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CHAPTER XIII. 



Fractures. 



fractures in general anterior iliac spine back— buttock, 



point of the cannon bone femur hip, point of the 



jaw leg navicular bone pastern bones pedal bone 



pelvis ribs ^first rib shoulder blade tail thigh 



tibia — "trapezium. 



Fractures in General. 



As fractures of the bones of the horse are, as a rule, but little 

 amenable to treatment, owing to the difficulty of reducing and 

 " setting " them, and of keeping the patient at rest, I shall con- 

 tent myself with describing the comparatively small number of 

 these accidents which may be successfully treated, under ordinary 

 circumstances. 



A fracture may occur straight across the bone ; obliquely ; or 

 longitudinally (lengthwise). 



The chief VARIETIES OF FRACTURES are as follows: — 



1. Simple fracture, when the bone is broken, without an ex- 

 ternal wound communicating with the seat of injury. As the 

 periosteum — the covering membrane of the bone — is generally 

 very strong in the horse ; it often keeps the broken surfaces 

 together, and thus prevents, for the time being, the fracture 

 becoming apparent. 



2. A comjjound fracture occurs when the broken bone commu- 

 nicates with an external wound. 



3. When the bone is broken in several pieces, the injury is 

 called a comminuted fracture. 



4. An impacted fracture takes place, when one broken end of 

 a bone is driven into the other broken end. 



Comminuted fracture and impacted fracture, may be either 

 simple or compound. 



COURSE OF UNION.— According to Erichsen the following are the 

 stages of the union of a broken bone. (1) The period of inflammation and 



