322 DISEASES OF THE HORSE. 



FRACTURES. 



In technical language a fracture is a " solution of continuity in the 

 structure or substance of a bone." It ranks among the most serious 

 of the lesions to which the horse — or any animal — can be subject. 

 It is a subject of special interest to veterinarians and horse owners 

 in view of the fact that it occurs in such a variety of forms and 

 subjects the patient to much loss of time, resulting in the suspension 

 of his earning capacity. Though of less serious consequence in the 

 horse than in man, it is always a matter of grave import. It is 

 always slow and tedious in healing and is frequently of doubtful 

 and unsatisfactory result. 



This solution of continuity may take place in two principal ways. 

 In the most numerous instances it includes the total thickness of the 

 bone and is a complete fracture. In other cases it involves only a 

 portion of the thickness of the bone, and for that reason is described 

 as incomplete. If the bone is divided into two separate portions 

 and the soft parts have received no injury, the fracture is a simple 

 one, or it becomes compound if the soft parts have suffered lacera- 

 tion, and comminuted if the bones have been crushed or ground into 

 fragments, many or few. The direction of the break also determines 

 its further classification. Broken at a right angle, it is transverse; 

 at a different angle it becomes oblique, and it may be longitudinal 

 or lengthwise. In a complete fracture, especially of the oblique 

 kind, there is a . condition of great importance in respect to its effect 

 upon the ultimate result of the treatment in the fact that from vari- 

 ous causes, such as muscular contractions or excessive motion, the 

 bony fragments do not maintain their mutual coaptation, but be- 

 come separated at the ends, which makes it necessary to add another 

 descriptive term — with displacement. These words again suggest 

 the negative and introduce the term without displacement, when 

 the facts justify that description. Furthermore, a fracture may be 

 intra- articular or extra-articular, as it extends into a joint or other- 

 wise, and, once more, intra-periosteal when the periosteum remains 

 intact. Finally, there is no absolute limit to the use of descriptive 

 terminology in the case. 



The condition of displacement is largely influential in determining 

 the question of treatment and as affecting the final result of a case of 

 fracture. This, however, is dependent upon its location or whether 

 its seat is in one or more of the axes of the bone, in its length, its 

 breadth, its thickness, or its circumference. An incomplete fracture 

 may also be either simple or comminuted. In the latter case the frag- 

 ments are held together by the periosteum when it is intact ; in that 

 case the fracture belongs to the intraperiosteal class. At times, also, 

 there is only a simple fissure or split in the bone, making a condition 

 of much difficulty of diagnosis. 



