176 DISEASES AND THEIR TREATMENT. 



again, there is a disposition to have this disease from heredi- 

 tary causes. 



The coffin joint is composed of three bones : the os 

 pedis, the navicular and small pastern bones. The navicu- 

 lar bones answer the purpose of a sup- 

 port in allowing great elasticity of mo- 

 tion. The flexor tendon inserts itself 

 into the os pedis, and passes immediate- 

 ly over the navicular bone, so that at 

 each step the navicular bone is thrown 

 upon one part of the os pedis and small 

 pastern at the same time. It will be 

 seen that in all cases of lameness of this 

 joint, as well as in any other joint lame- 

 ness, that the cartilage of the bones is 

 inflamed, and as the disease progresses 

 Section of thn Parts En- ulceration takcs placc, and consequently 

 tering into the compo- ancholosis. It is almost Striving against 



sition of the Foot, and , , , , i • . ,i 



the Fetlock and Pas- hope to be able to cxplam to the gener- 



tern Joints. ^j reader the symptoms to enable ability 



a OS suffraginis b Os ^o locate the disease with any degree of 



coronae. c Os pedis, d ccrtamty. Corns or bruiscs of the sole, 



pe^foran^lnd perforJtus Contraction, or almost any cause exciting 



tendons, g Inferior sesa- inflammation in the foot, may cause simi- 



moideal ligament. h , , , , ,. -^ , 



Cleft of frog, i Side of lar lameucss, and to an ordinary observer 

 c?uV/Vonartsub- there cannot be that fine judgment 

 stance. necessary to trace from certain pecu- 



liarities the location of the trouble. 

 Horses having navicular disease invariably travel more on 

 the toe than on the heel, consequently the shoe is always 

 worn more at the toe than at the heel. The hoof rarely or 

 never is malformed, but the disease commonly occurs in 

 healthy looking feet, contraction of one or both heels, which 

 will in many cases interfere with the outer cartilage of the 

 joint. In the cases of long standing the frog appears to 

 recede, and does not have a natural appearance. If the 

 horse is taken suddenly lame, sometimes scarcely putting 

 the foot down, and only presses upon the toe, feel of the 

 foot carefully. If there is heat around the top of the hoof 

 and tenderness — even a little at the heel — there is probably 

 strain of the coffin joint. In incipent cases (first stages) 

 there is fever and tenderness to motion of the joint, which 



