492 HERNIA. 



herniae may become of considerable size, and two cases are recorded in 

 one of which the opening of the hernial sac was 13 J inches in length 

 and 18 inches in width, and in the other 28 inches in length and 24 

 inches in width. The latter is the largest ever recorded. 



Complications. Complications are not always grave. If the hernia 

 is little marked the function of the rumen is not greatly affected and its 

 rhythmic contraction continues. When the original injury has caused 

 rupture of the muscular tissue of the rumen, and the mucous mem- 

 brane has passed into the opening, it may become strangulated and 

 gangrenous. 



Finally, if the mucous membrane has been torn at the same time 

 as the muscular tissue (which is very uncommon), alimentary material 

 may escape into the subcutaneous connective tissue, setting up either 

 cellulitis and death by infection, or suppuration ; abscess formation and 

 rupture towards the exterior, followed by a persistent sinus ; or again 

 septic peritonitis, and death. 



The same results may occur when the hernia is in a very low portion 

 of the abdomen ; food accumulates in it, becomes stagnant there, sets up 

 local irritation and inflammation, and sometimes abscess formation with 

 external discharge, followed by fistula of the rumen. 



Gastric fistula without secondary complications is compatible with 

 life, and even with fattening for slaughter, provided the peritoneum 

 covering the rumen becomes attached to the opposing surface of peri- 

 toneum around the perforation. The fistula is then surrounded by a 

 circular mass of fibrous tissue, forming a kind of sleeve. 



Lesions. The lesions are the same in all herniae. They consist 

 primarily in rupture of the abdominal wall, and, later, of sero-san- 

 guinolent infiltration of the margins of the wound, similar to that ac- 

 companying the formation of an abscess. Hernial swellings are of 

 very varying size. Apart from cases similar to those above described, 

 the swelling may be simply an inch or two in diameter, or it may 

 attain the dimensions of a hen's egg or even of a man's fist. 



When the abdominal tunic only has been ruptured, as is most fre- 

 quently the case, the peritoneum is thrust outwards and forms a cavity, 

 the hernial sac. This sac is absent when the peritoneum is ruptured. 

 Little by little the surrounding connective tissue forms a pseudo- serous 

 hernial sac. But, nevertheless, in some cases there may be found, im- 

 mediately under the skin, the mucous membrane of the rumen in a 

 state of congestion and ready to become gangrenous. 



Diagnosis. Easy in all cases. 



Prognosis. Very variable. In the case of small herniae situated in 

 the lateral regions of the abdomen the prognosis is not very grave. If, 

 however, the rupture is wide, and situated in the lower portion of the 



