Symptoms.—­Even in its least pronounced form the condition is apparent at a glance, the alteration in the angle formed by the hoof with the ground striking the eye at once, and the heels, as compared with the toe, appearing much too high.  When the condition is slight, the wall of the toe is about twice as high as that of the heels, while in the most marked form the toe and the heels may in height be nearly equal (see Fig. 83).  When congenital, but little interference with the action is noticed.  Such animals, by reason of their ‘stiltiness,’ are unfit for the saddle, but at ordinary work will perform their duties equally well with the animal of normal-shaped feet.  When acquired as the result of overwork, of contracted tendons, or other causes, however, the gait becomes stumbling and uncertain.  The body-weight is transferred from the heels to the anterior parts of the foot, and the shoe shows undue signs of wear at the toe.

Causes.—­Upright hoof is undoubtedly hereditary, and is even seen as a natural conformation in the feet of asses and mules.  When hereditary in the horse, however, it is certainly a defect, and is associated commonly with an upright limb, and a short, upright pastern (see Fig. 83).

Among other causes, we may enumerate sprains or wounds of the flexor tendons, or any disease of the limbs for a long time preventing extension of the fetlock-joint, such as sprains or injuries of the posterior ligaments of the limb, splints or ringbones so placed as to interfere with the movements of the flexor tendons, or, in the hind-limb, spavin, keeping for some months the fetlock in a state of flexion.  In the very young animal the condition may be induced by an improper paring of the foot—­cutting away too much at the toe, and allowing the heels to remain.

Treatment.—­When the condition is congenital, no treatment at all is indicated.  It might, in fact, be said that interference would tend rather to minimize than enhance the animal’s usefulness; for, in this case, the club-shaped feet are in all probability due to faulty conformation above.  In other words, the upright hoof is in this instance but a natural result of the animal’s build, with which useful interference is impossible.

Where the upright hoof is a consequence of excessive paring of the toe, or insufficient removal of the heels, the condition may be remedied by directing attention to those particulars, and preventing their continuance.  At the same time, a greater obliquity of the limb axis may be given by the use of a suitable shoe.  The shoe indicated is a short one, with thin heels and a thick toe.  In some cases the abnormality may be remedied by the use of a tip.  Whatever method is adopted, care must be taken not to attempt too positive a change in the direction of the limb at one operation.  The process must be gradual.

In cases where the abnormality has been brought about by wounds to the flexor tendons, the alteration in the direction of the limb is often so great as to produce ‘knuckling over’ of the fetlock.  This, to a very great extent, may be remedied by the use of a shoe with calkins and an extended toe-piece (see Fig. 84).