CHAPTER IX.

SHOEING BAD FEET.

Any average farrier can shoe without immediate harm a good well-formed foot that has a thick covering of horn, but when the horn is deficient in quantity or quality injury soon takes place if a badly fitted shoe be applied. There are feet which from disease or accident or bad shoeing have become, more or less, permanently damaged. Some are seriously altered in shape. Some are protected only by an unhealthy horn, and some show definite changes which cause weakness at a special part. These are the feet which really test the art of the farrier, for he must know just what to do and what not to do, and must possess the skill to practice what he knows.

=Flat Feet.= Some horses are born with flat feet, others acquire them as the result of disease. Too often the flat sole has another defect accompanying it--low weak heels. Such feet are best shod with a seated shoe so as to avoid any uneven pressure on the sole, and the shoes should always be fitted a little longer than the bearing-surface of the foot, so as to avoid any risk of producing a bruise at the heel--in other words, of causing a corn. The seated shoe is not advisable on a hunter. The concave shoe used for hunters has many distinct advantages and only one disadvantage for a flat foot, viz, that it has a wide flat foot-surface. It may cause an uneven pressure at the toe on a flat sole, but this is easily avoided by not making it too wide; perhaps the very worst thing to do with a flat foot is to try and make it look less flat by paring it down. The thinner the horn the greater the chance of injury to the sensitive parts under it, and every injury tends to make the sole weaker. Leaving the sole strong and thick, whilst fitting the shoe to avoid uneven pressure, is the principle of shoeing to be adopted with flat feet.

=Convex Soles.= The sole of the foot should be concave, but as the result of disease many feet become convex. This bulging or "dropping" of the sole varies in degree from a little more than flat to an inch or so below the level of the wall. When the under-surface of a horse's foot resembles in form the outside of a saucer, fitting a shoe becomes a work of art. Very often the wall is brittle and broken away and it is most difficult to find sufficient bearing-surface on the foot for a shoe. Many of these feet may be safely shod with a narrow shoe that rests only on the wall and the intermediate horn between the wall and sole. Such a shoe may, according to the size of the foot, be five-eighths or even three-quarters of an inch wide. Its thickness is to be such as will prevent the sole taking any direct bearing on the ground, and sometimes a shoe of this form is much thicker than it is wide. The advantage of this shoe is that it is so narrow that any bearing on the sole is avoided. The disadvantage is that on rough roads the sole may be bruised by the flint or granite stones. When the horn of a "dropped" sole is very thin, or when the horse has to work on roads covered with sharp loose stones, some cover for the sole is necessary and the narrow shoe is not practicable. To provide cover for the sole, the web of the shoe has to be wide, and, therefore, the foot-surface of the shoe must be seated out so as to avoid contact with the sole. Too often the seating is continued from the inner to the outer border of a shoe, so that no level bearing-surface is provided for the wall to rest on. This kind of shoe is like the hollow of a saucer, and when applied to a foot is certain to cause lameness soon or later. Each time the horse rests his weight on it the hoof is compressed by the inclined surface of the shoe, which instead of providing a firm bearing-surface affords only an ingenious instrument of torture.

In even the worst of these deformed feet some good sound horn is to be found at the heels, where an inch or sometimes two can be utilised for level bearing. No matter how much seating is required at the toe and quarters, the heel of the shoe may always be made level.

It cannot be too strongly urged that in the preparation of feet with bulging soles no horn is to be removed from the sole. The toe is to be shortened, the heels lowered proportionately, and the bearing-surface of the wall made level with a rasp. At no place must the shoe rest on the sole. In nearly every case the toe is left too long and the bearing taken upon it by the shoe only increases the deformity. In many feet a large slice might be sawn off the toe with advantage, as the sensitive foot is separated from the wall by a mass of diseased horn which presses the wall at the toe forward. (Fig. 81).

=Sandcracks.= This is the name given to cracks in the wall which commence at the coronet and extend downwards. From their position at the toe, or at the side of the hoof, they are sometimes called respectively "toe-cracks" and "quarter-cracks." The crack may be very slight and may exist without causing lameness. It may appear suddenly, accompanied by great lameness and by the issue of blood from between the edges of the divided wall. These are grave cases which require surgical attendance. Sandcracks are most commonly seen in dry brittle feet, and the horses most subject to them are those employed in heavy draught work. Railway shunt-horses and omnibus horses are very liable to be troubled with sandcracks in the toe of the hind feet.

In shoeing for this defect there are two things to avoid, (_a_) not to place any direct pressure on the part; (_b_) not to fit a shoe which will tend to force the crack open. Following these lines it is well not to put a clip exactly over a crack. If at the toe place a clip each side of the crack, and never use calkins or high heels which throw the weight forward. If at the quarter avoid a spring-heeled shoe which permits the downward movement of the foot behind the crack and so forces it open. In all cases, after fitting the shoe level to the foot, remove a little more horn just below the crack so as to relieve the direct bearing on the part. (Fig. 82).

