Chapter XI

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When the case is a serious one we have ample evidence to show that ostitis exists, and exists in a severe form. The bones become vastly altered in shape, a process of absorption leads to the formation of large, irregular cavities within their substance, and what of the bone is left is rendered hard and ivory-like (condensed) near what was the original centre, while the edges and other portions show often a tendency to become brittle and porous.

Fig. 118 illustrates the effects of a severe ostitis in pedal bones removed from hoofs with laminitis of several weeks' standing.

_(e) Chronic Laminitis_.--The most common complication--or, perhaps, rather we should term it 'sequel'--to acute laminitis is the chronic form of the disease. For this condition we have reserved a separate section of our work. It will be found described in Section B 1 of this chapter.

_Diagnosis and Prognosis_.--One is almost tempted to state that the diagnosis of laminitis offers no difficulty. In the very early stages, however, it may, as we have already indicated, be mistaken for the oncoming of Enteritis, Lymphangitis, or even Pneumonia. The paddling of the feet may help us. If this is absent, however, nothing but a most careful examination, or, if necessary, the withholding of our opinion until the following visit will prevent a blunder being made.

Even when well established, laminitis has been mistaken for paralysis, for tetanus, for rheumatic affections of the loins, or even for some undiscovered affection of the muscles of the arms and chest. This latter is no doubt suggested to the uninitiated by the reluctance the animal shows to move the muscles _apparently_ of that region, and led the older writers to give to the disease its name of 'Chest-founder.' It is only fair to add, however, that these blunders in diagnosis are nearly always committed by persons without a veterinary training.

Thus warned, the veterinary surgeon of average ability should have no difficulty in establishing a distinction between the diseases we have enumerated as likely to be confounded with it, and the one this chapter is describing.

The prognosis in laminitis should, in our opinion, always be guarded. No advice given in a work of this description can be of any real use, for every case must be judged entirely on its merits. The severity of the symptoms, the cause of the attack, the complications, and the idiosyncrasies of the patient, have all to be taken into account. These the veterinarian must be left to judge for himself.

_Treatment_.--The treatment of acute laminitis in its early stage must be based upon the fact that we have to deal with a congested state of the circulatory apparatus of the whole of the keratogenous membrane. This fact was well enough known to the older veterinarians. It is not surprising, therefore, to learn that jugular phlebotomy was at once resorted to as the readiest means of relieving the overcharged vessels of their blood. As a matter of fact, bleeding from the jugular is still advocated by modern authorities. We cannot say, however, that we unhesitatingly recommend it. Mechanically, of course, the removal of a large quantity of blood is bound to result in a lowering of the pressure in the vessels. The effect, however, is but transient. Blood removed in this way is again quickly returned to the vessels so far as its fluid matter is concerned, and the pressure, removed for a time, is again as great as before. With the other and more vital constituents of the blood-stream--namely, the corpuscles--restoration is not so rapid. We have, in fact, a weakened state of the system, in which it is probable it will not so successfully combat the adverse conditions the disease may induce.

With these prefatory remarks, we may advise bleeding under certain conditions. The quantity removed must be moderate (7 to 8 pints), and the pulse and other conditions must show no signs of weakness or collapse.

Local bleeding, either from the toe or the coronet, is also advised. In the former situation the sole is thinned down until a sufficient flow is obtained, while at the coronet scarification is the method adopted. Bleeding locally, however, is far less effectual than the jugular operation. Neither must it be forgotten that wounds in these situations, more particularly at the toe, are extremely liable, especially with the existing poisoned state of the blood-current, to take on a septic character. What might possibly have remained a comparatively simple inflammation is induced by the operation itself to terminate in the more complicated and serious condition of suppuration.

Other means of combating the congested state of the membrane are principally those of local applications. With many veterinary surgeons warm poulticing is still largely advocated and practised. We do not believe in it. Warmth, as a means of removing local congestion, can only be successful when applied _widely_ round the congested area, and so dilating surrounding bloodvessels and lymphatics. Applied to the congested area itself, and to that alone, it is almost worse than useless.

With the foot, both around and below it, a surrounding area is denied us. The only vessels we are able to dilate with the warmth, and so enable them to carry off the fluid from the congested foot, are those in the limb above. That poulticing cannot be successfully there applied is self-evident. Apart from that, it is an open question whether poultices may not do actual harm in inducing suppuration in cases where, probably, it would not otherwise occur.

