Lameness of the Horse Part 13

Anatomy as two posterior ligaments which run each from three points on the sides of the os suffraginis to a piece of fibro cartilage, described as the glenoid cartilage, and attached to the postero-superior edge of the os coronae; between them is the insertion of the inferior sesamoidean ligament.

Etiology and Occurrence.--Everything tending to increase strain upon these ligaments is contributory to possible fibrillary fracture of these structures. Excessive leverage as furnished by long toes, long toe-calks and low heels increases the normal tension on the posterior ligaments of the pastern joint. Faulty conformation, which throws an abnormal strain on these ligaments, is a predisposing cause of inflammation of these structures. Hard pulling upon slippery and rough or frozen roads is a common exciting cause of this injury. The condition is of comparatively frequent occurrence and is seen affecting draft horses frequently, in the hind legs.

Symptomatology.--Lameness is the first manifestation of this affection and weight bearing is painful in direct proportion to the extent of injury present. Volar flexion of the phalanges relieves tension on the parts; therefore, this position is a.s.sumed while the subject is at rest.

When considerable tissue has been ruptured, and the condition is very painful, the foot is held off the ground as in all painful affections of the extremity.

By palpation evidence of pain is discernible, though very little swelling occurs. Pain is increased by manual tension of the parts which is done by grasping the toe of the foot and exerting traction on the flexor apparatus. Care must be taken in executing such manipulations, and it is only by comparison of the affected member with the sound one and noting the difference in the manifestations of discomfort that we may arrive at the proper conclusion.

Some hyperthermia is to be recognized in acute inflammation, by comparing the extremities. In the fore legs, navicular disease is differentiated by noting absence of contraction at the heel. By use of the hoof testers one may recognize evidence of inflammation of the navicular apparatus. In inflammation of the posterior ligaments of the pastern joint, there is also absence of the characteristic stumbling which is seen in navicular disease.

Treatment.--Rest is the first requisite, and in addition every mechanical means possible to change the center of gravity in the phalangeal region, is to be employed. This is best accomplished by shortening the toe and paring the sole at the toe as much as conditions will permit. The heel is raised by means of a shoe with moderately high heel calks.

The iodin-glycerin combination heretofore mentioned may be applied and the parts covered with cotton and bandage. Subjects require from three weeks to several months' rest and must be returned to work carefully, lest the incompletely regenerated tissues suffer injury.

Regeneration of tissue in such cases, as has been pointed out, is slow and sufficient time for complete recovery must be allowed or relapses will occur.

Fracture of the First and Second Phalanges.

Etiology and Occurrence.--Fractures of the first phalanx (suffraginis) occur with respect to frequency, second to pelvic fractures. Often, almost insignificant injuries cause phalangeal fractures. On city streets, horses shod with shoes having long calks get caught in frogs of street railways or by slipping on rails, and phalangeal bones are often broken. The author observed a case of comminuted fracture of both the first and second phalanges (suffraginis and corona) in a polo pony caused by making a sudden turn while in action in a contest on the turf.

Symptomatology.--Fracture of the phalanges is nearly always signalized by lameness, and this is marked during the period of weight bearing.

Lameness is usually intense and where the pathognomonic symptom (crepitation) is not recognized, the intensity of the claudication, when other causes are absent, is indicative of fracture. The subject does not bear weight upon the affected member and where pain is intense, the foot is held in an elevated position and swung back and forth. In hind legs the member is often flexed in abduction and held in this position for several minutes, being rested on the ground only during short intervals.

When compelled to walk, if pain is excruciating, the animal hops with the sound leg, no weight being supported by the fractured member.

When an examination of the subject is possible before the extremity is swollen, crepitation is usually found without great difficulty, except in a subperiosteal break or in some cases of vertical or oblique fracture. Great care is necessary in handling the injured extremity in these cases, and particularly in nervous subjects or in excited animals that have been recently injured in runaways, is it necessary to be gentle in manipulating the extremity, if definite deductions are to be made. As has been mentioned in the chapter on diagnostic principles, if the condition is so painful that the subject does not relax the parts and crepitation is masked, local anesthesia is necessary. An anesthetic solution of cocain or novocain may be applied to the metacarpal or metatarsal nerves and an entirely satisfactory examination is then possible.

Pa.s.sive movement of the phalanges in all directions is practised in order to produce crepitation. When rotation of the parts does not occasion crepitation, gentle flexion and extension may do so. And in many instances, considerable manipulation of the phalanges is necessary before the pathognomonic symptom is to be recognized.

