the gluteus maximus. The sciatic artery through its lower 

 branches anastomoses with the first perforating of the pro- 



