This section is from the book "Diseases Of The Intestines", by Max Einhorn. Also available from Amazon: Diseases Of The Intestines A Text-Book For Practitioners And Students Of Medicine.
By intestinal obstruction is understood a great variety of conditions which, although unlike in character, have yet the common feature of mechanically causing an obstruction to the passage of contents along the intestine. Leichtenstern 1 distinguishes the following three groups with regard to the causation of the intestinal obstruction:
1. Occlusion* due to pressure from without or compression of the intestinal lumen in the full sense of the word. To this group belong incarcerations of the intestines in apertures, in slits, and in hernial openings; strangulation by pseudo-ligaments, the vermiform process, and diverticula; compression by tumors, by the mesentery, or by displaced abdominal organs. Rotations of the intestinal tube around its axis (torsions) and formation of knots also belong to this category.
2. Occlusion from within the intestinal lumen (obturation). The obturation may be produced either by gall stones, enteroliths, foreign bodies, hardened fecal masses, or by neoplasms of considerable size, especially polypi. Intussusception (involution of one coil of the bowel into another) also belongs to this class.
1 Leichtenstern: "Verengerungen, Verschliessungen und Lagever-anderungen des Darms." Ziemssens " Handbuch der speciellen Patho-logie und Therapie," Bd. vii., Leipzig, 1878.
3. Occlusions which originate from factors within the intestinal wall and causing narrowing of the lumen either directly or indirectly. Constriction may occur either in circular form (strictures) or as a result of flexions. Obstructions developing after chronic peritonitis, distortions, and angular bends of the intestine, cicatricial stenoses as well as those produced by neoplasms, belong to this class.
Notwithstanding the diversity and great multiplicity of the anatomical factors causing stenoses and obstructions of the intestines, the clinical picture and the consecutive lesions which they evoke greatly resemble each other. It will therefore perhaps be practical to give first the clinical picture of complete obstruction of the bowels (ileus) and of stenosis of the intestine, and then to discuss the different anatomical causes and also the differential diagnosis.