38 8PEAINS. 



If we examine the movements of the horse in the gallop or canter, 

 we shall note that after the leading fore has been brought down on 

 the ground (Fig. 10), the fetlock descends (Fig. 11), by reason of the 

 weight of the body being thrown on it, during which time most 

 of the strain falls on the check ligament and suspensory ligament. 

 When the fetlock has reached its utmost limit of descent, the fore- 

 hand is raised by the straightening of the leading fore leg (Figs. 12 

 and 13), which is slightly aided in the canter by the straightening 

 of the non-leading fore leg. It is evident that the straightening of 

 the fetlock joint is accomplished by the muscles of the back tendons, 

 which are consequently liable to sprain at that time, especially if 

 the ground is so '' holding " as to offer resistance to the withdrawal 

 of the foot from the soil. The back tendons of the hind limbs are 

 apt to get sprained when the horse is drawing heavy loads, because 

 propulsion is obtained by straightening of the legs. 



SPRAIN OF THE CHECK LIGAMENT.— This injury is common 

 among cart-horses. It also occurs to saddle-horses, in which case 

 it appears to be invariably the result of a sudden jerk, caused by 

 the animal placing his foot on some inequality of the ground. I 

 have known several instances of it happening to racehorses that 

 were exercised on courses which were cut up by ruts of wheels, etc., 

 crossing them. As I have already pointed out, the check ligament 

 in connection with the portion of the perforans tendon beneath it, 

 serves as an assistant brace to the suspensory ligament, which may 

 become divided, and the fetlock pad may come to the ground, 

 without the check ligament being injured at all. That this sprain 

 must occur during extension (descent) of the fetlock, is evident ; 

 because the moment the foot is flexed, the check ligament is thrown 

 into a state of rest. Again, it rarely happens during the gallop 

 on level ground, at which pace there is extreme extension of the 

 foot at each stride. Hence, it strikes me that the usual manner 

 in which it gets sprained, is by a sudden jerk at a time when tlie 

 upper portion of the perforans tendon is relaxed, so that the whole 

 of the shock has to be borne by this ligament. In the case of a 

 sound cart-horse walking at ease, or going down hill with a hea\^ 

 load behind him, the heel first comes to the ground, then the toe; 

 the heel is now raised, and finally the toe quits the ground. But 

 when he is moving a weight which taxes his strength consider- 

 ably — particularly when drawing it up hill — the toe first meets the 

 ground (Fig. 14), at which moment the flexor muscles are con- 

 tracted, their tendons are in a state of tension, and the check liga- 

 ment is at rest. Then, as the weight is overcome at each stop, the 

 flexor muscles arc suddenly relaxed, and the heel is brought down 

 to the ground with a quick jerk, which is communicated to the 



