PELVIS 631 



The former can be lifted into the pelvis and the latter can be 

 forced downwards much as the two segments of a folding 

 door are displaced in opposite directions, and thus a passage 

 is made for the exit of the child (Berry Hart). The dissector 

 should also note, as a matter of clinical importance, that, whilst 

 the urethra and the anterior wall of the vagina are closely bound 

 together and cannot be separated except by the use of the 

 knife, the posterior wall of the vagina and the anterior wall of 

 the rectum are only loosely united together and can easily be 

 torn apart. 



Vesica Urinaria (The Bladder). The female bladder has 

 normally a smaller capacity, and it lies at a somewhat lower 

 level in the pelvis than the male bladder, but its shape when 

 empty and slightly contracted is the same as in the male, i.e. 

 it has the form of a triangular pyramid possessing a superior 

 surface, two infero-lateral surfaces, a fundus or base, and an 

 apex. The superior surface is covered by peritoneum. It 

 is bounded by two lateral borders which separate it from 

 the infero-lateral surfaces, and by a posterior border which 

 separates it from the base. The two lateral borders converge 

 anteriorly and meet at the apex, from which a fibrous cord, 

 the median umbilical ligament (urachus) passes up the posterior 

 surface of the anterior abdominal wall to the umbilicus. The 

 urachus is the remains of the allantois of the foetus. The 

 lateral borders meet the posterior border of the upper surface 

 at the lateral angles of the bladder where the ureters enter 

 the wall of the viscus. The infero-lateral surfaces and the 

 anterior border which separates them are devoid of peritoneum. 

 They form the posterior wall of the lower part of the cave 

 of Retzius, and are separated from the back of the symphysis 

 and the posterior surfaces of the pubic bones by a layer of 

 loose extra-peritoneal fat. The term retro-pubic pad is applied 

 to that portion of the fatty tissue which intervenes between 

 the back of the symphysis pubis, the upper surfaces of the 

 medial pubo-vesical ligaments, and the anterior border of 

 the bladder. To examine the relation of the fundus of 

 the bladder to the uterus and vagina the student must cut 

 through the peritoneum at the bottom of the recto-vesical 

 excavation, and then with the aid of the knife separate the 

 bladder from the front of the neck of the uterus and 

 the upper part of the anterior wall of the vagina. Whilst 

 he is dividing the peritoneum he should notice that the 

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