FRACTURES OF THE METACARPUS. 825 



Causes. The most frequent causes are kicks, falls, and in small 

 animals, blows with heavy sticks, and injuries from carriages. 

 Sometimes in the horse the large metacarpals of both limbs are 

 suddenly and unaccountably fractured while the horse is cantering 

 at a slow pace on grass. 



Diagnosis is seldom difficult, the abnormal mobility of the parts, 

 the inability to place weight on the leg, and the crepitation pointing 

 clearly to fracture. It becomes, however, more difficult where single 

 bones are involved, but even then careful palpation is generally 

 sufficient, and crepitation can almost always be detected. Fissuring 

 of the cannon bone can seldom be more than guessed at. Such 

 cases have, however, been reported. Like similar accidents in con- 

 nection with the pastern and tibia, fissuring of the cannon bone is 

 apt to culminate, a few days later, in complete fracture. 



Course. In most metacarpal fractures recovery is possible, and 

 in small animals is fairly rapid. Compound fracture of the cannon 

 bone, is, however, seldom hopeful, and in the large domestic animals 

 even subcutaneous fracture must be viewed as relatively incurable. 

 Only in colts or valuable and quiet horses is treatment worth 

 attempting, but that complete usefulness may be regained is shown 

 by many reported cases. The course of fracture of the metacarpus 

 chiefly depends on whether the animal can bear its whole weight 

 sufficiently long on the other foot without producing laminitis and 

 descent of the fetlock or os pedis. Union is readier in cattle than 

 in horses, and in them the lameness occasionally left causes no incon- 

 venience. In the small ruminants and in carnivora subcutaneous 

 fractures unite in three to six weeks. Fractures of the diaphyses 

 of the metacarpal bones- unite more easily than those in the 

 neighbourhood of joints. 



Treatment. Reduction is seldom difficult. Before applying a 

 dressing care must be taken to bring the limb into a proper position, 

 and especial attention should be given to the position of the hoof 

 or claws. In the horse the toe of the hoof, in the ox the interdigital 

 space, is the best guide. A plaster bandage is very useful, especially 

 in small animals. 



Stolz employed an ointment, now named after him, composed 

 of two parts of resin and one of wax, which is smeared on linen, and 

 used as a first dressing, over which a splint is applied. Horses must 

 generally be slung. Pujos saw transverse fracture of the cannon 

 bone, just above the fetlock, in the horse, which united after applying 

 a plaster bandage. Eight days (?) after the accident the animal 

 began to place weight on the limb. Forty-five days later, when the 