For these reasons we hold to the opinion that when a local application is determined on it should be a cold one. Various methods of applying cold are in vogue. Cold swabs are perhaps most in favour. They must, however, be _kept_ cold. When a suitable water-course, pond, or other expanse of shallow water is at hand, then the animal may be kept standing therein, or preferably walked about in it. When suitable apparatus is obtainable, a constant stream over each foot from a rubber hosepipe is most beneficial.

Astringent baths, containing solutions of alum, of copper sulphate, of iron sulphate, or of common salt, or composed of a mixture of two or more of the salts mentioned, may also be used with advantage. In addition to the fact that such solutions are for a time below the temperature of simple water, we have the advantage that they have also a more or less antiseptic property.

While on the subject of the relief of the congestion, we must not forget to mention a treatment which we ourselves have practised with considerable success--namely, that of forced exercise. It appears to have been first brought into prominence by Mr. Broad, of Bath, and the two terms 'Forced Exercise and Rocker Shoes' and 'Broad's Treatment' have come to be synonymous.

The Broad shoe is a shoe with a web of quite twice the thickness of the animal's ordinary shoe, and has this web gradually thinned from the toe backwards until at the heels the shoe is at its thinnest (see Fig. 119).

The excessive thickness of the shoe serves two purposes. It allows of the requisite amount of slope being given to the web, and so enables the animal readily to throw himself back on to his heels, a position in which, as we have already indicated, he obtains the greatest ease. It also minimizes to some extent the effects of concussion.

[Illustration: FIG. 119.--SEATED ROCKER BAR SHOE (BROAD'S) FOR TREATMENT OF LAMINITIS.]

With forced exercise, as practised by Mr. Broad, this shoe is first applied, and the animal afterwards made to walk upon soft ground, or even upon the roadway, for a half an hour to an hour and a half three times a day.

For our own part, we consider the shoe to be almost if not quite superfluous, so far as its influence upon the progress of the disease is concerned. We therefore dispense with it, and have the animal exercised in his ordinary shoes. To do this, the patient has sometimes to be severely flogged into taking the first few steps. After that progress gradually becomes easier.

It has been said to be cruel. In so far as we knowingly, and of set purpose, occasion the animal pain, cruel it undoubtedly is; but it is cruelty with an aim that is truly benevolent, and the object of our benevolence is the animal upon whom the cruelty is practised.

One word of advice is needed. The forced exercise must be commenced early. In the later stages, when the stage of congestion has passed from that to the acuter stages of the inflammation and the outpouring of the inflammatory exudate, then forced exercise cannot be safely commenced. The loss of adhesion between the pedal bone and the horny box, which we know to be then existent, negatives its advisability.

By many it is advised to always remove the shoes. From what we have already said, it will be seen that this is not our practice. But one argument in favour of so doing appears to us to carry weight, and that is that 'dropping' of the sole is probably prevented from becoming so marked. That condition, however, is entirely dependent upon the changes occurring within the horny box. It is bound to occur with the animal shod or unshod, and to reach a stage when only contact with the ground prevents its further descent. The complication then sometimes following--namely, penetration of the sole by the bone, is not prevented by having the shoes removed. It may, in fact, be thus rendered more likely.

Internal treatment consists in the exhibition of suitable febrifuges and the administration of a dose of aloes.

With regard to the wisdom of the latter proceeding, opinion seems to be divided. Personally, we hold an open mind concerning it. This much is certain: in many cases of laminitis--those cases which have their origin in overfeeding with an irritating food--there is already a strong predisposition to enteritis. The administration of aloes in this case is extremely apt to induce a fatal super-purgation. Aloes is, again, contra-indicated when the laminitis is a result of excessively long journeys, and the patient is already greatly exhausted. Neither can it be advocated in the laminitis occurring as a sequel to septic metritis or to pneumonia.

On the other hand, when the disease has occurred as a result of long standing in the stable and an overloaded condition of the bowels, or where one full meal of some constipating food, such as whole wheat, pea or bean meal, wheat or barley meal, has occasioned the attack, then a dose of aloes at the commencement of the treatment is productive of good.

Suitable febrifuges are found in potassium nitrate, potassium chlorate, sodium sulphate, or magnesium sulphate, either of which or a mixture of two or more of them, the animal will readily take in his drinking-water.

