36 THE SURGICAL ANATOMY OF THE HORSE 



from the skin by a thick layer of dense fascia. The tendon is placed at 

 the back of the hock, as will be readily understood from Plate IX. 



In front of the tendon is a thick and powerful ligament, to which 

 the anterior face of the tendon is intimately related and which extends 

 for some distance round to the outer aspect of the joint. This is the 

 calcaneo-metatarsal ligament, which runs from the back of the tuber 

 calcis down the whole length of the back of the cuboid to be attached 

 inferiorly to the head of the outer small metatarsal bone. This ligament 

 is implicated in curb. On the superficial aspect of the ligament, and 

 towards the outer side of the joint, is the external saphena nerve. 

 This nerve, however, may frequently be found running further forwards 

 and clear of the ligament. A little more anteriorly, and also slightly 

 more superficially, is a cutaneous branch of the musculo-cutaneous 

 nerve which, in turn, is one of the terminal divisions of the external 

 popliteal. 



A large bone is seen in section, the major portion of which is placed 

 to the left of the middle line. In outline it appears somewhat reniform, 

 and to its posterior surface the calcaneo-metatarsal ligament is attached. 

 It will be readily gathered, from what we have said, that this bone is 

 the cuboid. On the outer aspect of the cuboid will be observed the 

 external lateral ligament of the joint. 



At the back of the joint there will be seen in the Plate, to the right 

 of the middle line and in line with the calcaneo-metatarsal ligament, 

 another tendon. This is the tendon of the flexor perforans. In section 

 it is elliptical the long axis of the ellipse being directed transversely. 



Two nerves are seen, one on either edge of the tendon just mentioned. 

 These are the outer and inner plantar nerves, into which the posterior 

 tibial nerve divides just above the hock, and which then pass through 

 the tarsal sheath with the perforans tendon. In front of each nerve is 

 the corresponding artery, whilst in front of the external plantar artery is 

 tlie external metatarsal vein. 



Running from the back of the cuboid transversely, in front of the 



