KNUCKLING OF FETLOCK. 347 



The action of blisters in these cases depends chiefly upon the massage 

 used in applying them and upon the continuous pressure of the swol- 

 len skin on the inflamed tendons. In old cases more beneficial results 

 will follow line firing. In these cases shoeing is very important. 

 Leave the quarters long, shorten the toe, give the shoe rolling motion, 

 and either put short heel calks on the branches or thicken the 

 branches. Although this line of treatment is efficacious in many cases, 

 there are others in which the thickening of the tendons refuses to 

 yield and the changed tissues remain firmly organized, leaving them 

 in the form of a thick mass resting upon the back part of the cannon 

 bone. 



KNUCKLING OF FETLOCK. 



As a consequence of the last-mentioned lesion of the tendons, a new 

 condition presents itself in the articular disposition, constituting the 

 deformity known as the knuckling fetlock. (See also page 374.) 



By this is meant a deformity of the fetlock joint by which the nat- 

 ural angle is changed from that which pertains to the healthy articu- 

 lation. The first pastern, or suffraginis, loses its oblique direction and 

 assumes another, which varies from the upright to the oblique, from 

 before backward, and from above downward; in other w^ords, form- 

 ing an angle with its apex in front. 



Causes. — This condition, as we have seen, may be the result of 

 chronic disease producing structural changes in the tendons, and it 

 may also occur as the result of other affections or some peculiarity 

 independent of this and situated below the fetlock, such as ringbones, 

 sidebones, or traumatic disease of the foot proper. Animals are 

 sometimes predisposed to knuckling, such, for example, as are natur- 

 ally straight in their pasterns, or animals which are compelled to 

 labor when too young. The hind legs are more predisposed than the 

 fore to this deformity, in consequence of the greater amount of labor 

 they are required to perform as the propelling levers of the body. 



Symptoms. — The symptoms of knuckling are easily recognized. 

 The changes in the direction of the bones vary more or less with the 

 degree of the lesion, sometimes assuming such a direction that it 

 almost becomes a true dislocation of the pastern. 



The effect of knuckling upon the gait also varies according to the 

 degree of the deformity. As the different degrees of the shortening 

 of the leg affect the motion of the fetlock, the lameness may be very 

 slight or quite extreme. Another consequence of this shortening is 

 such a change in the position of the foot that the heels cease to come, 

 in contact with the ground and assume a greater elevation, and the 

 final result of this is soon witnessed in the development of a clubfoot. 



Treatment. — To whatever cause the knuckling may be ascribed, it is 

 always a severe infirmity, and there is but little room for hoping to 

 overcome it unless it be during the very first stages of the trouble, 



