172 VETERINARY SURGICAL OPERATIONS 



re-fixed with straps that will prevent any movement. 



EQUIPMENT, necessary to perform the operation of 

 median neurotomy : 



i. Securing apparatus. 



2. A pan of water containing soap, razor and sponge. 



3. A pan containing mercuric chloride solution, 1-1000. 



4. A tray for the instruments. 



5. One needle armed with silk enough for two stitches. 



6. Scalpel, small probe-pointed bistoury, nerve elevator, 

 dissecting forceps, and artery forceps. 



7. A pair of wound retractors (useful but not always 

 essential). 



8. Hypodermic syringe and 5 per cent solution of co- 

 caine hydrochlorate. 



9. Cotton pledgets for bailing and washing. 

 TECHNIQUE. — After the subject is cast and the leg 



brought to the appropriate position already described, the 

 technique is as follows : 



First Step. — Locating the Seat of Operation. — Median 

 neurotomy is performed over the internal radial tuberosity, 

 the level of which is brought prominently into the fore- 

 ground by securing the leg in the proper position. This 

 bony protruberance is easily located by palpation. If the 

 finger tips are pressed into the groove between the internal 

 border of the radius and the flexor muscles, and gradually 

 slid upward with firm pressure, a hard, rounded, obstacle will 

 be encountered as they approach the level of articulation. 

 This is the radial tuberosity, over which the median nerve 

 passes rather superficially, and upon which it can be felt by 

 lateral movements of the finger tips. The exact seat of in • 

 cision is a line passing vertically over the radial tuberosity, 

 exactly parallel to the internal border of the radius, but 

 about one-half an inch behind it. 



Second Step.— Disinfecting and Anaesthetizing the Field. 

 — The region is washed, shaved, well rinsed with mercuric 

 chloride solution, and then anaesthetized with subcutaneous 

 injections of cocaine. 



Third Step. — The Incision.— The skin is tensed with the 

 first and second fingers of the left hand, care being taken 

 not to disturb its normal relations. The skin here is so 

 loosely arranged ,that it is very 'liable to be carried in one 

 direction or other while tensing it, and thus leave the in- 

 cision some distance from the desired location when the ten- 

 sion is removed. The incision through the skin is then made 

 with the scalpel by one firm stroke from above downward. 



