272 DISEASES ; OF BONE. 



differed from that of tke hook, except that it ran a more acute 

 com-se. I would therefore be inclined to class them both under 

 the one heading of rheumatoid arthritis. 



(3.) An inflammation of the joints of the limbs of foals, without 

 formation of pus, and probably connected with navel-ill (p. 532). 

 In the two or three cases I have seen, the animals were from three 

 to five months old. The first symptom noticed was decrease in 

 power of movement from one place to another, and fatigue from 

 comparatively slight exertion. There was gradual swelling of the 

 joints, chiefly of the hock, stifle, knee and fetlock, and also swell- 

 ing of the front of the cannon bones. The animals knuckled over 

 more and more on all four legs until they were unable to walk, 

 and could stand only with difficulty, so that they had to be 

 destroyed. During the course of the disease, which lasted for 

 about two months, they remained in good condition, their general 

 health was apparently unimpaired, and the inflamed joints were 

 not painful to the touch. Tke affected joints, by post-mortem 

 examination, showed all the signs of rheumatoid arthritis, in- 

 cluding the ivory-like deposit on the denuded ends of the bones. 

 The age of the sufferers, the rapid progress of the disease, and its 

 general attack on the joints of all four limbs, point, I venture to 

 think, to infection as the cause, and justify the separation of this 

 disease from the rheumatoid arthritis of adult and old horses, 

 which form of inflammation has a close connection with injury 

 or at least hard work. In these foal cases, the inflammation was 

 persistent, and did not show any tendency to shift from one joint 

 to another, which is a peculiarity of the inflammation of true 

 rheumatism. 



TREATMENT appears to be of no avail. A horse slightly 

 affected should be put only to light labour. In the stable, he 

 should be induced to lie down as much as possible. 



Stiff Joints and Knuckling Over. 



GENERAL REMARKS. — I shall confine my attention, under this 

 heading, to the joints of the fetlock and knee. 



We are all aware of the tendency which the pastern, especially 

 of horses used at fast paces, has to become unduly upright from 

 the effects of work. If we examine the joint, we shall find that 

 this upright condition of the pastern is owing to inability to 

 extend the joint to a normal extent; in other words, to bring 

 the fetlock pad sufficiently near the ground. As the action of 

 a limb in producing locomotion is due to the difference between 

 its length when its joints are bent and its length when they 



