164 THE SURGICAL ANATOMY OF THE HORSE 



the operator should see the nerve before he picks it up. The deep fascia 

 ^hould next be seized with the forceps and incised in a vertical direction, 

 after the manner of incising the skin. This process is preferable to that 

 of dissecting out the fascia, since it does not disturb the relationship of 

 the underlying structures, and there is a much smaller cavity left to be 

 filled up during the healing process. 



The next step is to separate the edges of the superficial and deep 

 incisions, when the nerve should be distinctly seen by the operator. If 

 it is not seen it may be brought into view by the application of slight 

 pressure with the finger to the opposite side of the limb on the line of 

 the perforans tendon, the lips of the incision being kept open mean- 

 while. 



The nerve should now be carefully dissected from the surrounding 

 structures until it is quite free and its longitudinal striation is distinctly 

 evident, when it may be brought through the cutaneous wound by 

 means of the neurectomy needle. The nerve should be severed near the 

 upper extremity of the wound first, the distal severed and then seized 

 with the artery forceps, and in this manner an inch of the nerve should 

 be excised. The application of the forceps will prevent the nerve slipping 

 away from the operator, and enable him to pull the distal portion well 

 out and remove the necessary length of nerve. The wound should be 

 closed by inserting one or two simple interrupted sutures. 



In connection with the corresponding operation on the external 

 plantar nerve, care must be taken not to adopt a seat too high up the 

 limb, in order that the nerve may be severed at a lower level than the 

 spot where it is joined by the communicating branch from the internal 

 plantar nerve. 



Lastly, a little cotton wool with dry dressing should be applied to 

 the wounds, and the fetlock bandaged. 



A common complication is the formation of a neuroma on the 

 proximal end of the severed nerve. To dissect out this tumour is usually 

 a matter of considerable difficulty, since it is intimately associated with 



