[Footnote A: Properly speaking, we have in the foot of the horse but _one_

joint--namely, the corono-pedal articulation.

Although not a joint in the strict sense of the word, we, nevertheless,

intend here to consider the navicular bursa as such. In this apparatus,

although we have no articular cartilage proper, and no apposition of bone

to bone, we still have a large synovial cavity, and in close proximity to

it bone. We may, in fact, and do get in it exactly similar changes to those

termed 'synovitis' and 'arthritis' elsewhere. Therefore, we include the

changes occurring in it in this chapter, and hence the plural use of the

word to which this note refers.]

A. SYNOVITIS.

_Definition_.--By the term 'synovitis' is indicated an inflammation of the

synovial membrane. It may be either (_a_) _Simple_ or _Acute_, or it may be

(_b_) _Purulent_ or _Suppurative_.

In the simple form there is little or no tendency for the affection to

implicate the other structures of the joint, whereas in the suppurative

form the joint capsule, the ligaments, and the bones soon come to

participate in the diseased processes, giving us a condition which we shall

afterwards describe as acute arthritis.

(_a_) SIMPLE SYNOVITIS.

1. _Acute--(Causes)_.--Simple or acute synovitis is nearly always brought

about by injury to the joint--by blows or bruises, or by sprains of the

ligaments. At other times it occurs without ascertainable cause, and is

then put down to the influence of cold, or to poisonous materials (as, for

example, that of rheumatism) circulating in the blood-stream.

_Pathology_.--Uncomplicated acute synovitis never causes death. The

pathological changes in connection with it have therefore been studied in

cases purposely induced, and the animal afterwards slaughtered. It is then

found that, as in inflammation elsewhere, the synovial membrane is showing

the usual inflammatory phenomena--that it is thick and swollen as a result

of the inflammatory hyperæmia and commencing exudation. Later, the synovial

fluid becomes increased in quantity, is thin and serous, and after a time

is seen to be mixed with the inflammatory exudation poured into it. We then

find that it has lost its clear appearance, has become thick and muddy, and

has floating in it flakes of fibrin.

If the case progresses favourably these materials are soon absorbed and

resolution occurs. In rarer cases the thickening and congestion of the

membrane increases, and the articular capsule becomes so distended with the

increased synovia and accumulated inflammatory discharges that a kind

of chemosis occurs. In other words, there oozes through, without actual

rupture of the membrane, a thin, blood-stained, and purulent-looking

discharge.

It is an important point to note that in cases of synovitis the fringes of

the synovial membrane become swollen and blood-injected, forming noticeable

red elevations at the margins of the cartilages. It is then that the

diseased condition soon spreads and runs into arthritis.

Further, it is important, especially with regard to the question of the

degree of pain and lameness likely to be caused, to note that often

granulations are thrown out upon the looser folds of the membrane. As

these increase in size they come to form fringed and villous membranous

projections inserting themselves between the bones forming the

articulation. In such cases there is no doubt that the intense pain

sometimes observed in these cases is due to pinching of these prolongations

of the synovial membrane by the opposing bones of the joint.

_Symptoms and Diagnosis_.--Acute synovitis of a joint leads to heat of the

parts, pain, distension of the capsule, and, where the joint may be easily

felt, fluctuation. In the articulation with which we are dealing, however,

these last two symptoms are not easily detected, for the surrounding

structures--namely, the lateral and other ligaments of the joint, the

extensor pedis tendon in front, and the perforans behind, together with the

dense and comparatively unyielding nature of the skin of the parts--are

such as to prevent distension and fluctuation becoming marked to a visible

extent. We are able to diagnose the case as one of foot lameness, and, with

a history of a severe blow or other injury, are able to assume that this

condition, perhaps attended with periostitis, is in existence.

When other symptoms present themselves diagnosis may be more certain. The

animal becomes slightly fevered, throbbing pains in the joint manifest

themselves by irregular pawing movements on the part of the patient. The

animal comes out from the stable stiff, even dead-lame, and the limb is

carried with the lower joints semiflexed. The breathing is hurried and the

pulse firm and frequent, while in a bad case patchy perspiration breaks out

at intervals on various parts of the body. If with this we get a puffy and

tender swelling in the hollow of the heel, our diagnosis may be certain at

any rate as to the existence of joint trouble, although, from reasons we

have given, we may not be able to mark its exact nature.

