112 NEUROTOMY. 



duing the increased sensibility of the part, by diminishing the proportion of nervous 

 influence distributed on the foot. He laid bare one of the metacarpal nerves, and 

 divided it -with a pair of scissors. There was always an immediate and decided 

 diminution of the lameness, and, sometimes, the horse rose perfectly sound. This 

 happy result, however, was not always permanent, for the lameness returned after 

 the lapse of a few weeks, or on nmch active exertion. He next cut out a small piece 

 of the nerve. The freedom from lameness was of longer duration, but it eventually 

 returned. 



He then tried a bolder experiment. He excised a portion of the nerves going both 

 to the inner and outer metacarpals. We transcribe his own account of the result of 

 the first case of complete neurotomy — excision of the nerve on both sides of the leg — 

 that ever was performed. 



" The animal, on rising, trotted boldly and without lameness, but now and then 

 stumbled with the foot operated on. l"he wounds healed in a few days, and the 

 patient was put to grass. Some weeks afterwards a favourable account was received 

 of her soundness ; but she was soon brought again to us, on account of a large sore 

 on the bottom of the foot operated on, and extending from the point of the frog to the 

 middle and back part of the pastern. The mare, in galloping over some broken glass 

 bottles, had placed her foot upon a fragment of the bottom of one of them, and which 

 had cut its way through the frog and tendon into the joint, and stuck fast in the joint 

 for some seconds, while the animal continued its course apparently n^frardless of 

 injury. The wound bled profusely, hut the mare was not lame. I\iany days had 

 elapsed before I saw her, and large masses of loose flesh were cut from the edges of 

 the wound, without the animal showing the slightest sign cf sufi'cring pain. The 

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

 in sores of parts not deprived of sensibility. Such extensive injury, however, had 

 been done to the joint as rendered the preservation of free motion in it very impro- 

 bable, even were the opening to close, which was a matter of doubt, and therefore 

 she was destroyed. It appeared clearly IVcm this, that by ike destruction <j' sensibility 

 the repairing powers of the part were not injured; but that the natural guard against 

 injury being taken av.-ay 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 cut in the next ])v;ge gives a viev.' of the nerve on the inside cf 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 cf the foot and supply it with feeling. The continuation 

 of the nerve below the fetlock is given principally to the quarters and hinder part of 

 the foot. The grand consideration, 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 fcrt, 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 horse- 

 man so much dislikes ] 



The horse must be cast and secured, and the limb to be operated on removed from 

 tne hobbles and extended — the hair having hern previously shaved from the part. 

 The operator then feels for the tlirol)bing 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 be 

 distinguished from thorn by its lying behind the others, and by its whiteness. A 

 crooked needle, armed witli silk, is then passed under it, in order to raise it a little. 

 It is dissected from the cellular substance beneath, and aliout three quarters of an inch 

 of it cut out, — the first incision bein^r made at the upper part, in which case the second 

 incision will not be felt. The horse must then be turned, and the operation per- 

 formed on the other side; for there is a nervous tnink on both sides. The wounds 

 are now closed with strips of adhesive plaster, a bandage placed over them, the head 

 tied up for a couple of days, and the animal kept rather low, and as quiet as ])os- 

 sible. The incisions will generally rapidly heal ; and in three weeks or a montl), 

 and sometimes earlier, the horse will be fit for work. 



* Veterinarian, vol. ix. p. 363. 



