OyO OPERATIONS OX THE FOOT. 



and fetlock. If the heels are pared off, in such a manner that the 

 frog- is well prominent, and the horse becomes much heated, the 

 lameness is increased, although at first it may have been very 

 slight. Blacksmiths may frequently obtain the same result by 

 placing under the foot a bar shoe, which, then resting on the frog, 

 and not the heels, greatly aggravates the lameness until it be- 

 comes excessive. This mode of diagnosis was originally indicated 

 by Brauell : When, after more or less exercise, the animal is left 

 to cool off, he at once points, straightens his fetlock, and slightly 

 flexes the knee; the leg has a trembling motion, and no rest is 

 taken upon the heels. 



There are, however, according to Hertwig, cases where navicu- 

 lar disease suddenly reaches a period where, in the stable, the 

 animal avoids all resting on the heel ; points constantly, and hes- 

 itates to put his foot on the ground when made to walk. It al- 

 ways seems that there must be some traumatic lesion in the foot, 

 as a punctured wound or a suppurating corn ; and still there is 

 no increased heat in the hoof, and no extraordinary x^ulsation of 

 the arteries of the foot. 



The disease has a tendency to increase, and the animal soon 

 becomes very lame upon being put to work, especially on a hard 

 road or rough ground. The heat of the foot is increased princi- 

 pally after work, though not in proj)ortion to the lameness. The 

 sensibility of the foot is also more manifest under the exploring 

 pressure of the nippers. In the stable the pointing is well 

 marked, and the trembhng of the leg gives signs of deep and per- 

 sistent pain. It is only after several months of this suffering that 

 the foot begins gradually to show a change of shape. It then be- 

 comes visibly narrowed and elongated, in a manner which can 

 readily be detected both by sight and management. There is a 

 general atrophy of the hoof; the periople has disappeared, or 

 scales off; the foot becomes covered with ridges, more or less 

 marked, but better developed toward the heels ; the frog has be- 

 become sunken and atrophied; the sole is ecchymosed, present- 

 ing evidences of corns ; and the leg is atrophied, esj)ecially about 

 the muscles of the shoulder. 



In cases where both fore feet are affected, the animal points 

 with either foot alternately, while seeking the desired relief for 

 each, but the rest on either is very short. The hind legs are 

 brought under the centre of gravity, the back is arched, and the 



