168 THE STOCK owner's ADVISER. 



tween the interior of both bones. In this manner the process of 

 an anchylosis is commenced. 



Treatment. — Cut down upon and expose the diseased struc- 

 ture; scrape the diseased bone until all carious portions are re- 

 moved. Where extensive disease exists, scraping with the bone- 

 spoon will rarely suffice. In such case a portion of bone must be 

 removed by means of the bone forceps or bone saw, after which 

 the parts may be touched with diluted hydrochloric acid. If the 

 presence of caries in an articulation be suspected, the treatment 

 should, of course, be different. If it exists in a true hock joint, a 

 cure cannot be effected, but if in a gliding articulation the treat- 

 ment consists in hastening the process of anchylosis. Give rest 

 and use the actual cautery. Red iodide of mercury, one part of 

 lard to five parts of mercury, may be used. 



NECROSIS. 



Definition is death of bone. It corresponds to mortification of 

 the soft structures, and is distinct from caries, as mortification 

 is from ulceration. Xecrosis is due in a large majority of cases to 

 injury, either directly or indirectly received, and is very rarely 

 due to constitutional disturbance. The necrosed portion presents 

 a white, waxy appearance, sonorous when struck by a probe; ex- 

 posed to the atmosphere, before separation, it becomes changed 

 in color. If the skin should be uncut, an abscess soon forms, 

 which, if left alone, discharges itself; if the ulcer is examined 

 with a probe, the bone will be found bare and perhaps loose. The 

 abscess does not heal until the loose portion, called an exfoliation, 

 is removed; in fact, there is now a fistulous communication be- 

 tween the dead bone and the atmosphere. 



Free vent must be given to the pus, which is curdy in consist- 

 ence, and when the bone is found to be loose should be remoA-ed 

 by the forceps. 



!N^ecrosis is often seen in connection with the lower jaw. It 

 sometimes affects the shafts of the long l)ones, more especially the 

 metacarpals, metatarsals, and scapula. 



