EXAMINATION OF HOOF FOR CORNS, ETC. 319 



by the use of the Immmer. The condition of the lateral 

 cartilages should be noted and the individual joints of the foot 

 tested by passive movement and by manipulation to detect new 

 growths or excessive sensitiveness. If, in spite of all this, no 

 satisfactory indication of disease is forthcoming, the liexor 

 tendons may be examined by running the thumb and fore- 

 finger along their course and noting any thickened or painful 

 spot. 



The causes are numerous and varied. They may be divided 

 into (1) congenital, (2) mechanical, (3) thermal, (4) chemical, 

 and (5) specific. The first three, however, are of chief import- 

 ance. Congenital causes are to be found in faulty conforma- 

 tion of the limb and irregularities in the condition of the hoof 

 causing unequal distribution of pressure. Mechanical causes 

 are numerous ; amongst them must be ranked, errors in trim- 

 ming the foot, weakening the hoof, bad fitting (causing local 

 pressure), dryness of the hoof, unskilful or excessive driving, 

 as well as direct wounds and bruises of the sensitive structures 

 of the hoof. Amongst thermal causes is burning of the toe 

 during fitting. Chemical and specific causes are rarer. The 

 fact that the corium lies between the hard horny box and the 

 equally hard os pedis explains the frequency with which it is 

 bruised and inflamed. 



The front feet (especially in their inner half) are more often 

 diseased than the hind. This results from the greater weight 

 they carry and the drying influences to which they are exposed. 

 In shoes with heels or heels and toes, one heel is apt to be 

 higher than the other, and as the foot is then raised unnaturally 

 high, any slight error in form or fitting is exaggerated, the 

 joints are strained, and the hoof itself sufiers. 



Treatment — The chief object is to remove the cause, per- 

 manently if possible. 



The shoe is carefully taken off, and its form, position, and 

 bearing surface examined. By replacing it for the moment we 

 note whether it fits at all points or not. The hoof is then 

 carefully examined in every part ; the white line especially 

 should receive attention. After removing a thin slice from the 

 white line and neighbouring parts the form and direction of 

 the nail holes can be seen. Any superfluous horn is then 

 removed from the wall and sole. The frog is cautiously 



