BILATERAL DIGITAL NEUROTOMY 161 



.5. _ A small bottle of alcohol to dry the field and complete 

 the disinfection. 



6. A pan containing sterilized water or a clean solution 

 of mercuric chloride i : 2ooo, to be used by the assistant to 

 bail blood from the wound as the dissection proceeds. 



7. Bandages and cotton to temporarily protect the 

 wound on one leg as the other one is being Operated upon. 

 (Necessary only in table restraint.) 



8. Bandages and cotton to protect wounds permanently 

 when operation is complete. 



9. Scalpel, dissecting forcep, nerve elevator and needle 

 holder. 



10. Tray for the instruments. 



11. Needles threaded with sterilized silk, one for each 

 wound. 



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

 caine. 



TECHNIQUE. — The technique of the operation, begin- 

 ning after the horse has been secured and the leg brought 

 into the appropriate position, is as follows : 



First Step.— -Locating the Seat of Operation. — The line 

 of incision extends along the border of the tendon of the 

 flexor pedis perforans on the inferior aspect of the fetlock 

 joint. (Fig. 99.) The posterior digital nerve, the plantar 

 artery and the plantar vein are located superficially in the 

 groove intervening between the border of this tendon and 

 the posterior border of the os sufifraginus. -•.,'* These three 

 anatomical structures are grouped together in a sheath of 

 areolar tissue, the:; nerve occupying the posterior location 

 closely re'ated to the vein. The artery occupies the anterior 

 position in the group, located somewhat deeper than the 

 nerve and on the opposite side of the vein. Counting from 

 before backwards these structures are arranged as follows : 

 Artery, vein and nerve. 



Second Step. — Disinfection of the Field. — The hair is 

 clipped with the clippers or scissors, well lathered with soap 

 and water and then shaved over a surface one inch square. 

 The field thus shaved is well rinsed with water to rid it of 

 loosened hairs, washed for' some moments with the mercuric- 

 solution, 1-500, and then dried with alcohol. 



Third Step. — The Incision. — The incision is made 

 through the skin three-fourths of an inch long, at one stroke 

 if possible, made slowly and deliberately. The nerve can 

 often be elevated through a much shorter incision, but since 



