THE ABDOMEN 



837 



the obturator foramen, there is a break in the osseous attachment 

 of the fascia, which here joins the upper border of the obturator 

 membrane over the upper border of the obturator intemus, and so 

 converts the obturator groove into a canal for the passage of the 

 obturator vessels and nerve. At the upper and inner part of the 

 obturator foramen the fascia resumes its osseous attachment, but 

 falls more and more short of the pelvic margin, its connection with 

 the back of the body of the os pubis being in a direction down- 

 wards and inwards till it reaches a point just below the lower part 

 of the symphysis pubis. The fascia descends from the foregoing 

 line of attachment, closely covering the obturator internus, to be 



Parietal Pelvic Fascia 



Visceral Pelvic Fascia 

 Levator Ani 

 Anal Fascia 

 Obturator Internus 

 Parietal Pelvic Fascia 



Prostate Gland, with Urethra Alcock's Canal 



Fig. 363. — The Pelvic Fascia (Anterior View). 



attached as follows from before backwards : (i) to the pelvic aspect 

 of the ischio-pubic ramus near the subpubic arch, where it lies 

 on the mesial side of the obturator internus ; (2) to the inner margin 

 of the falciform process of the great sacro-sciatic ligament at the 

 lower part of the ischial ramus, and also to the great sacro-sciatic 

 ligament itself, where that is attached to the inner margin of the 

 tuber ischii ; and (3) to a portion of the great sacro-sciatic ligament 

 near its ischial attachment, and to the anterior margin of the 

 great sciatic notch. The lateral portion of the parietal pelvic fascia, 

 from its relation to the obturator intemus muscle, is sometimes 

 called the obturator fascia. From its lower attachment the fascia 

 is continued backwards and inwards over the great sacro-sciatic 

 foramen, pyriformis, and sacral plexus to the sacnun, as the fascia 

 of the pyriformis. As it covers the foramen it is perforated by the 

 gluteal, sciatic, and internal pudic vessels. 



At the anterior part of the pelvic cavity the fascia, after taking 

 attachment to the pelvic surface of the ischio-pubic ramus near 

 the subpubic arch, is continued inwards over that arch, where it 

 lies behind the .compressor urethrae muscle, and forms one half of 

 the postero-superior or deep layer of the triangular ligament, the 

 other half being formed by the corresponding portion of the fascia 

 of the opposite side. When it arrives at the urethra, it changes its 

 course, and passes backwards over the anterior border of the 



