224: OPERATIONS ON BONES. 



horse, after running away in a fright caused by the whistle of a 

 locomotive, was found on the road limping with excessive lame- 

 ness in the off fore leg, and walked with comparative ease some 

 two miles to a stable before being seen by a surgeon. His imme- 

 diate removal in an ambulance was advised, but before that vehi- 

 cle could be procured the horse laid down, and upon being made 

 to get upon his feet was found with a well-marked comminuted 

 fracture of the os suffraginis, with considerable displacement. 

 The patient, however, after long treatment, made a comparatively 

 good recovery, and though with a large bony dej^osit, a ringbone, 

 was able to trot among the forties. 



The two obvious indications in cases of fracture are reduction, 

 or replacement and retention. 



In an incomplete fracture, where there is no displacement, the 

 necessity of reduction does not exist. With the bone kept in 

 place by an intact periosteum, and the fragments secured by the 

 uninjured fibrous and ligamentous structure which surrounds 

 them, there is no dislocation to correct. It is also at times ren- 

 dered imjDOSsible by the seat of the fracture itself, by its dimensions 

 alone, or by the resistance arising from the muscular contraction 

 excited by the surgical manipulation. This is illustrated even in 

 small animals, as in dogs, by the exceeding difficulty encountered 

 in bringing the ends of a broken femur or humerus together, the 

 muscular contraction being even in these animals sufficiently for- 

 cible to renew the disi^lacement. 



It is generally, therefore, only fractures of the long bones, and 

 then at 2:)oints not in close proximity to the trunk, that may be con- 

 sidered to be amenable to reduction. It is true that some of the 

 more superficial bones, as those of the head, of the pelvis, and of 

 the thoracic walls may in some cases require special manipulations 

 and appliances for their retention in their normal positions, but 

 the treatment of these and of a fractured leg cannot be the same. 



The methods of accomplishing reduction vary with the features 

 of each case, the manij^ulations being necessarily modified to meet 

 changing circumstances. If the dis^Dlacement is in the thickness 

 of the bone, as in transverse fracture, the manipulation of reduc- 

 tion consists in applpng a steady pressm-e vij)on one of the frag- 

 ments, while the other is kept steady in its place, the object of the 

 l^ressure being the re-establishment of the exact coincidence of the 

 two bony surfaces. If the displacement has taken place at an 



