PARTICULAR FRACTURES 239 



by levering up the depressed fragments. This will require that a small 

 piece of bone shall be removed with a trephine from a suitable position 

 outside the fracture area, and a lever properly padded at the point intro- 

 duced into the opening and the depressed bone raised into its normal 

 position. If the bone should be broken into small pieces replacement 

 will be greatly assisted by manipulating them from the outside, while 

 they are being raised by the lever from within. It may be that one 

 or more of them will require to be removed. If so it should be done at 

 once under strict antiseptic precautions; but it must be pointed out that 

 since no muscles are attached here, and the bone is not exposed to any 

 moving force, or called upon to support weight, there is nothing to 

 occasion displacement when once adjustment of the broken parts has 

 been effected. 



Hsemorrhaoie into the frontal sinuses is a common result of fracture 

 of this part of the frontal bone, and should the operation of trephining 

 be called for an opportunity will then be aflbrded for washing out the 

 blood, for which a tepid antiseptic solution should l)e employed. 



Chronic disease of the bone is an occasional consequence of this accident, 

 and must be dealt with accordino' to the indications of the case. 



FRACTURE OF THE LOWER JAW 



Fracture of the lower jaw may take place through the neck of the right 

 branch or the left, or both. It may proceed vertically through the body 

 and divide or separate the two branches from each other. It may pass 

 transversely through the body of the bone behind the incisor teeth, or it 

 may detach the styloid process, or sever the condyle from its branch, and 

 in various other ways the bone may be chipped or broken. 



External violence in one or another of its many forms is accountable 

 for this mishap, to which in rare instances the bone is predisposed by 

 disease. Kicks from other horses, falls, and collisions are the more 

 common causes, but it sometimes results from the teeth becoming fixed 

 in narrow spaces, and from the careless use of the gag while performing- 

 dental and other operations on the mouth and throat. In young colts, 

 the parts of whose bones are not yet firmly united together, one branch 

 is sometimes partly or completely torn away from the other through 

 their connection at the body. At the same time the central incisor 

 teeth alone or together with others are loosened, and perhaps also more 

 or less displaced. 



Symptoms. — In vertical fracture through the body of the bone there 

 is at first considerable flow of saliva from the mouth. The lower lip is 



