324 Surgical Diseases and Surgery of the Dog 



forations, or depressions, usually in flat bones, such as those of the 

 skull. To these must be added subperiosteal or the so-called green- 

 stick fractures in which the periosteum remains intact. 



Complete fractures are observed in long bones and form the 

 majority of all fractures. 



A fracture is said to be compound when a wound exposes it 

 to the atmosphere. 



A fracture is said to be comminuted when it is shattered into 

 a number of fragments. 



The immediate result of a fracture is hemorrhage from the 

 local vessels or those of adjacent parts which may be involved 

 in the injury. Inflammation is precipitated, giving rise to hypere- 

 mia and swelling of the contiguous tissue. In a few days these 

 subside, and finally there arise reparative processes associated with 

 callous formation. The process of solidification of the callus is 

 complete within fifteen to thirty days. Stockfleth observed com- 

 mencing ossification of the callus in a fracture of one of the lower 

 extremities, twelve days after receipt of the injury. It is more 

 rapid in the young and slower in the old. The ensheathing portion, 

 becomes absorbed within thirty to sixtji days, while the central 

 callus remains for a while, completely occluding the medullary canal, 

 but it also undergoes absorption at a later period. 



Muscular action; particularly in cases of oblique fracture, may 

 cause considerable overriding of the broken extremities, the latter - 

 being sometimes separated from one another such distance as to 

 make it no easy matter to replace them in correct apposition. 



Separation of the epiphyses frequently occurs in very young 

 animals through slight traumatic influences or excessive motion. 



Symptoms and Diagnosis. The chief symptoms are: Local 

 pain and swelling, more or less distortion of natural outlines, loss 

 of function, preternatural mobility in all directions, and crepitus. 

 Crepitus, however, is not invariably present, as when muscular fibers 

 or tendons become interposed between the fractured extremities or 

 when the hemorrhage is considerable. 



Separated epiphyses are distinguished from luxations with diffi- 

 culty. Crepitus is less noticeable than in true fracture, being 

 "softer," and it may be entirely absent. 



Treatment. The object to be attained in treating a fracture 

 is reduction of any existing displacement of the broken ends and 



