FETLOCK JOINT. 



43 



confined to the synovial bursa which lies between the suspensory 

 ligament and tlie cannon bone. This niay be felt in tlie form of a 

 pufl'y swelling- on each side of the fetlock by the forefinger and 

 thumb when the hand is placed on the joint, as in Fig. 19, By 

 alternating the pressure with finger and thumb, the fluid will be 

 felt to pass through from one side to the other. In health, no 

 distension of this bursa will be present. As an inflammatory 

 swelling is liable to invade neiglibouring parts, tlie difficulty of 

 finding out the exact seat of the injury will be increased after a 

 short time. 



In the more serious case of sprain, the vacant spiace between the 



Fig. 19. — Site of windgall caused by sprain of letlock. 



back tendons and suspensory ligament, just above the joint, may 

 also become filled with synovial fluid ; in other words, a windgall 

 n.ay be formed. Possibly in these ca.ses there is more often sprain 

 of one or both of the lateral ligaments of the joint (the outer one 

 more frequently than the inner one) than of tlie suspensory liga- 

 ment. It appears to be caused by a twist being given to the leg. 

 usually when the horse is making a sharp turn at a fast pace. If 

 the bursa, which is Vjetween the sesamoid bones and the perforans 

 tendon, is distended, so as to take the form of a hard swelling at 

 the back of the fetlock, the case may be regarded as very grave. 

 This symptom often denotes an injury but little amenable to 

 treatment, which is known as sesamoiditis. If pressure be put on 

 one side of this swollen bursa, it will bulge out on the other side. 



