484 ABDOMEN 



the level of the visceral layer into the perineum, where it is 

 still spoken of as parietal pelvic fascia. The dissector should 

 commence his examination of the fascia by noting that the 

 parietal part is continuous above with the fascia on the psoas 

 major muscle. Traced downwards from the psoas, it can be 

 followed to the level of a line extending from the lower part 

 of the back of the symphysis to the spine of the ischium, 

 /.<?., to the level at which the visceral layer springs from its 

 inner surface. Traced backwards, it passes lateral to the 

 hypogastric vessels and then across the front of the sacrum 

 to the opposite side, concealing the sacral plexuses and the 

 piriformes muscles. 



When it is traced forwards it will be found to terminate, 

 anteriorly, along a curved line which commences at the medial 

 side of the ilio-pectineal eminence, on the inner surface 

 of the superior ramus of the pubis, descends to the lower 

 border of the symphysis pubis, and then ascends to a corre- 

 sponding point on the opposite side. The parietal fascia is 

 deficient, therefore, on the anterior boundary of the lower part 

 of the cave of Retzius. Each half of this anterior border of 

 the parietal fascia is separable into three parts : A lateral 

 part, where the fascia blends with the periosteum on the pelvic 

 surface of the superior ramus of the pubis ; an intermediate 

 part, below the highest portion of the obturator foramen, where 

 the fascia turns over the upper border of the obturator internus 

 and runs outwards into the thigh, forming the lower wall of 

 the obturator canal ; a medial part, which is attached to the 

 periosteum on the pelvic surface of the body of the pubis. 



Turning next to the visceral layer, the dissector will find as 

 he traces it medially, in the posterior part of the pelvis, that the 

 rectum sinks into its substance. In front of the rectum it is 

 carried over the upper part of the vagina on to the uterus, and 

 in front of the uterus it is lost on the urinary bladder. Still 

 more anteriorly, it can be followed across the median plane to 

 the opposite side. In this last part of its extent two thickened 

 bands of its substance, one on each side of the median plane, 

 extend from the back of the pubis to the anterior border 

 of the bladder. Those bands are the medial pubo-vesical 

 ligaments or anterior true ligaments of the bladder, already 

 referred to. The dissector should note that the attachment 

 of the visceral layer to the back of the body of the pubis lies 

 at a higher level than the attachment of the anterior border 



