go CLINICAL VETERINARY MEDICINE AND SURGERY. 



atrophied. On vertical section of the hoof, the articular synovial 

 membranes and the small sesamoid (navicular) sheath appeared in- 

 flamed, injected, and infiltrated ; the synovia was scanty and reddish 

 in colour. The navicular bone showed signs of rarefying ostitis ; its 

 lower surface was denuded of cartilage, its compact tissue was under- 

 going exfoliation, and its cancellous tissue was hyperaemic and friable. 



Softening and rupture of the flexor tendons may always follow 

 plantar neurectomy, but are commonest when the operation has been 

 performed for navicular disease, appearing due in part to extension of 

 the disease, in part to trophic changes produced by the operation. 

 Among French authors, Renault, Beugnot, and Rabouille were the first 

 to note this. In two cases operated on by Rabouille, rupture of the 

 tendons ended in the fetlock and the bulbs of the heel coming in con- 

 tact with the ground, the digit from the fetlock downwards lying 

 horizontally. In both cases the tendons showed trophic changes in 

 the phalangeal region, and the perforans was completely ruptured close 

 to its insertion into the pedal bone. Bouley, Goubaux, MM. Jacoulet, 

 Mollereau, and many others have seen similar cases, but, I repeat, these 

 lesions occur where neurectomy has been performed for navicular 

 disease, and if the operation has favoured their development it is not 

 entirely responsible for their occurrence. 



The course taken by injuries affecting a neurectomised foot varies. 

 Bouley states that under the influence of the cerebro-spinal system, 

 "healing inflammation" proceeds normally in the parts affected by 

 neurectomy. This, however, is not always the case. You recently 

 saw a horse, unnerved for a large external sidebone, afterwards develop 

 a quittor on the inner surface. In treating the quittor the lateral 

 cartilage was removed, and the subsequent traumatic inflammation 

 showed very special characters. The wound became indolent and 

 healed very slowly, while the coronet and pastern increased enormously 

 in size ; severe lameness continued, and the animal became useless. 



The cases I have just mentioned, together with others published 

 abroad and certain collected by human surgeons, show that if removal 

 of nervous influence does not produce immediate and evident effects on 

 the phenomena of nutrition, it may, in combination with other causes, 

 like wounds, infections, etc., produce lesions of rapid or slow develop- 

 ment, and of inflammatory, gangrenous, hypertrophic, or atrophic nature. 

 No organ or tissue, in the region served by the divided nerve, is safe 

 from these changes. They appear especially to affect the skin, 



