Special Injuries of Bones, Joints and Muscles. 345 



bony. The process in the early stages often appears to 

 consist in the dragging of the periosteum and vessels from 

 the surface and the development of bone beneath. But as 

 the disease advances the whole surface of one or both 

 bones may become involved, leading to a general deposi- 

 tion of new bony matter, extending, it may be, over tlie 

 joint between the two pastern bones, or between the lower 

 pastern and the bone of the foot, and abolishing all move- 

 ment. Eingbones may also take origin in partial fract- 

 ures, in concussion, in rheumatoid disease, and in faults 

 of nutrition, in which the earthy salts are largely passed 

 with the urine. 



Sijmptoms. Lameness may be almost altogether absent, 

 or it may be extreme in such cases as are attended by act- 

 ive inflammation of the bone or joint, or when the joint 

 has become fixed by bony deposit. The heel may be first 

 brought to the ground or, in the hind foot, the fetlock 

 may knuckle over and the toe strikes first. The lameness 

 is worst on hard ground and usually increases with exer- 

 cise. Swelling may be scarcely perceptible and confined 

 to the inner or outer side of one pastern bone, or it may \ 

 be an extreme enlargement of the whole pastern region. 

 It may be hard throughout m old cases, or softer and 

 slightly elastic at points where active disease is still going 

 on. Forcible bending of the pastern causes much pain, 

 as also pressure on the swelling and especially on the 

 softer and more recent deposits. 



Treatment. Eest, second the indicatious of nature in 

 order to secure an easy position, using a high-heeled shoe 

 when the animal walks on the toe and a thin-heeled one 

 when he walks on his heel. If there is very active in- 

 flammation adopt soothing measures fii'st and then blister 

 severely or even fire. Corrosive sublimate and camphoi! 

 20 grains of each, muriatic acid 10 drops and oil of tur 

 pontine 1 oz. is often useful in such cases, but should be 

 watched and washed ofl' when sufficient exudation has 

 taken place, otherwise it maj- blemish. In firing it is usu- 



