398 



circular ritlges, developed most toward the heels, cover the upper part 

 of the hoof. When both feet are affected the animal points first one 

 foot then the other, and stands with the hind feet well forward beneath 

 the body so as to relieve the forefeet as much as possible from bearing 

 weight. In old cases the wasting of the muscles and the knuckling at 

 the fetlock become so great that the leg can not be straightened, and 

 locomotion can scarcely be i)erformed. The disease generally makes a 

 steady progress without inclining to recovery — the remission of symp- 

 toms in the earlier stages should not be interpreted as evidence that 

 the process has terminated. The complications usually seen are ring- 

 bones, sidebones, thrush, contracted heels, quarter cracks, and frac- 

 tures of the navicular, coronet, and i^astern bones. 



Treatment. — But few cases of navicular disease recover. In the 

 early stages the wall of the heels should be rasped away as directed in 

 the treatment for contracted heels, until the horn is quite thin; the 

 coronet should be well blistered with Spanish-fly ointment, and the 

 patient turned to grass in a damj) field or meadow. After three or four 

 weeks' time the blister should be repeated. This treatment is to be 

 continued for two or three months. Plane shoes are to be i)ut on when 

 the patient is returned to work. In chronic cases the animal should 

 be put to slow, easy work. To relieve the pain, neurotomy may be 

 performed — an operation in which the sense of feeling is destroyed in 

 the foot by cutting out pieces of the nerve at the fetlock. This opera- 

 tion in nowise cures the disease, and since it may be attended with 

 serious results can only be advised in certain favorable cases, to be de- 

 termined by the veterinarian. 



SIDEBONES. 



A sidebone consists in a transformation of the lateral cartilages found 

 on the wings of the coflin bone into bony matter by the deposition 

 of lime salts. The disease is a common one, especially in heavy horses 

 used for draft, in cavalry horses, cow-ponies, and other saddle horses, 

 and in runners and trotters. 



Sidebones are peculiar to the fore feet, yet they occasionally develop 

 in the hind feet where they are of little importance, since they cause 

 no lameness. In many instances sidebones are of slow growth, and 

 being unaccompanied by acute inflammation, they cause no lameness 

 until such time as, by reason of their size, they interfere with the action 

 of the joint. (Plate xxxii. Fig. 4.) 



Causes. — Sidebones often grow in heavy horses without any apparent 

 injury, and their development has been attributed to theoverexpansion 

 of the cartilages caused by the great weight of the animal. Blows, and 

 other injuries to the cartilages, may set up an inflammatory process 

 which ends in the formation of these bony growths. High-heeled shoes, 

 high calks, and long feet are always classed among the conditions which 

 may excite the growth of sidebones. They are often seen in connec- 



