THE MALE PERINEUM. 475 



the artery to the bulb about 3 cm. (i^ in. ) in front of the anus, and then about 1.25 

 cm. (}4 in.) below the subpubic ligament pierces the anterior layer of the triangular 

 ligament and divides into the artery to the corpus cavernosum and artery to the 

 dorsum of the penis ; it is accompanied by the pudic nerve, which divides in like 

 manner. Posteriorly this space is open, not being closed by any fascia except that 

 lining the under or superficial surface of the leva tor ani muscle in the ischiorectal 

 fossa. In the mid-line the continuation of the longitudinal fibres of the rectum 

 called the prerectal or recto-urethralis muscle blend with the fibres of the deep 

 transverse perineal muscle. 



Practical Application. The perineum is involved in extravasations of blood 

 and urine in cases of rupture of the urethra ; also in operations on the deep urethra 

 and bladder for the retention of urine from stricture ; also in operations for vesical 

 calculus, enlarged prostate, and disease of the seminal vesicles. 



Extravasation of Urine and Blood. Urinary extravasation results most often 

 from stricture and occurs almost always in front of the anterior layer of the triangular 

 ligament. The urine enters the superficial perineal space and is confined superficially 

 by Colics' s fascia and beneath by the triangular ligament. It is prevented from 

 going back into the ischiorectal space by the union of Colics' s fascia and the triangu- 

 lar ligament posterior to the superficial transverse perineal muscles ; it is prevented 

 from extending laterally by the attachment of Colics' s fascia to the ischiopubic rami ; 

 hence it works its way forward, distends the scrotum, and follows the spermatic cord 

 up over the crest of the pubis between the spine of the pubis and the median line. 

 Reaching the surface of the abdomen it is prevented from descending on the thigh 

 by the attachment of the deep layer of the superficial fascia (Scarpa's fascia) just 

 below Poupart's ligament, so it flows laterally and makes a collection in the flank of 

 each side above the iliac crests. It may also infiltrate the penis as far forward as the 

 glans.* The septum in the median line of the abdomen, perineum, and scrotum 

 hinders but does not prevent the passage of the urine from one side to the other. 

 In treating it, numerous free incisions are made down to the deep fascia. 



Rupture of the Urethra. This is produced by falling astride a hard object 

 and jamming the urethra against the subpubic arch, or it results from stricture. 

 The rupture almost always involves the urethra just in front of the triangular ligament 

 and sometimes a part of the membranous urethra. The superficial perineal space 

 becomes infiltrated with blood, and if urine is passed it follows the blood, collecting 

 between Colics' s fascia and the triangular ligament. 



If the membranous urethra is ruptured the blood and especially the urine may 

 escape into the deep perineal space between the layers of the triangular ligament. It 

 may break or leak through the anterior layer and enter the superficial perineal space ; 

 it may work backward into the ischiorectal regions ; it may work up and back 

 between the prostate and rectum or breaking through the deep layer of the triangu- 

 lar ligament it may work up and anterior behind the symphysis pubis, in the pre- 

 vesical space (of Retzius) between the peritoneum and transversalis fascia (see Fig. 

 476). Ruptured urethra is treated by perineal section or by a retained catheter. 



Perineal Section and Median Lithotomy. In these operations the bladder is 

 entered through an incision in the median line into the bulbomembranous urethra. 

 They are done to divide deep strictures, to allow the urine to escape in extravasation 

 and rupture of the urethra, to remove foreign bodies and calculi from the bladder, and 

 to remove enlargements of the prostate gland. The incision is to be made through 

 the raphe in the median line ; ordinarily it does not begin farther forward than 3 cm. 

 ( i ^ in. ) in front of the anus. As the central point of the perineum is 2 cm. in 

 front of the anus the incision passes through it and divides the posterior fibres of the 

 bulbocavernosus muscle but involves little if at all the erectile tissue of the bulb. 

 There is little bleeding if the incision is kept in the median line. The urethra is 

 entered about 2.5 cm. (i in.) from the surface, and the knife passed upward and 

 back through the membranous and prostatic urethra into the bladder, a distance of 

 6. 25 to 7. 5 cm. (2^ to 3 in. ) from the surface. In fat people or those with enlarged 

 prostates one may be unable to reach the interior of the bladder with the finger. 

 The membranous and prostatic urethra is distensible, so that when the former is 

 opened the finger can be introduced and pushed into the bladder. In children the 