2. _Chronic_.--Simple synovitis may in many instances become chronic. In

this case we have simply a pouring into the synovial capsule of serous

fluid, and with it an increased quantity of synovia--this time with an

absence of the usual inflammatory phenomena. Beyond the swelling of the

capsule there is little to be noticed. The joint becomes perhaps a little

weaker, but pain or tenderness and heat are entirely absent. Such a

condition, by reason of the natural rigidity of the parts, is not to be

observed in the foot, although at times it must most certainly occur.

Examples of such a condition are to be found in bog-spavin, in hygroma of

the stifle, and sometimes in the fetlock. From a study of these, we know

that they may be induced by frequent attacks of acute synovitis, from

repeated slight injuries or bruises, or from strains to the ligaments of

the joint; or that they may be chronic from the outset. We know, too, that

in such cases the synovial membrane becomes thickened, and that in places

it may have extended somewhat over the edges of the articular cartilages.

It is only fair to suppose that such changes occur also in the pedal

articulation. In that case we may take it for certain that the natural

rigidity of the surrounding structures has the effect of pushing the

thickened membrane further between the bones of the joint than occurs in a

like condition elsewhere, leading, of course, to a lameness that is marked

in degree but occult as to cause.

In our minds there is no doubt that many of the occult and chronic forms of

foot-lameness we meet with in practice are in this way to be accounted for.

We may, in fact, explain them by suggesting either a chronic synovitis

alone, or a synovitis complicated with periostitis.

_Treatment of Synovitis_.--If a joint has been injured, as we have

suggested, by slight blows or other causes--in other words, if the injury

is subcutaneous, and no wound is in existence--then there is no treatment

which offers better results than does the continued application of cold.

At the same time, the animal should be slung, or, if non-excitable and

inclined to rest, allowed at intervals to lie on a thick and comfortable

straw bed, the cold fomentations during such intervals being discontinued.

When the case is a marked one and the animal valuable, benefit will be

derived from the application of crushed ice.

The animal's condition must be watched, and the case helped as far as is

possible by the administration of a mild dose of physic, by saline drinks,

and, when necessary, by the giving of small but repeated doses of Fleming's

tincture of Aconite in order to relieve the pain. In a chronic case the

repeated application of a blister is indicated.

(b) PURULENT OR SUPPURATIVE SYNOVITIS.

In this condition we have synovitis complicated by the presence of pus.

Unlike the simple form, it shows a marked disposition to spread, and

quickly involves the surrounding structures. Very soon the ligaments of

the joint, the periosteum, the articular cartilages, and the bones are

implicated. This, of course, constitutes a condition of acute purulent

arthritis. Under that heading, therefore, the condition will be later

discussed.

B. ARTHRITIS.

(a) SIMPLE OR SEROUS ARTHRITIS.

With an attack of simple synovitis it may be always assumed that the

changes commenced in the synovial membrane, communicate themselves more

or less readily to the surrounding tissues, and are not confined to the

synovial membrane alone. We may thus have the inflammatory phenomena

asserting themselves in the surrounding ligaments, in the periosteum, in

the bone, and in the articular cartilages. It depends, in fact, upon the

severity of our case whether we call it synovitis or arthritis. The two

conditions merge so the one into the other that no hard-and-fast rule

may be laid down whereby they may with certainty be differentiated. Such

symptoms, therefore, as we have given for synovitis may be also read as

indicating a condition of simple arthritis. The course of the case will be

very similar, and the treatment to be followed identical with that just

given.

(b) ACUTE ARTHRITIS.

_Causes_.--An attack of acute arthritis may commence with the affection of

the synovial membrane, and spread from that to the other structures. In

other cases the disease of the synovial membrane, and after it the disease

of the joint, may be secondary to diseases commencing in the structures

around the joint. This affection may therefore follow on a case of acute

coronitis, a case of suppurating corn, a case of quittor, a severe case of

tread, or may attend a case of laminitis.