In cases where crepitation is not found and lameness is p.r.o.nounced, out of proportion with other possible existing causes, one may by exclusion of other causes establish a diagnosis of fracture in the course of forty-eight hours. In the meanwhile, support is given the affected member by applying an effective leather splint, so that pain may be diminished. To combat inflammation, a suitable cataplasm may be applied directly to the skin, the extremity bandaged, and the temporary immobilizing appliance may be secured over all. In this manner one may make repeated examinations of the subject, and if slings are used and every other necessary precaution taken to promote comfort for the subject, no harm will result in delaying for several days the application of permanent immobilization--bandages and splints or casts.

In fact, where much swelling exists at the time one is called to treat such cases, it is advisable to delay the application of a permanent dressing or cast until inflammation has somewhat subsided.

Course and Prognosis.--Where conditions are favorable, the nature of the fracture one that will yield to treatment, the subject not aged, and facilities for giving good attention to the affected animal are ample, fractures of the first and second phalanges recover completely in from six weeks to four months. Only simple fractures are considered curable from a practical and economical point of view, excepting in foals, where compound, and even comminuted, fractures may be so handled that animals may eventually become serviceable though blemished.

Age r.e.t.a.r.ds the process of osseous regeneration, but in one instance at the Kansas City Veterinary College, a very aged mare suffering from a multiple fracture of the first phalanx was treated and at the end of sixty days was able to walk into an ambulance. Large exostoses had developed and the subject remained lame, but union of the broken bone took place in a surprisingly prompt and effective manner, when age of the subject and nature of the fracture are considered.

As a rule, one is loath to recommend treatment, even in a simple transverse fracture of the first phalanx, in animals ten years of age or older. The conditions which exist in any given locality that regulate the expense of caring for an animal during the period of treatment, especially influence the course to be pursued in treating fractures.

Treatment.--For permanent immobilization of the phalanges in fracture, materials which might adapt themselves to the irregular contour of the member and at the same time contribute sufficient rigidity to the parts without doing injury to the soft structures, would const.i.tute ideal means of treatment; but no such materials have yet been devised, and opinions are various as to the most efficient and practical method to employ.

After the fetlock has been shorn of hair and the ergot trimmed, the skin is thoroughly cleansed and allowed to dry. Several thin layers of long fiber cotton are then wrapped around the extremity--enough to pad well the member--and this is retained in position with a wide bandage. Gauze bandages are preferable to heavier bandages of cotton fabric because they are somewhat more elastic and yield to the irregular contour of the parts to a better advantage. Layers of three inch gauze bandages, which are soaked with a cold starch paste are wound about the extremity.

Strips of leather that are flexible and not more than an inch in width are placed in a vertical position around the leg and these are also covered with the starch and securely held in position with the bandages.

In this way, one is able to provide a sufficient degree of rigidity and at the same time, where the cast is carefully applied, little if any injury is done the skin. Such a cast is not difficult to remove and is so inexpensive that it may be removed and reapplied at any time it should be thought preferable to do so. Of course, this does not const.i.tute an effective means of support if the parts are to be frequently and thoroughly soaked with water, but animals undergoing this sort of treatment are usually kept sheltered.

The same after-care is necessary in such cases as is given in fractures of other bones. Two months after the injury has been done, the application of a blistering ointment to the entire region is of benefit.

Results.--Much depends on the nature of fractures as to the success one may attain in approximating the parts of a broken bone, and in some cases of oblique fracture for instance, complete recovery is impossible, despite the most skillful and painstaking attention given. On the other hand, cases of simple transverse fractures make perfect recoveries in some instances. All fractures are serious, and in every instance the pract.i.tioner would best be careful to impress his client with the many difficulties which usually attend the treatment of fracture in horses.

Tendinitis.

Inflammation of the Flexor Tendons.

One of the most common causes of lameness in light harness and saddle horses is tendinitis, and because of the character of the structure of tendons and because of their function, an active inflammation of these parts is always serious.

Being almost inelastic and not well supplied with blood, tendinous tissue is slowly regenerated, and so much time is required for complete recovery to take place in tendinitis, that affected animals seldom fully recover before they are in service or vigorously exercising at will. As a result, complete recovery is delayed or prevented.

The extensor tendons, because of the nature of their function, are very seldom strained; they are often bruised and occasionally divided, but unlike this condition in the flexors, tendinitis of the extensors is of rare occurrence.

For a concise discussion of this subject the most practical cla.s.sification is one made on a chronological basis and we may then consider tendinitis as _acute_ and _chronic_.

ACUTE TENDINITIS.

Etiology and Occurrence.--Causes of tendinitis, as in almost all diseases, may be considered under the heads of predisposing and exciting. Among the predisposing causes of tendinitis may be mentioned, faulty conformation. Everything which has to do with increasing the strain upon tendons adds to the probability of their being over-taxed.

