470 



XHUROTOMV. 



the mare was not lame. Many days had elapsed hefore I saw her, and 

 laro'e masses of loose flesh were cut from the edges of the wound without 

 the animal showing the slightest sign of suffering pain. The processes 

 usually attending sores went on, with the same appearances, that took place 

 in soi'es of parts not deprived of sensibility. Such extensive injury, how- 

 ever, had been done to the joint, as rendered the preservation of free mo- 

 tion in it very improbable, even were the opening to close, which was a 

 matter of doubt, and therefore she was destroyed. It appeared clearly 

 from this, that by the destrtcction of sensibilitij the repairing powers of the 

 parts were not injured ; but that the natural guard against injury being 

 taken away by the division of both the nerves, an accident was rendered 

 destructive, which, in the usual condition of the foot, might have been less 

 injurious.' 



The folio \ving cut gives a view of the nerve on the inside of the leg, as 

 it approaches the fetlock. It will be seen that branches are given off 

 above the fetlock, which go to the fore part of the foot and supply it with 

 feelino-. The continuation of the nerve below the fetlock is given princi- 

 pally to the quarters and hinder part of the foot. The gi-and considera- 

 tion, then, with the operator is — does he wish to deprive the whole of the 

 foot of sensation, or is the cause of lameness principally in the hinder part 

 of the foot, so that he can leave some degree of feeling in the fore part, 

 and prevent that alteration in the tread and going of the horse which 

 the hoi'seman so dislikes ? 



A The metacarpal nerve on the inside of the oflf leg at the edge 

 of the shank bone, and behind the vein and artery. 



B The continuation of the same nerve on the pastern, and pro- 

 ceeding downward to supply the back part of the foot 

 with feeling. 



C The division of the nerve on the fetlock joint. 



I) The branch which suppilies with feeling the fore part of the 

 foot. 



E The artery between the vein and nerve. 



F The continuation of the artery on the pastern, close to, and 

 before the nerve. 



G The vein before the artery and nerve. 



H The same vein spreading over the pastern. 



I One of the flexor tendons, the pcrforntus (perforated). 



J The deeper flexor tendon, the perforans (perforating, con- 

 tained within the other). 



K The tendinous band in which the flexors work. 



L One of the extensors of the foot. 



M The internal or sensitive frog. 



N The posterior lateral ligament. 



The flesliy or sensitive laminse covering the coffin-bone, the 

 horny crust being removed. 



P The horny crust. 



Q The sole. 



The horse mitst be cast and secured, and the limb to be operated on 

 removed from the hobbles and extended — the hair having been previously 

 shaved from the part. The operator then feels for the throbbing of the 

 artery, or the round firm body of the nerve itself, on the side of the shank 

 bone or the larger pastern. The vein, artery, and nerve here run close 

 together, the vein nearest to the front of the leg, then the artery, and the 

 nerve behind. He cautiously cuts through the skin for an inch and a half 

 in length. The vessels will then be brought into view, and the nerve will 



