252 HEALTH AND DISEASE 



completely across the bone, the broken fragments are forced asunder by 

 the weight imj^osed upon them, and the fetlock joint, having lost the 

 support of the suspensory ligament, sinks towards the ground. The 

 weight, now falling more directly upon the heel, gives the toe an inclina- 

 tion upwards. This deformity may not occur immediately, and sometimes 

 only a^jpears two or three days after the accident, at which time there 

 is much swelling, heat, and pain in the part. It may be that only one 

 sesamoid bone may be fractured, in which case the fetlock joint inclines 

 inward or outward, according as the one side or the other is affected. 

 Although the broken pieces may be much disi^laced, crepitus may some- 

 times be induced by fixing the suspensory ligament above and forcibly 

 flexing the fetlock joint. 



Treatment. — Very little can lie done in these cases to fit the horse 

 for remunerative work, but when it is required to jjut it to the stud, 

 in some cases it may be made serviceable for the purjDose. 



The strain should be taken off the suspensory ligament by the appli- 

 cation of a high-heeled shoe. The joint should then be supported by a 

 starch bandage, carried from the coronet upwards to the middle of the 

 canon. This having been done, the animal should be placed in slings and 

 kept there eight or ten weeks, or longer if necessary, as quiet as possible. 



In complete fracture, the fetlock joint is sure to remain deformed and 

 enlarged to a greater or less extent. A repetition of blisters after the 

 patient has been taken out of the slings will help to reduce the enlarge- 

 ment, and give further tone to the injured parts. 



FRACTURE OF THE NAVICULAR BONE 



Tlie frequent occurrence of navicular disease, as a result of which the 

 bone becomes weakened by ulceration and rarefaction of its tissue, renders- 

 the bone in question peculiarly liable to fracture, and this predisposition 

 is still further increased by the position which it occupies, and the weight 

 and concussive force to which it is exposed during locomotion. 



It is, however, more particularly in horses the nerves of whose feet 

 have been divided that the accident occurs. While the nerves are intact, 

 and sensation exists in the feet, the animal relieves himself from pain by 

 throwing the weight of the body on the front of the foot, but when 

 sensation has been removed by division of the nerves, pain disappears. 

 The heels are then brought to the ground, and the navicular bone, 

 weakened by disease, is made to bear the full weight and impact of the 

 body. 



At this time the perforans tendon has undergone more or less 