_Symptoms_.--In our cases we get very little beyond a magnification of such

symptoms as we have described under acute synovitis. The heat and the pain

is perhaps greater, and the lameness more marked. It is rather to the

constitutional disturbance we must look, however, for a confirmation of our

opinion that arthritis is in existence. This is always severe, and of

an acute febrile nature. The pulse is fast, thin, and thready, the

respirations enormously increased, and the temperature high. The appetite

is in abeyance, the animal quickly becomes what is termed 'tucked-up,' or

greyhound-like, in the body, and patchy perspirations break out about him.

The limb is held with the joints all semiflexed, and severe and intense

throbbing pains are indicated by the frequent pawing movements the animal

makes in the air. Manipulation of the foot is resented, and the agonizing

intensity of the pain so caused is shown by the drawn and haggard

appearance of the eyes.

In a favourable case the symptoms from now onwards may gradually subside.

The appetite returns, the breathing and other signs of disturbance show a

return to the normal, weight is placed on the limb, and resolution slowly

but surely takes place. In many of these, our favourable cases, however,

resolution is incomplete, and recovery only takes place at the expense of

anchylosis of the joint, a condition we shall refer to later.

In unfavourable cases, and these unfortunately are only too common, the

condition terminates in suppuration.

(c) PURULENT OR SUPPURATIVE ARTHRITIS.

_Definition_.--By this term we indicate an arthritis complicated by the

formation of pus within the joint.

_Causes_.--The organisms of pus may infect the joint by extension of a

suppurating process from without. For example, in the case of a suppurating

corn, in quittor, in tread, or in the case of a suppurating wound caused

by a prick, the pus formed may in many instances be very near the capsular

ligament of the articulation. Under such circumstances, unless there is a

free and unhindered flow of the pus from an outside opening, inroads will

be made by it upon the thin capsule. The latter is quickly penetrated, and

pus is admitted to the interior of the joint.

In other cases infection of the joint may proceed from within, from a

poisoned state of the blood-stream. The condition occurs, for instance,

in bad attacks of laminitis. We ourselves, too, have seen two cases where

suppuration of the pedal articulation occurred in the septic pyæmia of

foals, a disease known commonly as 'joint-ill,' and characterized by an

infected state of the circulation. Cases have also come under our notice

where this condition has resulted from slight injuries in the region of

the insertion of the extensor pedis inflicted by the animal himself when

galloping away.

Perhaps, however, the most common cause of suppurative arthritis in the

foot is direct penetration of the articulation in the case of pricks.

The penetrating object is nearly always dirty--bacterially dirty, at any

rate--and suppuration only too readily commences. Even should such a wound

be inflicted by an aseptic body, infection would quickly ensue as a result

of the wound gathering dirt from the ground, or even from admission to the

joint of impure and bacilli-laden air.

_Symptoms and Diagnosis_.--This is one of the most serious conditions we

are called upon to face when dealing with diseases of the foot, for in many

cases it quickly ends in exhaustion and death of the patient, while in even

the most favourable cases nothing better than a condition of complete and

bony anchylosis is to be expected. The owner, therefore, should be warned

accordingly.

As in the other joint affections, so here, we get all the symptoms of

acute febrile constitutional disturbance. The pulse, the temperature,

the respirations, and the general haggard, 'tucked-up,' and distressed

appearances of the animal all tell too plain a tale. Our patient is in

constant pain, and the seat of the trouble is clearly enough shown by the

constant pawing movements of the affected foot. If he has room to get up

and down in comfort the animal adopts for long periods at a stretch the

recumbent position, and is not upon his legs long enough to take the

necessary amount of food to keep him going. Even when down, it is plain to

see that the animal is not at rest. The pawing movement is still maintained

with the foot, and every now and again the eyes are opened and the headed

lifted to give a troubled look round. The appetite, too, is capricious, and

in many cases almost entirely lost.

In some slight degree the condition is less to be feared in a fore than in

a hind foot--that is, so far as absolutely fatal results are concerned.