In the case of crack extending the whole space of the wall some provision should always be made to keep it from opening, because every step of the horse, especially when drawing a load, causes an outward pressure at the coronet. This pressure forces the hoof apart and the injury caused does not cease with the pain and lameness which follow, and which may be temporary. Doubtless the original cause of a sandcrack is some morbid condition of the coronary band--the band from which the wall grows. The sensitive laminæ are at first not affected further than by the inflammation consequent upon the direct tearing which occurs when the crack takes place. The continued irritation, kept up by a persistent fissure in the horn covering the laminæ, soon causes other serious changes which tend to make the sandcrack a permanent disease. Thus even the smallest crack should be attended to and measures adopted to prevent its enlargement or, when extensive, to limit all opening and shutting movement of the hoof.

This is sometimes attempted by a simple leather strap tightly applied, or by binding the foot with string or tape. Tape is less liable to slip than string. When the hoof is sufficiently thick two nails may be driven in opposite directions transversely through the crack and clinched; or French sandcrack-clips (Fig. 83) may be used which are easily applied. The instruments necessary are shown below (Fig. 84). The iron (_b_) is made red-hot and pressed on the hoof over the crack so as to burn a groove each side of it. Into these grooves the clip (_a_) is put and the pincers (_c_) are then used to compress the clip firmly into its place. There is a strain upon the clips, and sometimes one breaks. It is therefore necessary always to use two, and for an extensive crack three may be employed.

All these appliances tend to keep the lips of the crack from separating, but they do not prevent the edges of a deep wide crack from being forced together and thus pinching the sensitive parts. To provide against this injury a slip of hard wood may be fitted into the crack, and then the nails or clips may be more safely drawn tight without fear of injury, and with a better chance of preventing any movement in the edges of the crack. To insert the wood, the crack is converted into a groove nearly as deep as the wall, about three-eights of an inch wide, with straight sides, or better still, with a little greater width at the bottom than at the surface. Into such a groove a piece of wood formed to fit it is gently driven from below and rasped off to fit exactly. Or, softened gutta-percha may be pressed firmly into the space and levelled off when cold.

To "cut out" a sandcrack except for the purpose of refilling it is bad practice as it favours movement and helps to make the defect permanent. To rasp away the horn so that only a thin layer is left is also injurious. No horn should be removed except for the fitting of a plug as above described or, under veterinary direction, for the purpose of giving vent to matter which has formed within the hoof.

In many European countries a shoe is used for toe-cracks which has two clips drawn on the inside border of the shoe at the heels. These clips catch the bars of the hoof and prevent the heels of the foot closing in. The idea is that when the wall at the heels contracts, there is a tendency for the wall at the toe, if separated by a crack, to open. Fig. 85 shows the position of the clips which must be carefully fitted so as to rest on the inside of the bars. Mr. Willis, V.S., has tried these shoes and speaks well of their utility.

When the crack is in the quarters of the foot, it is not the tendency to expansion of the hoof that has to be guarded against. It is the downward motion of the heels that forces open a crack in this position. The farrier provides against this by taking care to have a firm bearing of the shoe on the hoof behind the crack as shown in A figure 82.

=Contracted Feet.= Some diseases of the foot lead to contraction of the hoof, which is most noticeable round the coronet and at the heels. Any long continued lameness which prevents the horse placing the usual weight on the foot may be accompanied by contraction. Constant cutting away of the bars and paring the frog so that it takes no contact with the ground also leads to shrinking in of the heels. By lowering the heels and letting the frog alone many feet will in time widen out to their proper size, but no system of shoeing is so good for contracted feet as the use of tips, which leave the whole back part of the hoof to take direct bearing on the ground.

Many shoes have been invented for forcing open the heels of contracted feet. Some have had a hinge at the toe and a movable screw at the heel. Some have had the bearing-surface at the heels made with a slope outwards, (See Fig. 53, page 74) so that the weight of the horse should constantly tend to force the heels apart. There is no necessity for any of these contrivances. A properly fitted tip (See page 78) will permit the hoof gradually to expand to its healthy size and form.

=Seedy-toe.= This is a condition of the wall usually found at the toe but not uncommon at the quarters. It is not common in hind feet but occurs sometimes. When the shoe is removed a separation is noticed between the sole and the wall, and this separation may extend up the wall nearly to the coronet. As a rule the space so formed is a narrow one, but it may be wide enough to admit three fingers of a man's hand. Probably all seedy toes result from some injury or disease of the coronary band from which the wall grows, and the first appearance is not a cavity but a changed and softened horn, which may be dry and crumbly, or moist and cheesy. The diseased horn may be scraped out and the cavity filled with tar and tow. The wall bounding the cavity should be relieved of all pressure on the shoe, and if a radical cure be desired all the unattached wall should be cut away. This, however, should be done under veterinary guidance.

=Turning in of the Wall.= By this expression, I mean those cases of weak low-heels in which the border of the wall turns inward. Such a form of horn offers no suitable bearing for a shoe, and if submitted to pressure by a shoe gets worse. Too often this condition is treated by paring away the sole within, which increases the deformity. The sole should not be cut but be left as strong as possible. The curled-in border of the wall should be cut down and all bearing taken off the shoe. In one or two shoeings the wall will resume its proper form. When both heels are so affected, and the horse has to remain at work, only one heel must be treated at a time. The extreme point of the heel is never affected, and affords a point for bearing when the border of wall in front of it is cut away so as not to touch the shoe.