The administration of sedatives is also indicated. In this connection aconite will be found most useful. More especially in the early stages of the disease, when pain is excessive and the temperature high, will its good effects be noticed. This also the animal will often take in his drinking-water. We have been in the habit of so prescribing the B.P. tincture in 1/2-dram doses three times daily. By its use the temperature is rapidly lowered, the pulse reduced in number and in fulness, and the pain in some instances perceptibly diminished. With others hypodermic injections of morphia and atropine have given equally satisfactory results.

Needless to say, good nursing is a _sine quâ non_. During the first stages of the fever a light and easily digested diet should be allowed--bran-mashes, roots and grass when obtainable, and a carefully regulated supply of water. The animal should be warmly clothed and the box well ventilated, even to the opening of the doors and windows. Only in this way is pneumonia as a sequel sometimes prevented. The patient's comfort should be attended to in providing him with a suitable bed. Anything in the shape of long litter should be avoided. When nothing else is at hand, litter that has already been broken and shortened by previous use is best. With this the box floor should be thickly covered, and matting of the material prevented by constant turning. A good bed for the horse with laminitis is peat-moss mixed with short straw. This, without being dragged into irregular heaps, remains springy and elastic with but little attention. Better than all, however, especially with good weather, is an open crewyard. Here the animal has an abundance of fresh air, has a bed that is always soft, and has plenty of room in which to get up and down with some degree of ease.

Leaving the dietetic and medicinal, we may consider other treatments of laminitis that come more particularly under the heading of operative.

The first matter that here demands our attention is that of allowing the exudate to escape at the sole. If after the expiration of three or four days pain and other symptoms of distress continue, then it may be judged that the inflammatory exudate has made its appearance. Operative measures allowing of its escape, though not giving absolute ease, do undoubtedly relieve the more marked expressions of suffering, and should be at once determined on. To do this completely it is necessary to cast the animal. The sole is then thinned at the toe with the drawing-knife until the sensitive structures are reached. A flow of yellow and sometimes blood-stained discharge is immediately obtained, and the sole itself found to be underrun to a considerable extent. An opening sufficiently large to admit of free drainage (about the size of a half a crown-piece) is made, the wounds antiseptically dressed, and the hobbles removed.

If showing an inclination to do so, the animal should then be allowed to remain and rest. In one instance in which we so operated (a case of laminitis in the hind-feet alone), the relief given was at once manifested. For three days previously the animal had remained standing in agonizing pain. On the fourth he was cast, and the discharge--partly inflammatory exudate, and partly a sanious foetid pus--liberated. The hobbles were removed, and the animal allowed to remain down while our attention was drawn to another case. This attended to, we walked back to the field where, our first patient was lying. His breathing, but a short time before distressedly short and catching, was now so slow and deeply regular that for one brief moment the thought flashed across our mind that he was dead. He was in a _profound_ sleep.

Other operators sometimes give the exudate escape while making the grooves in what is now known as 'Smith's Operation.'

In this operation the hoof is so grooved as to allow of its expansion, so relieving the pressure on the sensitive structures within it. Incidentally, the inflammatory exudate is given exit.

[Illustration: FIG. 120.--DIAGRAM OF HOOF SHOWING THE POSITION OF THE THREE GROOVES MADE IN THE TREATMENT OF LAMINITIS.]

The animal is cast, the shoes removed, and three vertical grooves made in the wall. The first is cut down the centre of toe, extending from the coronet to the ground surface. The second is made to the right of this, and the third to the left, each following the direction of the horn fibres, and each distant about 2 inches from the first (see 1, 2, and 3, Fig. 120).

Each of the grooves must run completely from the coronary margin to the ground surface, and each should be carried through the substance of the horn until the horny laminæ are reached. This done, the underneath surface of the foot is grooved at the white line (see curved groove 4, Fig. 121) in such a manner as to entirely isolate the two pieces of horn _a_ and _b_ from the remainder of the hoof.

Expansion of the horny box is thus brought about, while at the same time the semicircular groove at the toe is made deep enough to allow of the escape of the exudate.

If thought wise by the operator, the two pieces of horn _a_ and _b_ may be isolated, and the exudate given exit by making the fourth groove in the position of the dotted lines in Fig. 120--that is to say, at the lowermost portion of the sensitive structures. By this means the sole will be left intact.

[Illustration: FIG. 121.--LOWER SURFACE OF FOOT SHOWING POSITION OF THE GROOVES MADE IN THE TREATMENT OF LAMINITIS.]

Fuller instruction for making the grooves and the instruments required will be found described in Section C of