CHAPTER XIT. 



DISEASES OF THE FEET. 



ft. ULCKRATION OP THE FOOT (NAVICULAR DISEASE). II. CRACKED HOOFS. IH. HOOV 



KOT. IV. CORNS. V. CONTRACTION OF THE HOOP (NARROW HEEL). VI. INJU- 

 RIES TO THE PROG. ^VII. FOUNDER. VIU. NAIL PRICKING. IX. CANKER. X. 



SAND CRACK. XI. FALSE QUARTER. XII. QUITTOR. XIU. TOE CRACK. XIV. 



PUMICE FOOT. XV. SEEDY TOE. XVI. OSSIFIED CARTILAGES. XVII. SIDE BONES. 



"'■~— XVUI. INCISED AND PUNCTURED WOUNDS OF THE SOLE. 



I. Ulceration of the Foot— (Navicular Disease). 



Between the coffin bone and lower pastern there is a small bone which 

 forms the projection of the heel and rests upon the frog of the foot. 

 This bone is called the shuttle or navicular bone. The inflammation of 

 the surface of this bone is called the navicular disease. It may implicate 

 the sjrnovial sac, the ligaments and the flexor tendon which plays over it. 

 ( )ne of the uses of the navicular bone is to give increased strehgth to the 

 connection between the coffin bone and the joint above. Another use is 

 to enable the flexor tendon, which passes over it and is joined to the 

 coffin bone, to give increased pliability, strength and motion to the foot. 

 In high bred horses, and all those used for fast work, this bone i» 

 peculiarly liable to injury and consequently to disease. This disease is 

 inflammation and subsequent ulceration of this highly organized bone. 

 The difficulty may extend to the interior of the bone , to the tendon which 

 passes over its surface and even involve the adjacent parts. 



Causes- — It is thought that a rheumatic constitution predisposes an 

 animal to this disease. Certain it is that highly organized and weak 

 limbed animals most usually suffer from it, probably from the fact that 

 they are not able to withstand an injury that a stronger limbed animal 

 would do, especially when carrying a bad fitting shoe, or subject lo 

 Tiolent exertion or over strain of any kind. Other causes than bad shoes 

 29 461 