Long, sloping, pastern bones; disproportionate development of parts, such as a heavy body and small, weak tendons and long hoofs, are the princ.i.p.al factors which usually predispose to tendinous sprains.

Degenerative changes which take place in tendons following const.i.tutional diseases such as influenza may also be cla.s.sed as a predisposing cause.

Excessive strain when put upon tendons in any possible manner, such as is occasioned in running and jumping; making missteps and catching up the weight of the body with one foot, when the force thus thrown upon the supporting structure is great because of momentum gained at a rapid pace, are exciting causes of tendinitis.

Symptomatology.--In all cases of acute tendinitis there is presented a characteristic att.i.tude by the subject. Volar flexion in a sufficient degree to relax the inflamed structures is always evident. The foot may be rested on the toe or placed slightly in advance of the one supporting weight, but the fetlock is always thrown forward. More or less swelling of the inflamed tendons is present. Where the deep flexor (perforans) is involved swelling is marked and with swelling there is present the other symptoms of inflammation--heat and supersensitiveness.

In manipulating tendons for the purpose of detecting supersensitiveness, care must be taken so that no false conclusion be drawn, because of the aversion many horses have to submitting to palpation of the tendons even when they are in a normal condition.

Supporting-leg-lameness is present and varies in degree with the intensity of the pain caused by weight bearing. In many instances, as soon as the subject has traveled a considerable distance, lameness diminishes or discontinues. As soon as the affected animal is permitted to stand long enough to "cool out" there is a return of the lameness, which is then marked.

No difficulty is encountered in making a practical diagnosis in tendinitis; that is, one may fail to readily recognize the extent of the involvement as it affects the superficial flexor tendon, for instance, but this has no practical bearing on the prognosis and treatment, when existing inflammation of the deep flexor is recognized.

The course of each tendon is readily outlined by palpation; all parts are easily manipulated; and with experience one may readily recognize the extent and degree of the inflammation.

Treatment.--In some cases of acute tendinitis, pain is intense and the application of cold packs during this stage is very beneficial in that pain is controlled and inflammation subsides. The extremity may be bandaged with a liberal quant.i.ty of absorbent cotton or with woolen material. Ice water is then poured around the bandaged member every fifteen minutes and this should be continued for about forty-eight hours. In some cases this treatment is not necessary for more than twelve hours; at the end of this length of time, pain has subsided and the acute stage of inflammation has pa.s.sed or its intensity has been diminished.

Following the application of cold packs, the use of a poultice such as some of the sterile, medicated muds, is of marked benefit. The author has made use of tincture of iodin and glycerin in the proportion of one part of iodin to seven parts glycerin, with very satisfactory results.

This combination is hygroscopic, anodyne and antiseptic and is easily applied. A liberal quant.i.ty is directly applied all around the affected tendons and the leg covered with a heavy layer of cotton, and this is snugly held in position with bandages. The application may be used once or twice daily, or if it is thought necessary, an attendant may pour a quant.i.ty of the iodized-glycerin around the leg and under the bandage once daily without removing the cotton and bandage. Needless to say, absolute rest is imperative.

When all evidence of acute inflammation has subsided vesication is indicated. At this stage walking exercise is beneficial and the subject may be allowed the freedom of a paddock.

Some pract.i.tioners are partial to the use of the actual cautery in these cases, but it is doubtful if it is necessary to produce such a great degree of counter-irritation in cases where the subject is suffering the first attack of tendinitis.

As has been indicated, ample time should be allowed for recovery and depending upon conditions, it takes from three weeks to six months for complete recovery to become established.

Chronic Tendinitis and Contraction of the Flexor Tendons.

Etiology and Occurrence.--Acute inflammation of the flexor tendons may result in chronic tendinitis. Recurrent attacks in cases where insufficient time is allowed for complete recovery to result, is followed by chronic inflammation and hypertrophy of the tendons. Again, in subjects where conformation is faulty, no amount of care will be sufficient to prevent a recurrence of the inflammation and the condition must become chronic.

Symptomatology.--On visual examination of the subject at rest, one may note the hypertrophied condition of the affected tendons. Their transverse diameter is usually perceptibly increased and in many cases, there is an increase in the antero-posterior diameter. The latter condition causes a bulging of the tendon that is so noticeable, because of the convexity thus formed, it is commonly known as "bowed tendon."

[Ill.u.s.tration: Fig. 20--Contraction of the superficial digital flexor tendon (perforatus) of the right hind leg, due to tendinitis.]