MALE PERINEUM 



it arbitrarily into two portions by drawing an imaginary 

 transverse line between the anterior parts of the ischial 

 tuberosities, immediately in front of the anus. Two triangles 

 are thus mapped out. The anterior of these may be appro- 

 priately called the urogenital triangle, because the most im- 

 portant objects which it contains are the urethra and the root 

 of the penis ; the posterior may be distinguished as the anal 

 triangle, from its containing the anal canal. 



r 



FIG. 127. Body in Perineal Posture. 



Preparation of Part for Dissection. To prepare the part for dissection, 

 a staff should first be introduced into the bladder. The dissector must 

 stand upon the left side of the subject. Having smeared the instrument 

 with oil, hold it lightly in the right hand and guide it gently along the 

 upper and right wall of the urethra. When the point of the instrument 

 reaches the inferior fascia of the urogenital diaphragm (O.T. triangular 

 ligament), a strong aponeurotic structure which is stretched tightly across 

 the pubic arch depress the handle, but use no force. Should any diffi- 

 culty be experienced, introduce the forefinger of the left hand into the 

 rectum to guide the point of the instrument along the membranous and 

 prostatic portions of the urethra. The most dependent part of the scrotum 

 should now be stitched to the prepuce of the penis, and dragging both 

 penis and scrotum forwards upon the staff, they should be fixed by means 

 of the twine to its handle. Lastly, fasten the handle of the staff to the 

 cord which passes behind the flexed knee-joints of the subject. 



The anal canal should then be slightly distended with tow, and the 

 orifice of the anus stitched up. 

 i 22 a 



