356 HEALTH AND DISEASE 



joint is a separate and distinct sac. This, however, is not necessarily 

 the case. For the most part they result from a distended state of 

 the synovial sheath that invests the flexor tendons from a point just 

 above the fetlock to the foot. That the swelling is not observed along 

 the entire length of the sheath results from the fact that at certain points 

 it is tightly bound down by strong ligaments, while the intervening spaces 

 where the bulging takes place off'er only slight resistance to its outward 

 pressure; all the same, there is a general over-fulness of the sheath from 

 one end to the other. 



Causes. — Wind-galls, like the kindred ailment thoroughpin, are un- 

 questionably hereditary. Besides this predisposing influence, it is also 

 observed that horses of lymphatic temperament, i.e. such as have a thick 

 skin, coarse hair, fleshy legs, exhibit a special liability to the disease, as do 

 also animals with heavy fleshy bodies and small limbs. 



The exciting causes are long-continued severe work, which is especially 

 operative in the case of young immature animals and such as are in- 

 diff"erently nourished. Repeated sprain to the tendinous sheath from heavy 

 draught, slipping, and other forms of violent exertion very largely conduce 

 to bring about the disease. 



They are also a result of long standing in a confined space in the course of 

 protracted illness, such as influenza, pneumonia, pleurisy, and rheumatism. 



Symptoms. — Wind-galls are readily identified as small boggy swell- 

 ings in the vicinity of joints, varying in size from a hazel-nut to a small 

 hen's egg. In the fetlock -joints they occur on the inner and outer side at 

 the same time. The more material enlargements appear behind and above 

 the fetlock-joint between the suspensory ligaments and the flexor tendons. 

 They usually come by slow growth, and are at first soft and yielding, but 

 as they increase in size they get hard and tense, especially when the foot is 

 on the ground. Excepting when associated with rheumatism or sudden 

 sprain they seldom give rise to acute lameness, and it is only when of 

 considerable size, and the mechanical play of the tendons and joint are 

 interfered with, that the action becomes materially disturbed. At this time 

 there is more or less heat in the part, and digital pressure occa.sions 

 marked pain. 



Treatment. — In this connection it may be said that the best and most 

 lasting results are obtained when treatment is resorted to in the early 

 stages of the disorder, while the walls of the joint capsule or tendon -sheath 

 are still free from serious structural change. When by protracted irritation 

 and neglect they have become thickened and callous it is hopeless to think 

 of bringing the membrane back to a normal state, although further advance 

 of the disorder may in some measure be kept in check. 



