DISEASES OF THE BONES 401 



was slight evidence of navicular disease. The articular 

 cartilage of the corono-pedal Joint had been almost com- 

 pletely removed, and there was sclerosis of the opposed 

 bony surfaces, which by unequal wear had brought about 

 deformity of the os coronas and os pedis. 



There was very old-standing fracture of the pyramidal 

 process (see Fig. 157), with the formation of a false joint 

 between the process and the pedal bone. There was also a 

 recent fracture of the part of the pedal bone which carries 

 the articulation for the navicular bone, and this and the 

 tendon lesions probably accounted for the final symptoms 

 of 'break- down.' 



Neurectomy enabled us to get a year's useful work out 

 of what would otherwise have been a hopeless cripple.^ 



C. FRACTURES OF THE BONES. 



More or less by reason of the protection afforded them by 

 the hoof fractures of the bones of the foot are rare. When 

 occurring they are more often than not the result of direct 

 injury, as, for example, violent blows, the trapping of the 

 foot in railway points, the running over of the foot with 

 a heavily-laden waggon, or violent kicking against a gate or 

 a wall. They occur also as a result of an uneven step upon 

 a loose stone when going at a fast pace, and as a result of 

 sudden slips and turns, in which latter case they are met 

 with when animals have been galloping unrestrained in a 

 field, or when an animal, ridden or driven at a fast pace, is 

 suddenly pulled up, or just as suddenly turned. 



At other times fractures in this region take place without 

 ascertainable cause, and cases are on record where animals 

 turned overnight into a loose box in their usual sound 

 condition have been found in the morning excessively lame, 

 and fracture afterwards diagnosed. 



* A. R. Routledge, M.R.C.V.S., Journal of Comjjarative Patliology 

 and Therapeutics, vol. xvi., p. 371. 



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