DISEASES OF THE TENDON AND TENDON SHEATH. 1035 



coloured fluid. The thickened synovial membrane was covered with 

 granulations, the cartilage of the fetlock-joint showed local ulceration, 

 and the portions of bone thus exposed were granulating. Microscopical 

 examination of the discharges and granulations revealed the presence of 

 tubercle bacilli. 



(e) Distension of the sesamoid sheath at the fetlock (tendinous 

 windgall) is commoner in the hind than in the fore limb. As a rule, 

 it is caused by irritation, and forms slowly. Lameness, is seldom 

 troublesome until the flexor tendons are affected ; but the swelling 

 forms a blemish difficult to remove. Provided the swelling has not 

 long been in existence, the parts should be tightly bandaged after 

 work ; massage often removes the distension in young horses, but 

 firing is more effective. The swelling should never be incised, for 

 the result is often fatal. Removal of contents by a Pravaz syringe, 

 or by trocar, is only of temporary benefit ; nor does injection of 

 iodine prevent refilling, which may occur in a few minutes. The 

 precautions to be observed in opening these swellings with the actual 

 cautery are mentioned under " Treatment of Enlarged Synovial 

 Cavities in the Fore Limb." 



In the hind limbs such enlargements often become indurated, i.e., 

 the tendon sheath is thickened, sometimes to the extent of | or 

 | of an inch. As a rule, the flexor tendons are involved, and there 

 is chronic lameness, the horse going on the toe with the heel more 

 or less raised. The swellings are hard and immovable, the flexor 

 tendons can scarcely be felt through them, and when the parts are 

 firmly pressed the animal shows pain. 



Such enlargements are most troublesome in riding and draught 

 horses, though, in other animals, they interfere with usefulness and 

 sometimes render the horse unworkable ; they are little amenable to 

 treatment. When recent, i.e., not more than a few weeks old, they 

 may be diminished by the use of bandages, blisters, or firing, but 

 later the sole means of removing the lameness is neurectomy of the 

 posterior tibial nerve. Good results often follow this operation, but 

 occasionally the flexor tendons become elongated, producing flexion 

 of the hock and sinking of the fetlock ; in a case of Moller's this was 

 so marked as to prevent the animal being used. Hendrickx has 

 had similar results. 



As in the fore extremity, dilatations of the synovial membrane 

 of the fetlock joint also occur in the hind-limb, forming swellings 

 (articular windgalls) in front of the suspensory ligament and on the 

 lateral surfaces of the fetlock. At first they are compressible, 

 diminishing at exercise and readily disappearing under bandaging ; 

 later, owing to thickening of their walls, they are more resistant, 



