300 FRACTURES. 



Javr. 



The lower jaw is sometimes chipped by the injudicious use of 

 severe bits and tight curb-chains. Usually, the injury is not de- 

 tected at the timevif infliction. There is swelling, pain and diffi- 

 culty in feeding. The wound in the gum is generally marked by 

 a round, red eminence. The splintered portion of bone may be 

 felt with the probe, in which case, much time will be saved by 

 removing it with a bone forceps. Any diseased portions of bone 

 should be scraped off and aa antiseptic (p. 67) applied several 

 times a day. One or both branches of the lower jaw may be 

 broken ; the usual seat of the fracture being the " chin-groove " (in 

 which the curb chain should rest, when a curb or Pelham is used). 

 When the lower jaw has been broken right across, it will require 

 a special form of splint, which can be obtained from a veterinary 

 instrument maker. The general principles of treatment for frac- 

 tures (p. 295) should be observed; the animal fed on soft food; 

 and the part kept at rest. 



Lieg. — See " Cannon Bone," page 299 ; " Pastern bones," page 

 300; " Femur," page 299 ; and " Tibia," page 312. 



Navicular Bone. 



It is probable that this fracture occurs only in cases of navicular 

 disease (p. 205). The symptoms are those of " dropped elbow " 

 (p. 311), and heat of the affected part, with absence of crepitus 

 (p. 295) about the shoulder. Treatment is of no avail. 



Pastern Bones. 



This accident (split-pastem) affects the long pastern bone far 

 more frequently than the short one, and generally occurs from the 

 violent concussion of fast galloping, which is sometimes aided by 

 a diseased and brittle condition of the bone. Horses galloped, 

 particularly on hard ground, after a long rest, are very liable to 

 this accident, which I have seen occur on several occasions to 

 horses in India that had broken loose after having been recently 

 landed from a ship in which they had been imported, and where 

 they had been obliged to stand for a month or longer. Their en- 

 forced idleness had no doubt affected the strength of their bones, 

 and in the unwonted exercise tliey had naturally lost to some 

 extent their accustomed skill in saving their limbs from the ill 

 effects of concussion. The ajiimal pulls up very lame, the toe only 

 being brought near the ground. The absence of injury to the 



