THE MALE PERINEUM. 



473 



sides, and a line joining the two behind. It is closed by a stout fibrous membrane 

 called the triangular ligament. 



The central point of the perineum is in the median line 2 cm. (^ in.) in 

 front of the anus; it marks the posterior edge of the triangular ligament in the median 

 line, and is the point of junction of the anteroposterior and transverse muscles. 



Perineal Fascias. There are four perineal fascias, viz.: (i) the superficial 

 layer of the superficial fascia ; (2) the deep layer of the superficial fascia, called also 

 Colics' s fascia ; (3) the superficial layer of the deep fascia, or triangular ligament ; 

 and (4) the deep layer of the triangular ligament or pelvic fascia (Fig. 475). 



The superficial layer of the superficial fascia is the subcutaneous fatty tissue, 

 and is continuous with that of the surrounding parts and the dartos. When thick it 

 makes operations on the deeper structures more difficult and sometimes impossible. 



The deep layer of the superficial fascia or Colles' s fascia is the fibrous under 

 surface of the fatty superficial layer. Posteriorly it unites with the posterior edge of 

 the triangular ligament; laterally it is attached to the ischiopubic rami; and anteriorly 

 it is continuous with the under surface of the dartos of the scrotum, passes forward 





Deep layer of superficial fascia 

 (Colles) 



Inferior pudendal nerv 

 External perineal nerve 



Internal perineal nerve 



Superficial perineal artery 



Superficial perineal spare and 



triangular li&jament (superficial 



layer) 



Transverse perineal art 1 



Central point of perineu 



Coccy 



Dorsal artery of penis 

 Ischiocavernosus muscle 



Bulbocavernosus muscle 

 -Bulb 



Deep perineal space and 



compressor urethrcc muscle 



Artery to the bulb 



Cowper's gland 



Deep transverse perineal muscl 



Internal pudic artery 



Superficial transverse perineal 



muscle 



External sphincter ani 



Levator ani 



Inferior hemorrhoidal arteries 



and nerves 



FIG. 475. The male perineum. The superficial perineal space is shown on the left and the deep perineal space 



on the right. 



to form the suspensory ligament and fibrous sheath (Buck's fascia) of the penis, 

 covers the spermatic cord, and is continuous with Scarpa's fascia (deep layer of the 

 superficial fascia) of the abdomen. 



The anterior layer of the triangular ligament is a firm fibrous membrane stretch- 

 ing from one tuberosity to the other, and attached to the ischiopubic rami on the 

 sides forward to the pubic arch. Between its upper edge and the symphysis runs the 

 dorsal vein of the penis, the dorsal artery and nerve piercing it a little lower and to 

 the outer side; 2.5 cm. (i in.) below the symphysis is the urethral opening with 

 the opening for Cowper's ducts close to it below, and those for the vessels to the 

 bulb close to it above. The superficial perineal vessels and nerves pierce its pos- 

 terior edge. The posterior edge of the triangular ligament blends with the posterior 

 edge of the deep layer of the superficial fascia (Colles). 



The deep layer of the triangular ligament is a continuation downward of the 

 pelvic fascia. It begins above on the inside of the pelvis, covering the obturator 

 muscle as the obturator fascia ; it then passes onto the levator ani muscles as the 

 recto-vesical fascia. As the levator ani muscles do not meet in front, the gap between 

 them is filled in at the median line below or posteriorly by the termination of the 



