190 THE PRACTICE OF VETERINARY MEDICINE. 



Fracture of the astragalus sometimes occurs. It may be 

 caused in various ways, as by kicks, etc. If the fracture 

 extends into the hock-joint, the case is hopeless. 



Os Calcis. — Fracture of the os calcis is usually caused by 

 direct injury, or violent muscular contraction. Sei)aration 

 of the fractured ends of the bone may, or may not 

 occur. 



Symjifoms. — Crepitus may be present in some cases, 

 absent in others. There is well-marked lameness, and the 

 animal manifests considerable pain. Swelling is present in 

 a greater or less degree. In most cases a large quantity of 

 ossific material is thrown out, and an abnormal enlargement 

 is the result. 



Treatment. — Place the patient in slings ; apply plaster of 

 Paris, or starch bandages, etc. In many cases it is better 

 not to apply bandages, that is, in such cases as they cannot 

 be kept in j^osition, and consequently irritate the imtient. 

 In case complete separation of the fractured ends of the 

 bone takes place, it is, as a rule, advisable to have the 

 animal destroyed. 



Metatarsal Bones. — Fracture of these bones is usually 

 produced by direct injury, in some cases the external wound 

 being of a very trivial nature indeed. In all long bones 

 there are three centres of ossification — one for the shaft 

 known as the diaphysis, and one for each of the extremities 

 known as the epiphj^ses. The parts sometimes separate in 

 young animals. The treatment is to keep the animal quiet, 

 and allow plenty of time for the separated poi'tions to 

 reunite. 



Inferior Maxilla. — Falling may fracture either the inferior 

 or pre-maxilla, or it ma}^ be fractured by getting a hook in 

 it and pulling back, and it may sustain a fracture — rarely, 

 however— during the operation of extracting teeth. If the 

 anterior maxillary bone sustains a fracture by, say, a hook, 



