Journal of Ai;r/ciilf//n\ 



[9 Sept., 1907. 



Causes. — As with spavin, curb occurs most frequently in horses with 

 defectively formed hocks. The formation most fertile in inducing curb 

 is that in which the point of the hock (the summit of the calcaneum bone, 

 corresponding to the heel-bone of man) is largely developed, while the 

 hock is narrow or " tied in" at the lower part. In such hocks, the 

 muscles attached to the point of the hock, under the influence of great or 

 sudden exertion, cause such a strain to be put upon the calcaneo-cuboid 

 ligament as to severelv sprain it or tear it partially from its lower attach- 

 ment. It is under such circumstances as springing out of boggv or holding 

 ground on the " take-off " side of a jump or when drawing heavy loads 

 uphill that the strain inducing curb most often occurs. Cuibs seen in 

 young unbroken horses are the result of sprains sustained while " at play " 

 in the paddock or in jumping. 



Fig. 99. No curb. (After Hayes. 



100. Curb. (After Hayes.) 



The term "curby hocks " as implying a condition of soundness with 

 the shape of curb is a misnomer ; there is either a curb or there is none. 

 If by the term is meant a shape of hock predisposed to curb (as, for 

 instance, " sickle hocks ") it may be admissible. 



Symptoms. — In most cases the enlargement is evident from the first, 

 and may be most distinctly seen when standing at right angles to the horse, 

 the straight and perpendicular line from the point of the hock to the fetlock 

 showing a bulge at the seat of curb. Old standing curbs seldom cause 

 lameness, the parts having been strengthened by the swelling they have 

 undergone, but newly-sprung curbs often cause great lameness. In such 



