384 The Rectum 



the bowel the first part ends at the middle of the third vertebra of 

 the sacrum.) 



The middle piece lies in the lower part of the sacro-coccygeal 

 hollow, with some of the pyriformis and sacral plexus behind it. In 

 its anterior bend rest the base of the bladder, the vesiculae seminales 

 and vasa deferentia, and the prostate gland, or the vagina and the 

 cervix uteri. This part of the bowel is securely fixed, and is very 

 capacious. It ends at the tip of the coccyx. 



The third part, about \\ in., turns back from the prostate or the 

 vagina to the anus. It is surrounded by the (striated) external 

 sphincter ani, and has supporting and fixing it on either side the 

 levator ani with its two layers of pelvic fascia (p. 363). The urethra 

 is separated from it by the perineum or by the vagina. This is by 

 far the narrowest piece of the large intestine, but it is very dilatable, 

 nevertheless. 



On introducing the finger about i in. into the rectum the apex of 

 the prostate gland can be felt, and just in front of and below this one 

 can detect the beak of the catheter in the membranous urethra ; and 

 should the instrument wander thence into a false passage its beak can 

 be felt just in front of the thin rectal wall. The finger can also ex- 

 plore the lobes of the prostate, detecting chronic hypertrophy, acute 

 inflammation, or the bogginess of a prostatic abscess. The vesicular 

 seminales and the vasa deferentia can also be searched for tubercular 

 or simple inflammatory enlargement ; and even a small stone may be 

 occasionally made out in the bladder or impacted at the orifice of the 

 ureter. Also the degree of distension of the full bladder may thus 

 be estimated. Information can also be obtained regarding fracture of 

 the coccyx, and of the connections of a sacral or pelvic tumour. In 

 the case of a tumour in the anterior wall of the rectum information 

 must be sought by thorough digital examination when a sound is in 

 the bladder, and the index-finger is in the vagina. 



In supra-pubic operations upon the bladder that viscus is rendered 

 much more accessible by gradually distending an india-rubber bag pre- 

 viously inserted in the rectum. Thus the anterior wall of the bowel 

 and the base of the bladder are lifted up. 



As remarked elsewhere (p. 386), a patulous condition of the anus is 

 a strong suggestion of the existence of stricture, and Mr. Bryant has 

 recently shown that a cavernous condition of the rectum ballooning 

 he calls it is of like clinical import. Having no work to do, the 

 muscular coat below the level of the stricture (which is then found high 

 in the rectum, or which exists in the sigmoid flexure) becomes relaxed, 

 and the wall widely yields all around the bowel. 



Serous coat. The arrangement of peritoneum is like that 

 obtaining in the duodenum the first piece being almost completely 

 invested, the second part being covered in front, \\h,Ut the third 

 piece has no serous coat. In the rectum, however, it is only the 



