In adult and aged horses the metacarpal bones are generally united together by ossific union, and it results from this, when fracture occurs, that all the bones are involved in it. In colts, where they are united by ligaments only, each one of them may be broken independently of the others, but such an occurrence is very occasional.

Fracture of these bones (fig. 326, p. 222) is mostly brought about by kicks, jumping into deep hard roads, blows against fences and walls, and slips, etc.

The absence of muscles in this region, and the opportunity thus afforded of a clear view and thorough manipulation of the part, renders diagnosis an easy matter when displacement has occurred. The bone will be seen to bend at the seat of fracture when any attempt is made to put weight upon it. In progression, that part of the limb below the breach has ceased to be under control. and swings about as the body moves forward. Crepitus can be readily produced, and the existence of a fracture becomes at once apparent.

Treatment

Although these cases are both difficult and uncertain, now and again treatment has its reward in restoration to a state of usefulness, but it is seldom possible to avoid depreciation in the value of the animal. To what extent this factor will assert itself will depend very much upon the degree of displacement and the damage inflicted upon surrounding tissues by the unrestrained movement of the broken fragments after the accident.

Fractures without displacement, when they are diagnosed and promptly treated by slinging and suitable splints, offer the best prospects of success.

Fig. 338. - Splint for Fracture of the Metacarpal Bones.

Where displacement occurs, the bone must be set, and in carrying out this part of the work every care will require to be taken that the fragments are brought into their proper position. Before splints and bandages (fig. 338) are applied, the knee and the toe must be brought into line, and the leg as a whole rendered straight. Placed in slings, the patient must be disturbed as little as possible, and careful watch kept over the limb, so that prompt relief may be given by relaxing the bandages where undue pressure provokes swelling.

Should this precaution fail to be observed, the case will become complicated by dangerous sloughing, and the reunion of the bone retarded or altogether prevented.