POSTERIOR PART OF LOWER EXTREMITY. 



373 



The Inferior Gluteal Nerve. A branch of the sacral plexus. Leaves the 

 pelvis by the greater sacro-sciatic foramen, below the pyriformis, and supplies 

 the gluteus maximus. (Fig. 258.) 



The Lesser Sacro-sciatic Foramen. The notch of the same name is con- 



Gluteus medius 



Pyriformis 

 Gemellus superior 



Gemellus inferior 

 Quadratus femoris 



Gluteua maximus 



Vastus externus 



Biceps 



Crureus 



Short head of biceps 

 Plantaris 



Oastroonemiue 



Obturator interims 



Adductor magnuS 



FIG. 259. THE EXTERNAL ROTATORS AND THE HAMSTRING MUSCLES. 



verted into this foramen by the greater sacro-sciatic ligament. (Fig. 259.) It trans- 

 mits the internal obturator tendon and its nerve, the internal pudic nerve, artery, 

 and vein. (Fig. 258.) The vessels and nerve lie above the tendon. To trace these 

 structures properly, it will be necessary to remove the gluteus maximus from the 



