DISEASES OF HORSES 243 



SPRUNG KNEES. 



Though not positively the result of diseases of the tendons act- 

 ing upon the knees, we venture to consider this deformity in con- 

 nection with that which we have just described. It consists in such 

 an alteration in the direction and articulation of the bones which 

 form the various carpal joints that instead of forming a vertical line 

 from the lower end of the forearm to the canon bone they are so 

 united that the knee is more or less bent forward, presenting a con- 

 dition due to the retraction of two of the principal muscles by which 

 the canon bone is flexed. 



Cause. This flexion of the knee may be a congenital deform- 

 ity and have continued from the foaling of the animal ; or, like club- 

 foot, it may be the result of heavy labor which the animal has been 

 compelled to perform at too early an age. It may also be due to 

 other diseases existing in parts below the kneejoint. 



Symptoms. This change of direction largely influences the 

 movement of the animal by detracting from its firmness and prac- 

 tically weakening the entire frame, even to the extent of rendering 

 him insecure on his feet and liable to fall. This condition of weak- 

 ness is sometimes so pronounced that he is exposed to fall even 

 when standing at rest and unmolested, the knees being unable even 

 to bear the portion of the mere weight of the frame which belongs 

 to them. This results in another trouble that of being unable to 

 keep permanently upright. He is apt to fall on his knees, and by 

 this act becomes presently a sufferer from the lesion known by the 

 term of broken knees. 



Treatment. Whatever may be the originating cause of this 

 imperfection, it detracts very largely from the usefulness and value 

 of a horse, disqualifying him for ordinary labor and wholly unfit- 

 ing him for service under the saddle without jeopardizing the safety 

 of his rider. If, however, the trouble is known from the start, and 

 is not the result of congenital deformity or weakness of the knee- 

 joint, or secondary to other diseases, Test, with fortifying frictions, 

 may sometimes aid in strengthening the joints; and the application 

 of blisters on the posterior part of the knee, from a short distance 

 above to a point a little below the joint, may be followed by some 

 satisfactory results ; but with this trouble, as with knuckling fetlocks, 

 the danger of relapse must be kept in mind as a contingency always 

 liable to occur. 



CURB. 



This lesion is the bulging backward of the posterior part of the 

 hock, where in the normal state there should be a straight line, ex- 

 tending from the upper end of the point of the hock down to the 

 fetlock. 



Cause. The cause may be a sprain of the tendon which passes 

 on the posterior part of the hock, or of one of its sheaths, or of the 

 strong ligament situated on the posterior border of the os calcis. 

 Hocks of a certain conformation seem to possess a greater liability 

 to curb than others. They are overbent, coarse, and thick in appear- 

 ance, or may be too narrow from front to back across the lower por- 



