158 THE SURGICAL ANATOMY OF THE HORSE 



of infrequent occurrence, it is practically impossible to perform the 

 operation again higher up the limb. A further objection is that the 

 nerve is usually severed above the origin of the branches distributed to 

 the liexor muscles. 



A second seat, which was adopted later, was quite clear of the pectoral 

 muscle, namely, some three and a half to four inches down the shaft of the 

 radius. In this case there should be very little haemorrhage (only from 

 cutaneous vessels), but the nerve is here placed at the back of the radius, 

 and but a short distance to the inner side of the middle line of the limb. 

 A great difficulty is thus met with, on account of the leverage which is 

 necessary to bring the nerve through the cutaneous opening. Another 

 difficulty is that the nerve cannot be seen by the operator, even upon 

 widely separating the lips of the incision. The operator has therefore 

 solely to rely upon his sense of touch. 



After the examination of a large number of limbs, the author has 

 come to the conclusion that the best seat of operation in median 

 neurectomy is obtained as follows, and the advantages of this seat over 

 those named will be pointed out. This seat is obtained by making an 

 incision a quarter of an inch behind the edge of the radius felt;^ The 

 length of the incision should include half an inch of the inferior edge of 

 the pectoral muscle, and it should then be extended in the downward 

 direction for another half an inch. (Slight modification of these 

 instructions is occasionally necessary on account of variation in 

 the direction taken by the internal subcutaneous vein ot the fore- 

 arm. The course of the vein, however, is distinctly indicated by the 

 elevation which it forms on the exterior of the limb, and the 

 operator will have no difficulty in avoiding it.) The muscle in this 

 region is extremely thin, and consequently very little haemorrhage occurs 

 by incising it. 



The following structures should be cut through in turn. Firstly, 

 the skin, which should be made tense by stretching with the thumb and 

 medius finger of the left hand, thus enabling the operator to make a clean- 



