214 DISEASES OF THE HORSE'S FOOT 



has discovered, immediately after he has done it, that he 

 has pricked the animal. He has then withdrawn the nail, 

 and either sent the animal back with that nail altogether 

 missing from the set in the shoe, or with the hole filled up 

 with a stump. 



The shoe once off, the hole made by the nail in the 

 horn should be minutely examined for the presence of 

 hemorrhage, inflammatory fluid, or pus exuding from 

 them, and also for evidence of their correct placing in the 

 foot. Should fluid matter issue from any one of them, or 

 should it be deemed that one has approached too near the 

 inner margin of the white line, more especially if tender- 

 ness exists around it, that hole should be followed up 

 with a ' searcher ' or small drawing-knife until diagnosis is 

 certain. 



Complications. — Before proceeding to discuss the com- 

 plications that may arise in the case of pricked foot, we 

 may call to mind that the anatomy of the parts teaches us 

 that the most serious position in which a punctured wound 

 can occur is at the center of the foot. Here the plantar 

 aponeurosis, the navicular bursa, the navicular bone itself, 

 or the pedal articulation may be injured. 



Anterior to this position the most serious mischief that 

 c^n ordinarily result is stabbing of the os pedis. 



Posterior to the position we have named, the only struc- 

 ture to be injured is the plantar cushion. 



Anatomically, then, the inferior surface of the foot may 

 be divided into three zones, as follows : 



A. Anterior, extending from the toe to the point of the 

 frog. 



B. Middle, extending from the point of the frog to the 

 commencement of its median lacuna. 



C. Posterior, including everything posterior to the mid- 

 dle zone. 



This division of the inferior surface of the foot into 

 zones will be somewhat of a guide also when describing 

 the complications next to follow : 



(a) Suppuration. — This is the common complication of 



