234 DISEASES OF BONE. 



CAUSES. — In young and healthy horses, each of the splint 

 bones is attached to the cannon bone by a strong interosseous 

 ligament, which, with advancing years, tends to become converted 

 into bone. In the large majority of cases, bony deposits (with the 

 exception of " sore shins ") on the leg between the knee and the 

 fetlock, appear somewhere at the junction of a splint bone and the 

 cannon bone, and usually occur during youth, before bony union 

 has taken pleice between the cannon bone and the splint bones. It 

 may fairiy be surmised that they are brought on in the majority of 

 cases, by inflammation having been set up in the part by sprain 

 of the interosseous ligament. This view is further-strengthened 

 by the fact, which I shall presently attempt to explain, of splints 

 occurring more frequently on the inside than on the outside of the 

 leg. This sprain of the interosseous ligament gives rise to inflam- 

 mation of the periosteum (the covering membrane of bone) with 

 consequent deposition of bony material. When the bony en- 

 largement is confined to the cannon bone, it may be taken for 

 granted that it has been caused by a blow. Violent shock trans- 

 mitted longitudinally through the column of bones between the 

 knee and fetlock is, naturally, the great cause of splints, which 

 consequently often result from fast movement, especially on hard 

 ground. He nce this disease is chiefly caused by trotting on hard 

 mads. Ids evident that the higher the action and the heavier 

 the body of the horse, the more liable will he be to get splints.^ 

 Jumping is also a cause of splint. The more unused a horse is 

 to jumping, the more liable is it to cause a splint ; because 

 practice teaches the animal to regulate his movements so as to 

 more or less diminish the disagreeable, if not actually painful, 

 effects of concussion. 



Splints are to be found on the hind legs as well as on the fore 

 legs ; but as the former are much less exposed to the efiects of 

 concussion than the latter, splints on them are rarely of serious 

 detriment to the animal. This fact, and the less degree of atten- 

 tion usually given to the hind limbs than to the fore, are no 

 doubt the chief reasons why ignorant stablemen frequently 

 neglect to notice the existence of splints on the hind extremities. 

 Fig. 96 shows a splint on the inside of the near hind, and close 

 to the hock ; and Fig. 78, one on the outside of the off hind, arid 

 also close to the joint. 



The absence, as a great rule, of marks of wounds of the skin 

 immediately over a splint on the inside of the leg, leads me to think 

 •that a splint (using the term in its ordinary meaning) seldom 

 occurs from a blow with the other fore leg or with a hind leg as 

 the case may be. Of course, a bony deposit is often the result of 

 "speedy cutting;" but English veterinary surgeons do not apply 



