1280 



THE UEO-GENITAL SYSTEM. 



Urinary bladder 



Symphysis pubis 



Corpus cavernosum_ 

 penis' 



Corpus cavernosuni 

 urethras' 



Bulbo-cavernosus 

 muscle 



Rectum 



Internal sphincter ani 

 External sphincter ani 

 Anal canal 



opening lies on a level with the upper margin of the symphysis pubis, and the 

 openings of the ureters lie almost on a level with the plane of the pelvic brim. 

 The obliterated portions of the umbilical arteries are more intimately related to 

 the bladder in the foetus and child than in the adult, and lie close against its 

 sides as they pass upwards towards the umbilicus (Fig. 999). 



Peritoneal Relations and Connexions of the Bladder. We have already 



seen that the 

 superior surface of 

 the empty bladder 

 is covered by peri- 

 toneum, which 

 leaves it along the 

 lateral border on 

 each side to reach 

 the pelvic wall at 

 about the level of 

 the arcus ten- 

 dineus or white line 

 of the pelvic fascia. 

 To this peritoneal 

 reflection the term 



External sphincter ani lateral false (or peri- 



toneal) ligament is 

 often applied. The 

 lateral ligaments of 

 opposite sides are 

 continuous in front, 

 at the bladder apex, 

 where the periton- 

 eum is conducted 

 over the fibrous 

 cord of the urachus 

 to reach the anterior 

 abdominal wall, 

 forming the so- 

 called superior false 

 (or peritoneal) liga- 

 ment. When the 

 bladder is empty 

 the level of this 

 anterior reflection 

 lies just behind, or 

 just below, the 

 upper margin of the 

 symphysis pubis. 



FIG. 998. MEDIAN SECTION THROUGH THE PELVIS OF NEWLY BORN CHILD. When the bladder 

 A, Male, and B, Female. becomes filled the 



level of the peri- 

 toneal reflection forming the superior false ligament is raised upwards, and may 

 reach a point two inches, or more, above the upper margin of the symphysis pubis. 

 Similarly, the line along which the lateral peritoneal ligament reaches the pelvic 

 wall is also carried upwards in distension of the bladder, and may reach the level 

 of the ductus deferens and of the obliterated umbilical artery. 



When the bladder is empty the peritoneum is carried downwards upon the side 

 wall of the pelvis as low as the lateral border of the organ, and lines a shallow 

 depression which receives the name of paravesical fossa. This peritoneal fossa lies 

 below the level of the obturator peritoneal fossa (p. 1269), from which it is separated 

 by the ductus deferens. As the bladder fills, the peritoneum is raised off this part 

 of the pelvic wall, and certain structures, such as the obturator vessels and nerve 



Urinary bladder 



Symphysis pubis 



Vagina 

 Urethra 



Carina urethralis 



Labium minus 

 pudendi 



Uterus 



Rectum 



Internal sphincter ani 



External sphincter ani 

 Anal canal 



External sphincter ani 



