DISEASES OF THE BONES. 



413 



Fig. 703.- 

 ostosis. 



-Ex- 



1. Splint; 3. 3. 

 Enlargements 

 caused by Injury. 



Causes. — It may arise from whatever produces inflammation 

 of the bone, or arrests or suspends its nourishment. It is a frequent 

 sequtl of fracture in the ribs, sometimes from neg- 

 lect or mismanagement of poll-evil, or fistula of the 

 withers ; in cattle, sometimes from " foul of the foot." 

 Whatever destroys the periosteum may produce 

 caries. < 



Symptoms. — The surrounding tissues are swollen ; 

 there is an opening into the diseased bone, from 

 which acrid, badrsmelling matter discharges, in which 

 float speculse of disintegrated bone. On examining 

 the bone, it presents a fungus, which readily bleeds 

 when touched ; on pressing the finger into it, sharp 

 processes of bone are felt, which are the bone break- 

 ing up. The bone is easily punctured with a probe 

 or knife. 



1 Treatment. — This, in most cases, is a very tedious affair. In the 



first place, the wound must be 

 freely opened, and the parts 

 touched with dilute hydro- 

 chloric acid several time,s a 

 day. Mineral and vegetable 

 tonics must be given. When 

 practicable, as on the withers, 

 the diseased portion should be 

 cut off with a fine saw. Occur- 

 ring in a joint, we must en- 

 deavor to produce anchylosis 

 of the joint, the treatment of 

 which has been explained as 

 for spavins, etc. 



Necrosis of Bone. 



Necrosis is generally de- 

 fined to be the' entire death 

 or mortification of a bone. It 

 differs from caries, in which 

 the bone is discharged in particles, whereas in necrosis not unfre- 

 quently the whole bone dies, and becomes encased in a new bone of 

 exactly the same shape, which is perforated by numerous .holes, 

 through which the old bone exfoliates. 



Causes. — In man it not unfrequently arises from constitutional 



Fig. 704.— Splint, and 

 Small Wind-gall. 



Fig. 705.— A Splint 

 after Cure. 



