790 FRACTURE OF THE RADIUS. 



killed. Giinther says foals recover. In man, transverse fractures 

 of the olecranon only reunite by fibrous callus, because, it is said, 

 of the displacement of broken fragments by the pull of the muscles, 

 and of the failure to form bony callus on account of the absence 

 of periosteum. On the other hand, A. Cooper has shown by ex- 

 periments on dogs that in longitudinal fracture of the olecranon 

 a bony callus always forms. The unfavourable course which trans- 

 verse fracture of the ulna takes in the horse must be referred to 

 the great dislocation produced by the pull of the triceps muscle, 

 and to the fact that the fracture almost always extends to the 

 articular surface. Fig. 463, drawn from nature, shows a typical 

 fracture, such as is usually seen in horses. Moller never had a 

 recovery. Under exceptionally favourable circumstances, fracture 

 of the ulna may reunite. In pigs, dogs, and cats, in which the 

 ulna forms a bone distinct from the radius, recovery is much 

 commoner, the radius acting to some extent as a splint for the 

 broken ulna. 



Treatment. As in horses and ruminants no effective bandage 

 can be applied at this point, treatment is confined to keeping the 

 animal quiet, or possibly to placing it in slings. The action of the 

 triceps muscle interferes with healing, and therefore it is best to 

 prevent animals lying down, and in horses this is easily effected 

 by slinging or by fastening them up short. In carnivora a plaster 

 bandage assists recovery, but is somewhat difficult to apply. To 

 ensure its remaining in place the bandage should be passed over 

 the back and between the fore-legs, reversing the direction alternately. 



II.— FRACTURE OF THE RADIUS. 



In the horse, fracture of the radius is not usually accompanied 

 by fracture of the ulna. In other animals it is sometimes seen with, 

 sometimes without, fracture of the ulna. In dogs the fore-arm is 

 most frequently fractured by the animals being run over, or being 

 squeezed or kicked ; in larger animals it results from kicks, falls, 

 and slipping whilst getting up, &c. Freer, in a horse, saw fissuring 

 of the radius which, a fortnight later, was fractured. 



In ruminants and carnivora, diagnosis is only difficult when the 

 ulna remains intact, and crepitation is absent. Careful examination, 

 however, shows abnormal mobility, crepitation, swelling, and pain. 

 Not infrequently the broken ends perforate the soft tissues and 

 produce a compound fracture. 



Prognosis and course. Subcutaneous fractures of the radius 



