CALCANEO-METATARSAL LIGAMENT— CURB 



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in those cases in which the tuber calcis is very long, for the summit of 

 the latter is the point at which the power is applied. In such hocks, 

 therefore, there is greater strain upon the calcaneo-metatarsal ligament 

 during extension of the joint, and consequently a greater predisposition 

 to the formation of curb. Hocks which are " tied in below " are also 

 said to be very liable to curb formation. Conformation has thus a very 

 important bearing on this affection, a point which should be borne in 

 mind when selecting sires and dams for breeding purposes. 



In many cases of curb the swelling appears suddenly as a result of 

 severe sprain of the ligament, with occasionally laceration of some of its 

 fibres. In these cases the swelling is diffused, and is hot and painful to 

 the touch. The animal is lame, the degree of lameness being in pro- 

 portion to the severity of the injury. In such cases diagnosis presents 

 little difficulty. In other cases the swelling forms slowly, and is commonly 

 in the form of a small nodular enlargement, which appears near the 

 attachment of the calcaneo-metatarsal ligament to the cuboid. Such 

 cases are more difficult to detect, and care must be taken not to confuse 

 them with an abnormally large head of the external metatarsal bone. 

 Both are quite hard. In many cases the former appears quite as hard 

 as bone. To distinguish between them the observer should stand at the 

 side of the patient, when he will be able to see whether or not the 

 enlargement is along the course of the ligament. Diagnosis should be 

 confirmed by palpation. Assuming that the left hock is being examined, 

 the observer should stand on the left side of the animal with his back 

 directed towards the horse's head. The palmar aspect of the middle 

 finger should then be passed along the course of the ligament, the tip 

 of the finger being directed downwards. In this manner a very slight 

 convexity may be discovered without difficulty. 



Should there be lamenesss in the chronic forms of curb in which the 

 enlargement is cold and hard, it will be found that the interference with 

 the action of the joint is by no means in proportion to the size of the 

 enlargement. 