With the condition confined to one fore-foot, the animal is able to get up

and down with a moderate degree of comfort. At intervals, therefore, he

rises to take nourishment, and as soon as his wants are satisfied again

lies down.

With the disease in a hind-foot matters are not taken so comfortably. The

patient finds that with each day's increasing weakness the difficulty that

at first he had to raise himself with only one sound hind-foot becomes

enormously increased. The consequence is that he fears to go down, and the

standing position is maintained until sheer weakness overcomes him, and he

goes down, not to rise again without assistance.

If judiciously attended he is, of course, put in slings before this stage

is reached; but there are instances, as in the case of a cart-mare heavy

with foal, where the use of slings is most decidedly contra-indicated.

If doubt before existed as to the nature of the case, it is at a later

stage dispelled by the appearance, generally in the hollow of the heel, of

a hot and painful swelling. This at first is hard, but later fluctuates.

Finally it breaks at one or more spots, and there exudes from the opening

or openings a purulent and oftentimes sanious discharge, which coagulates

about each fistula after the manner of ordinary synovia.

With the discharge of the abscess contents there is some slight improvement

in the symptoms. Here, with a suitable treatment, and with a patient of a

particularly robust constitution, the case appears to turn, and slowly but

surely progresses towards the only end we can hope for--namely, a more or

less painless anchylosis of the articulation.

In less favourable cases the purulent discharge continues, and (always a

bad sign) becomes more or less chocolate-like in colour, distinctly thin,

and stinking. The diseased process spreads until the ligaments of the

joint, both by reason of their infiltration with the inflammatory

discharges, and also on account of the ravages made on them by the invading

pus, either greatly stretch or altogether rupture.

The joint, after its ligaments have been destroyed in this manner, is

loosened, and the bones are now freely movable. Their manipulation gives

to the touch a sickening, grating sound--in other words, we have crepitus.

This, of course, indicates that the articular cartilages have become

greatly eroded by the inflammatory process, and so left what we may term

'raw' surfaces of bone to rub together. When the animal is put to the walk

the toe of the foot is elevated, and the extreme mobility of the foot gives

one the idea of fracture. With every step there is a peculiar sucking

noise, comparable to that of a foot moving in a boot of water, and

putrescent matter is squeezed from every opening each time the foot is put

to the ground. Although we have seen cases even advanced thus far recover,

it is questionable whether it is now wise to attempt to prolong life.

Slaughter is far more humane, and, in our opinion, except with a valuable

brood animal, more economical.

If the animal is allowed to linger, other symptoms will nearly always

present themselves before death occurs. Whether in slings or not, a careful

watch should be kept upon the sound limb. For some time the patient stands

upon it incessantly, but sooner or later it happens that a farther visit

show us the animal standing with full weight on the diseased foot, and

making painful pawing movements with what before was the sound. We

immediately jump to the conclusion 'laminitis.' And so it is, but it is a

laminitis brought about by pyæmia. This is indicated by the swollen and

oedematous nature of the lymphatics of the limb. Plainly enough they

indicate the road by which the poison has travelled. It is in this way: Pus

and putrefactive organisms have gained entrance to the lymphatics of

the original diseased limb. From these they have rapidly gained the

blood-stream and set up infection elsewhere. In this particular instance it

is demonstrated by the laminitis and lymphangitis of the previously sound

limb. With the poison thus circulating in the blood-stream, we often

also get spots of infection commenced in one or other of the more vital

organs--notably the lungs or the kidneys. The end of our case is then

either a gangrenous pneumonia or complications induced by a condition of

widespread pyæmia.

With the animal in slings there are one or two other symptoms that call

for attention. In many cases, especially with animals of a lymphatic and

indolent nature, the use made of them is inordinate. The patient rests

so continually in them that alarming swellings commence to make their

appearance about the rectum, or in the case of a mare about the vulva. The

animal must then be let down at regular intervals and again raised when

rest is obtained.

