GELATINOUS DEGENERATION. 355 



In the dissection of the foot from which the figure was drawn, 

 the navicular bone was fractured, and the inferior broad liga- 

 ment ruptured. Neither of these results was due to violence, 

 for the animal had been at rest for several weeks prior to its 

 death, and the various changes had come on gradually. 



Another unfavourable result of the operation is loss of the 

 hoof from suppuration induced by accidental injuries to the foot, 

 or from morbid action in the tissues, deprived of their nervous 

 sensibility. 



In some cases regeneration of the nerve substance occurs ; the 

 divided ends become continuous by growth from their extremi- 

 ties, the nervous current is re-established, and the lameness 

 recurs. These results, however, do not take place for at least 

 two years after the operation is performed. If the lameness is 

 severe, it may be necessary to excise the reunited nerves, and 

 thus again destroy the sentient communication between the 

 diseased part and the nervous centres. It has been already 

 shown that fracture of the navicular bone, when unaccompanied 

 by degenerative disease of the bursa and tendon, may not inter- 

 fere with the animal's usefulness ; the fractures, as in Figs. 15 

 and 16, being united by a false joint, and the animal continuing 

 to perform his daily task with apparent ease and comfort. 



My experience leads me to the conclusion that the lameness 

 arising from ring-bones or side-bones, when the feet are good 

 and strong, is generally permanently benefited by neurotomy, 

 the animal restored to its full usefulness, and remaining sound 

 for many years. Indeed, in ring-bone lameness I have repeatedly 

 noticed that not only has the lameness been entirely cured, but 

 that there has been a gradual absorption of the osseous new 

 formation, and a restoration of the pastern almost to its natural 

 shape and dimensions. When the operation has been performed 

 for the relief of these lamenesses, there appears to be an absence 

 of any tendency to gelatinous degeneration or other alteration of 

 structure. 



