76 



CLINICAL VETERINARY MEDICINE AND SURGERY. 



In a number of cases where the swelhng is old, large, diffuse, and 

 especially when it extends far forwards towards the bend of the hock, 

 firing, even if repeated, and section of the terminal branch of the flexor 

 metatarsi tendon fail, or only yield a very modified success ; lame- 

 ness persists or is remittent, being less marked after a certain amount 

 of exercise than on leaving the stable, though sometimes it is equally 

 pronounced before and after exercise : in these rebellious cases double 

 neurotomy of the sciatic and anterior tibial nerve, a deep branch of the 

 external popliteal sciatic, has been recommended. This treatment of 

 obstinate spavin by neurectomy is based on the following anatomical 



Fig. 8. 



P"lG, 9. 



Figs. 8 and 9. — Neurotomy of the anterior tibial nerve. E A, anterior extensor of the 

 phalanges. E L, lateral extensor. F M, muscular portion of the flexor metatarsi. 

 N, tibial nerve. V, tibial vein. A, tibial artery. (The operation should be performed 

 a little nearer the hock than indicated on Fig. 8.) 



facts : — Opposite the point of the calcis the great sciatic nerve divides 

 into two parts, the internal and external plantar nerves. Behind the 

 hock-joint the external plantar nerve gives off a fairly large branch, 

 which passes under the tendon of the deep flexor of the phalanges, and 

 detaches several twigs, of which some ramify over the surface of the 

 joint, whilst others penetrate into it. In front of the lower extremity 

 of the tibia the tibial nerve gives off several branches, which enter the 

 joint. 



Neurectomy of the great sciatic is made a hand's breadth above the 

 point of the hock. Ycm know the technique. 



