Part 75

A very slight change is often sufficient to effect this result. At the same time the offending foot should be so shod that the shoe may set well under the hoof at the point responsible for the injury. The shoe should be reset every three or four weeks.

When the cause has been removed, cold-water bandages to the injured parts will soon remove the soreness and swelling, especially in recent cases. If, however, the fetlock has become calloused from long-continued bruising, a Spanish-fly blister over the parts, repeated in two or three weeks if necessary, will aid in reducing the leg to its natural condition.

KNUCKLING, OR COCKED ANKLES.

Knuckling is a partial dislocation of the fetlock joint, in which the relative position of the pastern bone to the cannon and coronet bones is changed, the pastern becoming more nearly perpendicular, with the lower end of the cannon bone resting behind the center line of the large pastern, while the lower end of this bone rests behind the center line of the coronet. While knuckling is not always an unsoundness, it nevertheless predisposes to stumbling and to fracture of the pastern.

Causes.--Young foals are quite subject to this condition, but in the great majority of cases it is only temporary. It is largely due to the fact that before birth the legs were flexed, and time is required after birth for the ligaments, tendons, and muscles to adapt themselves to the function of sustaining the weight of the body.

As they grow old, horses with erect pasterns are very prone to knuckle, especially in the hind legs. All kinds of heavy work, particularly in hilly districts, and fast work on hard race tracks or roads are exciting causes of knuckling. It is also commonly seen as an accompaniment of that faulty conformation called clubfoot, in which the toe of the wall is perpendicular and short, and the heels high--a condition most often seen in the mule, especially in the hind feet.

ANATOMY OF FOOT.]

ANATOMY OF FOOT.]

ANATOMY AND DISEASES OF THE FOOT.]

SOUND AND CONTRACTED FEET.]

Lastly, knuckling is produced by disease of the suspensory ligament or of the flexor tendons, whereby they are shortened, and by disease of the fetlock joints. (See p. 372.)

Treatment.--In young foals no treatment is necessary, unless there is some deformity present, since the legs straighten up without interference in the course of a few weeks. When knuckling has commenced, the indications are to relieve the tendons and ligaments by proper shoeing. The foot is to be prepared for the shoe by shortening the toe as much as possible, leaving the heels high; or if the foot is prepared in the usual way the shoe should be thin in front, with thick heels or high calks. For the hind feet a long-heeled shoe with calks seems to do best. Of course, when possible, the causes of knuckling are to be removed; since this can not always be done, however, the time may come when the patient can no longer perform any service, particularly in those cases in which both fore legs are affected, and it becomes necessary either to destroy the animal or obtain relief by surgical interference. In such cases the tendons between the fetlock and knee may be divided for the purpose of obtaining temporary relief. Firing and blistering the parts responsible for the knuckling may, in some instances, effect a cure; but a consideration of these measures belongs properly to the treatment of the disease in which knuckling appears simply as a sequel.

WINDGALL.

Joints and tendons are furnished with sacs containing a lubricating fluid called synovia. When these sacs are overdistended by reason of an excessive secretion of synovia, they are called windgalls. They form a soft, puffy tumor about the size of a hickory nut, and are most often found in the fore leg, at the upper part of the fetlock joint, between the tendon and the shin bone. When they develop in the hind leg it is not unusual to see them reach the size of a walnut. Occasionally they appear in front of the fetlock on the border of the tendon. The majority of horses are not subject to them after colt-hood has passed. (See also p. 355.)

Causes.--Windgalls are often seen in young, overgrown horses, in which the body seems to have outgrown the ability of the joints to sustain the weight. In cart and other horses used to hard work, in trotters with excessive knee action, in hurdle racers and hunters, and in most cow ponies there is a predisposition to windgalls. Street-car horses and others used to start heavy loads on slippery streets are the ones most liable to develop windgalls in the hind legs.

Symptoms.--The tumor is more or less firm and tense when the foot is on the ground, but is soft and compressible when the foot is off the ground. In old horses windgalls generally develop slowly and cause no inconvenience. If they are caused by excessive tension of the joint the tumor develops rapidly, is tense, hot, and painful, and the animal is exceedingly lame. The patient stands with the joint flexed, and walks with short steps, the toe only being placed on the ground. When the tumor is large and situated upon the inside of the leg it may be injured by interfering, causing stumbling and inflammation of the sac. Rest generally causes the tumor to diminish in size, only to fill up again after renewed labor. In old cases the tumors are hardened, and may become converted into bone by a deposit of the lime salts.

Treatment.--The large, puffy joints of suckling colts, as a rule, require no treatment, for as the animal grows older the parts clean up and after a time the swelling entirely disappears.

When the trouble is from an injury, complete rest is to be obtained by the use of slings and a high-heeled shoe. Cold-water douches should be used once or twice a day, followed by cold-water bandages, until the fever has subsided and the soreness is largely removed, when a blister is to be applied.

In old windgalls, which cause more or less stiffness, some relief may be had by the use of cold-compress bandages, elastic boots, or the red iodid of mercury blisters. Opening the sacs, as recommended by some authors, is of doubtful utility, and should be adopted only by the surgeon capable of treating the wound he has made. Enforced rest until complete recovery is effected should always be insisted upon, since a too early return to work is sure to be followed by relapse.

SPRAIN OF THE FETLOCK.

Sprain of the fetlock joint is most common in the fore legs, and, as a rule, affects but one at a time. Horses doing fast work, as trotters, runners, steeplechasers, hunters, cow ponies, and those that interfere, are particularly liable to this injury.

Causes.--Horses knuckling at the fetlock, and all those with diseases which impair the powers of locomotion, such as navicular disease, contracted heels, sidebones, chronic laminitis, etc., are predisposed to sprains of the fetlock. It generally happens from a misstep, stumbling, or slipping, which results in the joint being extended or flexed to excess. The same result may happen where the foot is caught in a rut, a hole in a bridge, or in a car track, and the animal falls or struggles violently. Direct blows and punctured wounds may also set up inflammation of the joint.

Symptoms.--The symptoms of sprain of the fetlock vary with the severity of the injury. If slight, there may be no lameness, but simply a little soreness, especially when the foot strikes on uneven ground and the joint is twisted a little. In more severe cases the joint swells, is hot and puffy, and the lameness may be so intense as to compel the animal to hobble on three legs. While at rest the leg is flexed at the joint affected, and the toe rests on the ground.

Treatment.--If the injury is slight, cold-water bandages and a few days' rest are sufficient to effect recovery. When there is an intense lameness, swelling, etc., the leg should be placed under a constant stream of cold water, as described in the treatment for quittor. When the inflammation has subsided, a blister to the joint should be applied.

In some cases, especially in old horses long accustomed to fast work, the ligaments of the joints are ruptured, in whole or in part, and the lameness may last a long time. In these cases the joint should be kept completely at rest; this condition is best obtained by the application of plaster of Paris bandages, as in cases of fracture. As a rule, patients take kindly to this bandage, and, while wearing it, may be given the freedom of a roomy box or yard. If they are disposed to tear it off, or if sufficient rest can not otherwise be obtained, the patient must be kept in slings.

In the majority of instances the plaster bandage should remain on from two to four weeks. If the lameness returns when the bandage is removed, a new one should be put on. The swellings which always remains after the other evidences of the disease have disappeared, may be largely dissipated and the joint strengthened by the rise of the firing iron and blisters.

A joint once injured by a severe sprain never entirely regains its original strength, and is ever after particularly liable to a repetition of the injury.

RUPTURE OF THE SUSPENSORY LIGAMENT.