RINGBONE— OSSIFICATION OF CARTILAGES. 301 



th(! 0? suiFraginis, and the latter when the seat is the paifcs around 

 its union with the os pedis or coffin bone. Very often, and espe- 

 cially in heavy cart or dray horses, ringbone and sidebo.ie co- exist 

 in the same leg, where the three bones are completely anchylosed, 

 and in which, during life, the only action was in the fetlock joint. 

 The disease attacks the hind leg as well as the fore ; but it is 

 more common in the latter than in the former. 



The symptoms are a greater or less enlargement of the leg, of a 

 hard and unyielding nature, either immediately above the coronet, 

 as in sidebone, or a little higher, as in ringbone. In the latter 

 case, if thoroughly established, it surrounds the joint, whence the 

 name of ringbone ; but in the early stages it appears at certain 

 points from which it spreads all round. Sidebone is seldom so 

 extensive, and usually attacks the postero-lateral parts of the os 

 coronge, where the swelling is defined, and, except in very hairy- 

 legged or gummy-heeled horses, can easily be felt. In the early 

 stages the action is not impeded, but there is more or less soreness 

 or lameness. After much bone is thrown out, the joints are either 

 completely fixed or their movements are extremely limited. 



The treatment in the early stage is precisely similar to that for 

 splint; but the operation of scarifying the periosteum requires 

 great care and some knowledge of the anatomy of these joints, or 

 the knife will pierce the capsular ligament, and increase the evil 

 it was intended to relieve. A seton without the scarification will 

 often be of service, and for sidebone, firing in the early stage will 

 be serviceable, though it is objectionable on account of the blemish 

 it leaves behind. The biniodide of mercury ointment already 

 described is most useful in slight cases, but in severe ones it will 

 rather tend to aggravate the growth, and when anchylosis has 

 ta*ken place, nothing but time and patience for the subsidence of 

 the inflammation will avail. When this has taken place, and the 

 joint is fixed, a high-heeled shoe will enable the horse to work, 

 with some awkwardness it is true, and the addition of a leather 

 sole, will to some extent take oflF the jar, which occurs in a greatly 

 increased ratio when the elastic action of the pastern joints is 

 destroyed. 



OSSIFICATION OF THE LATERAL CARTILAGES. 

 This is commonly known as ossification of the cartilages, or 

 false ringbone, no other cartilages being subject to ossification, 

 and these being therefore known par excellence as the cartilages. 

 In heavy cart-horses it oflen co-exists with ringbone and sidebone, 

 especially the latter ; but it also attacks well-bred carriage-horses, 

 and high actiuned hacks, which are comparatively free from those 

 diseases. 



The symptoms sr'^. more o^ less enlargement of the back of the 



26 