A more alarming symptom still is when the animal, instead of resting in the

slings by his buttocks, casts his weight bodily into the belly-rest and

hangs with a heavy head into the head-stall. This indicates complete

exhaustion and a wish for death. Matters should therefore be explained to

the owner, and his consent obtained for immediate destruction.

_Pathology_.--The pathological changes occurring in suppurative arthritis

we shall pass over briefly. It is almost sufficient, in fact, to say that

the whole of the joint becomes completely disorganized.

The synovial membrane becomes so tremendously thickened and injected as to

be scarcely recognisable as such, the thickening in the later stages

being due to large growths of granulation tissue which entirely alter the

appearance of the membrane as we know it normally. In the early stages

the contents of the joint are composed of thin pus and synovia. Later,

as destruction of the synovial membrane proceeds, the flow of synovia is

stopped, while the pus formation goes on until finally nothing but pus and

dead tissue products fill the cavity.

If the suppurative process has commenced from within, the pus that is

formed is, as a rule, thick and creamy, comparatively unstained, and free

from marked odour. If, on the other hand, air has gained access to the

joint, or the suppurative process has started from the materials introduced

by a foreign body, the joint contents are thin, blood-stained, and

stinking.

The inflammatory changes in the joint soon spread to the ligaments, and to

the soft structures in contact with them. This means that the ligaments

become infiltrated with inflammatory exudate, that the fibrous bundles

composing them become separated, and that the ligaments are weakened and

easily stretched. As a consequence, a certain amount of displacement or

dislocation of the bones is allowed.

In like manner the inflammatory changes keep spreading until we have the

periosteum next the ends of the bones affected. The periostitis thus set

up invariably takes the osteoplastic form, and as a result of this we have

growths of new bone in the near neighbourhood of the joint. It is in the

later stages of the disease--that is, when the pus has been evacuated and

reparative changes commenced--that this osteoplastic periostitis is most

marked, and it plays a large part in bringing about the condition of

anchylosis, which we shall afterwards describe.

Grave changes also occur in the articular cartilages. They quickly lose

their peculiar glistening polish, their semitransparency is lost, and the

natural tint of a pearl-like blue gives way to a dirty yellow. Later this

is followed by erosion of the cartilages at such points as they happen to

be in greatest contact. The ends of the bones are thus exposed, and their

medullary cavities exposed to infection. As a result we get in them the

changes we have already described under Ostitis.

_Treatment_--_(a) Preventive_.--Seeing that many of these cases have their

starting-point in stabs or penetrating wounds of the sole, we shall be

concerned first with a consideration of the correct treatment to be adopted

when we know the wound to have reached the articulation.

Only too frequently the treatment practised is that of poulticing. In other

portions of this work we have pointed out the advantages that a continued

antiseptic bathing has over the application of a poultice, the greater

readiness with which the solution comes into contact with the deeper parts

of the wound, and the far greater chance there is of maintaining water in

an antiseptic condition than there is of keeping a poultice in the same

state. There is no doubt, that in this case also, the cold or warm

antiseptic bath is to be preferred to the poultice. It is questionable,

however, whether even the bath is sufficient for our purpose here. We have

in this case a deep punctured wound, and a wound that in every probability

is infected with the organisms of pus or of putrefaction. It is a wound,

moreover, which is likely to impede the thorough access to it of the

solution in which the foot is fomented, on account of the flakes of

coagulated fibrin which fill it.

The most rational treatment, therefore, if we get to the case early enough,

is to irrigate the wound freely with a solution of carbolic acid in water

(1 in 20), or with a solution of perchloride of mercury (1 in 1,000),

injected by means of a glass syringe, or the pattern of syringe devised for

quittor. This injecting should be done thoroughly, and by that we mean that

several syringefuls of the solution should be injected, the joint after

each injection being manipulated so as to distribute the solution as far as

possible over it. When this is done the opening in the sole may be plugged

with a little perchloride of mercury, or, better still, with a little piece

of tow saturated with a concentrated solution of perchloride of mercury

or a solution of iodoform in alcohol and an antiseptic pad of tow or lint

placed over all. The foot should then be bandaged and encased in a boot or

sacking protective. The bandage should be removed daily and the antiseptic

pad changed. At each visit the animal's condition must be carefully

noted. So long as constitutional disturbance is slight, the foot appears

comfortable, is free from marked heat and tenderness, and pawing movements

are absent, and so long as the discharge on the pad appears non-purulent,

free from marked odour, and small in quantity, then this dressing may be

persisted in.

