DISEASES OF THE HOESE. 349 



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. 



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

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

 ing 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 caJcis. 



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 ma}'^ be too narrow from front to back across the lower por- 

 tion. This condition may therefore result as a sequence to congeni- 

 tal malformation, as in the case of horses that are saber-legged. It 

 often occurs, also, as the result of violent etforts, of heavy pulling, of 

 high jumping, or of slipping; in a word, it may result from any of the 

 causes heretofore considered as instrumental in producing lacerations 

 of muscular, tendinous, or ligamentous structure. 



Symjytoms. — A. hock afi'ected with curb will, at the outset, present a 

 swelling more or less diffuse on its posterior portion, with varying 

 degrees of heat and soreness, and these will be accompanied by lame- 

 ness of a permanent character. At a later period, however, the swell- 

 ing will become better defined, the deformity more characteristic, the 

 prominent curved line readil}'^ detected, and the thickness of the infil- 

 trated tissue easilj^ determined by the fingers. At this time, also, 

 there ma}^ be a condition of lameness, varying in degree, while at 

 others, again, the irregularity of action at the hock will be so slight as 

 to escape detection, the animal betraying no appearance of its existence. 



A curb constitutes, by a strict construction of the term, an "unsound- 

 ness," since the hock thus affected is less able to endure severe labor, 

 and is more liable to give way with the slightest effort. And 3^et the 

 prognosis of a curb can not be considered to be serious, since it gen- 

 erall}" yields to treatment, or at least the lameness it may occasion is 

 generally easily relieved, though the loss of contour caused by the 

 bulging will always constitute a blemish. 



Treatment. — On the first appearance of a curb, when it exhibits 

 the signs of an acute inflammation, the first indication is to subdue this 

 by the use of cold applications as intermittent or constant irrigation 

 or an ice poultice; but when these have exhausted their effect and the 

 swelling has assumed better defined boundaries, and the infiltration of 

 the tendons or of the ligaments is all that remains of a morbid state, 

 then every effort must be directed to the object of effecting its absorption 



