DISEASES OF CATTLE 443 



five stages. In the first stage, including the first eight days, the de- 

 tached portions of the bone and the sharp projections that are not 

 sufficiently nourished are absorbed ; the blood which escaped into the 

 surrounding tissues, the result of the injury, is gradually absorbed, 

 and the effused lymph, which is ultimately to constitute the tempo- 

 rary cartilage, takes its place. In the second stage, from the tenth to 

 the twentieth day, the tumor or callus is formed and fibrocartilage is 

 developed inside and around the exposed end of the bone. In the 

 third stage, extending from the twentieth to the fortieth or fiftieth 

 day, according to the age and strength of the animal, the fibrocar- 

 tilaginous structure undergoes a change and is gradually converted 

 into bone, forming a ferrule on the outside and a plug on the inside, 

 which serve to hold the part in position. In the fourth stage, ex- 

 tending to about the sixth month, the whole of the new structure is 

 converted into bone. The fifth stage, extending up to the end of the 

 first year, the callus is absorbed, being no longer necessary, and the 

 connection between the cavities of the two bones is again established. 

 Common Complications. The process of union just described is 

 healthy and normal. Diseased conditions may at any time super- 

 vene 'during the treatment and render the operation unsuccessful. 

 In the case of compound fracture, the open wound communicating 

 with the ends of the bones, a septic condition is apt to arise which 

 may become so serious as to endanger the animal's life and bring 

 about conditions which in human surgery would indicate amputa- 

 tion. Although that operation is not a general one in veterinary 

 practice, there is no reason why it should not be attempted as a last 

 resort, particularly if the animal be valuable or one whose existence 

 is necessary in order to perpetuate some valuable strain. Even in 

 the simplest form of fracture, if the splints or bandages are improp- 

 erly applied and the fractured bone left so loosely guarded that the 

 broken ends move one upon another, the formation of the calluses 

 previously described is likely to be interfered with, and in place of a 

 strong, rigid, and healthy union a formation of elastic cartilage is 

 the result. This false structure unites the broken ends of the bones 

 in such a way that they move one upon another, depriving the bone 

 of its stability and .usefulness. When once the healthy process of 

 union is interrupted in the manner just described, it is with great 

 difficulty that it can be again established. It no longer does any 

 good to continue the restraining power; in fact, the change of the 

 temporary cartilage into bone is more likely to be re-established if 

 the parts move violently upon one another for a short time so as to 

 set up and renew the process of inflammation. Then if the restraint 

 be again applied there is some chance of union. In order so far as 

 possible to avoid this danger, care should be exercised that the ban- 

 dage fits closely and that it is kept on till there is no longer any dan- 

 ger but that a perfect union has taken place. It is impossible to say 

 at just what time the splints or bandages can safely be removed. In 

 a young and healthy animal of quiet temperament, where the parts 

 have been firmly held in position throughout the whole time, from 

 thirty to forty days may be regarded as reasonably safe. Under more 



