THE PELVIS. 



DISSECTION OF THE PELVIS. 



Inspect and become familiar with the following : 



1. The pelvic contents are covered by peritoneum. 



2. The rectum is on the posterior wall of the pelvis. 



3. The bladder is on the anterior wall of the pelvis. 



4. The obturator nerve and vessels are on the outer wall. 



5. Tlie ureter crosses into the pelvis and can be seen. 



6. The uterus and adnexa are between bladder and rectum. 



7. The broad ligament contains the uterine adnexa. 



8. The recto-vesical poucli is between the rectum and bladder. 



9. The peritoneum does not cover the anterior surface of bladder. 



10. Retsins' space is between bladder and pubes. 



1 1. The recto-vaginal, recto-uterine, and cul-de-sac of Douglas. 



i 2. Douglas 1 cul-de-sac is between the rectum and vagina and uterus. 

 13. Ilcnm and great amentum gravitate into the pelvis. 

 Follow this order in your dissection : 



1. The peritoneal ligaments of the bladder, rectum, and uterus, and the 

 sympathetic nerves from the pelvic part of the hypogastric plexus to the same 

 viscera, noticing they invariably follow the arteries to the organ, and take the 

 name of the artery. 



2. The pelvic fascia and its subdivisions and modifications incident to use, 

 remembering, as you must, that growth is the correlative of function. Notice, 

 too, that pelvic fascia is condensed subperitoneal connective tissue. The upper 

 or uncondensed portions of the pelvic fascia contain fat. 



3. Study the relations of the psoas carefully ; as nearly as may be, follow 

 the steps just as given in the sequel, for this is the order in which you will meet 

 all these various structures in your dissection. 



4. The lumbar plexus ; its location in the substance of the psoas muscle ; its 

 formation by the four upper lumbar nerves and a communicating branch from 

 the twelfth thoracic ; and its immense distribution. 



5. The internal iliac artery and all its branches, where the same escape from 

 the pelvis, the spinal nerves they accompany, and the source of the sympathetic 

 nerves that encircle them to supply the viscera. 



6. A view of the ischio-rectal fossa from above, by cutting the origin of the 

 levator ani muscle at the white line and looking in on the obturator interims 

 muscle that forms its outer wall. 



7. The sacral plexus, its location, relations, communications, and branches of 

 distribution, and where these large branches escape from the pelvis. 



8. In addition to the above, make dissection and study of the iliacus (origin 

 of), the pyriformis, the levator ani, the obturator internus, the white line of the 

 pelvis, and the delamination in the obturator fascia, called Alcock's canal. 



In order to estimate the peritoneal ligaments in any peritoneal region, ask 

 yourself how many viscera of considerable size grew up behind this membrane 



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