1010 



DISEASES OF THE HOCK. 



following anatomical facts: — Opposite the point of the calcis the 

 p< interior tibial 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 

 flexor perforans, 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. 



In neurectomy of the anterior tibial, the point selected is al the 

 externa] surface of the lower part of the leg, a hand's breadth above 



Figs. 540 and 541. — Neurectomy of the anterior tibial nerve. E A, Extensor pedis 

 muscle ; E L, tendinous portion of flexor metatarsi ; F M. muscular portion of 

 flexor metatarsi ; N. anterior tibial nerve ; V. anterior tibial vein ; A, anterior 

 tibial artery. (The operation should be performed a little nearer the hock than 

 indicated on Fig. 540.) 



the point of the hock. The anterior tibial nerve is situated on the 

 deep surface of the extensor pedis, between this muscle and the thin 

 muscular portion of the flexor metatarsi which separates it from 

 the anterior tibial artery, and from its large satellite vein — vessels 

 which lie directly on the anterior surface of the tibia, where they are 

 surrounded by a thick layer of connective tissue (see section, Fig. 538). 

 The method is as follows : — The point of operation being prepared, 

 the skin and subjacent aponeurosis are incised for a distance of 2i 

 to 3 inches, opposite the external margin of the extensor pedis muscle. 

 This muscle is separated first from the tendinous, then from the 

 muscular portion of the flexor metatarsi, on the anterior surface of 



