338 VETERINARY SURGICAL OPERATIONS 



pursued. The first and most desirable one is extirpation 

 of the broken segment with all of the fibrous tissue that sur- 

 rounds it, and the second is drainage of the pus cavity below 

 the segment and the insertion of a seton to maintain the 

 drainage orifice until the sac has safely cicatrized. The first 

 should be chosen when the bone is small, and the second 

 when the size of the bone and its proximity to the abdomen 

 would render its extirpation hazardous. 



In either case the operation should, if possible, be per- 

 formed in the standing position, because decumbency 

 changes the anatomical relations in the most confusing man- 

 ner imaginable. The stocks are excellent. If the recumbent 

 position is found necessary the English hopples are far the 

 best, because with them the leg is extended and the field 

 handy to approach. 



Th first step is to make an incision from the external 

 angle of the ilium, where the fistulous orifice is located, 

 downward and backward until its lowest part overlaps the 

 segment. The incision may be from four to ten inches long, 

 according to the size and position of the segment. 



In the next step a part of the bone is exposed by dis- 

 section and then grasped with large tumor forceps. With 

 these the bone is drawn upon and turned about as the 

 tedious dissection to release it entirely is complete. If found 

 to have branches extending into inaccessible positions, it may 

 be sectioned with a saw and extirpated piece by piece. 



Having abstracted every vestige of the segment, the at- 

 tention is directed to the pus cavity. If found to extend 

 into parts where the pus will not drain by gravity, a depend- 

 ent drainage is provided. 



The cavity is packed with antiseptic cotton and closed 

 temporarily with sutures to retain it. This dressing is re- 

 moved at the end of twenty-four hours and the cavity treated 

 with abundance of antiseptic powder until cicatrization is 

 well advanced. 



When extirpation is not thought advisable, attempt is 

 made to locate the bottom of the tract by probing, and an 

 opening made at the level indicated by the depth of the 

 probe. To facilitate the probing the original orifice may be 

 enlarged. When the lower opening has reached the tract 

 below the segment, a seton is passed through it from the 

 original orifice. The seton is renewed every few days but is 

 not dispensed with entirely for three to four weeks. The 

 results from this method are uncertain. 



