The horse, however, which recovers from an attack of laminitis, either in the acute or subacute form, should ever after be shod with leather; and were this admirable practice universal, probably, by deadening concussion, it might altogether eradicate the disease. The expense is the objection to its adoption; but against the cost, the horse proprietor has to ask himself, What are a few shillings extra, at each shoeing, to secure immunity from that horrible disorder to which the servant of his pleasure is exposed?
NAVICULAR DISEASE.
This is the scourge of willing horse-flesh; it is the disease from which favorite steeds mostly suffer; it is not less fatal in its termination than vexatious in its course and painful during its existence.
The malignancy of the disorder is expended upon the substances which in health are without feeling, but which occasion the most acute anguish when affected by disease—namely, bone, tendon, and synovial membrane. Strictly confined to these structures, and frequently limited to a space not half an inch in diameter, the suffering it occasions is such as often provokes the sacrifice of the life, and invariably renders the animal next to useless.
It is confined to the interior of the foot, being, as its name implies, strictly located upon the navicular bone. The navicular bone is a small bone attached to the posterior portion of the os pedis, and resting upon the perforans tendon, which is inserted into the inferior surface of the coffin-bone. A synovial sac is placed between the navicular bone and superior surface of the tendon, on which the ossoeus structure reposes. Synovial sacs are only found in places where motion is great and almost incessant; thus the existence of this formation apprises us that the bone and tendon, in a healthy state, are designed to move freely upon each other. They do this while unaffected by disease; the foot, indeed, cannot be flexed, extended, retracted, or placed upon the ground without this busy little joint being put into motion. It is, perhaps, as essential a part—though of small size—as any of the larger structures which enter into the horse's body.
A DIAGRAM TO EXPLAIN THE SEAT
OF NAVICULAR DISEASE.
a. The perforans tendon running
beneath the bone, and on which
the bone reposes.
b. The comparative size and relative
situation of the navicular bone.
c. The synovial sac which facilitates
the motion of the bone on the tendon;
upon the superior surface of this sac
navicular disease is alone exhibited.