Practical Anatomy, a Manual of Dissections

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1881 Excerpt: ... bladder with the urethra and the rectum having been removed as directed, should be laid on the table with the rectum uppermost, and that viscus should be filled with cotton-wool and cleaned, and its muscular fibres exposed. The Bectum is about eight inches long and is generally largest just above the anus, which will be seen to be surrounded by the sphincter muscle. The arrangement of the peritoneum upon the rectum has been already described (p. 263), and the longitudinal muscular fibres will be now seen to differ from those of the rest of the large intestine, in being spread all around it instead of being collected in three bands. The internal or circular muscular fibres become thickened near the anus to form the internal sphincter muscle, which is best seen when the bowel is opened. The numerous arteries entering the rectum are derived from three sources--the superior hemorrhoidal artery from the inferior mesenteric, which may be traced to within three inches of the anus; the middle haemorrhoidal from the internal iliac; and the inferior haemorrhoidal from the internal pudic. The veins open both into the vena porta and the internal iliac vein. The intestine being opened along its unattached border, the mucous membrane will be seen to be smooth, except near the anus, where it is thrown into longitudinal folds by the sphincter. Here also it frequently happens that hemorrhoids exist. Three or four transverse ridges of mucous membrane (valves or folds of Houston) will be found from three to six inches above the anus, which occasionally cause difficulty in the introduction of a bougie or rectum, tube. The rectum is now to be. carefully dissected from the bladder, which is to be moderately distended with air, and the under surface of the penis and bladder &quo...