This treatment of open joint, preventive as it is of arthritis, is also

indicated in the case of open navicular bursa. In several instances we have

practised this treatment for the dressing of wounds implicating the bursæ

of tendons and the capsules of joints. It is also spoken of favourably by

Mr. C.H. Flynn in the _American Veterinary Review_ for June, 1888, whose

treatment is as follows: 'Place the patient in a clean, well-ventilated,

and drained stable. Have all the litter removed, and insist on the stall

being kept clean. Either place the animal in slings, or tie the head so as

to prevent lying down. Clip the hair and cleanse the parts well. He prefers

the corrosive sublimate solution (1 in 1,000). Should the wound be of two

or more days' standing, inject the joint with the corrosive sublimate

solution. Now dry the parts with a clean towel and sprinkle the wound with

iodoform. Over this place a thick layer of absorbent cotton-wool, filled

with iodoform, bandage securely, and keep the patient on a moderate diet,

preserving the utmost quietude possible. Should the bandage remain in

position and the animal free from pain, leave the bandage and dressing in

place from five days to a week. Then change it, and should the discharge

be little, do not disturb it, but renew the iodoform and cotton dressing,

leaving it on for another week.'

Other treatments for the same condition are practised, in which the wound

is dusted with powdered iodoform, with potassium permanganate, or with

corrosive sublimate, or where the wound, instead of being dusted, has

the corrosive sublimate applied in the form of a plug. In each case the

preliminary irrigation with the corrosive sublimate solution is dispensed

with. This, however, should on no account be omitted. In our opinion it

constitutes the very essence of the rationality of the treatment.

_(b) Curative_.--It may happen, however, and often does, that this first

injection of an antiseptic is unsuccessful in preventing organismal

infection of the wound. In this case grave constitutional disturbance and

other untoward symptoms such as we have already described quickly make

their appearance.

The animal should now be placed in slings and preparations made for

actively treating the wound with antiseptics. Whether we fail or not, we

have the satisfaction of knowing that we have given to the patient the best

and the only chance of recovery.

It should be remembered, however, and should be pointed out to the owner,

that with purulent arthritis fully developed, with the grave constitutional

changes it occasions, and with the ever-present danger of a general

septic invasion of the blood-stream, that the human surgeon under such

circumstances offers to his patient the alternatives of amputation or

probable death. With us no such alternative is possible. It is either

return the joint to some semblance of its former usefulness, or destroy the

patient.

In this case we advise the injection of the original wound, and also such

fistulous openings as may have formed, with the 1 in 1,000 sublimate

solution. Also, in order to avoid the sometimes abortive attempts of the

antiseptic pad, to maintain a condition of asepsis around the wound, we

advise the continual soaking of the whole foot in a cold antiseptic bath.

This may be either carbolic acid 1 in 20, or--what is less volatile,

perhaps more effectual, and certainly more economical--perchloride of

mercury 1 in 1,000.

It has been our good fortune, even when we have seen the foot almost

detached from the limb by the devastating inroads of the pus, to see

the suppurative process by this means gradually overcome, a reparative

anchylosis set in, and the animal restored to good health and usefulness,

if not to soundness.

Once the suppurative process is checked and anchylosis commences, it is

good treatment to smartly blister the whole of the region of the coronet,

the pastern, and the wound itself with a mixed blister of cantharides and

biniodide of mercury, repeated at intervals of a fortnight. This prevents

to some extent further infection of the wound, and assists also in

promoting the changes that tend to anchylosis.

_(d)_ ANCHYLOSIS.

The word anchylosis signifies the stiffening of a joint. When one has read

the serious changes occurring within the joint in the more serious forms

of arthritis, it is easy to understand how it comes about. In suppurative

arthritis, for instance, we have the synovial membrane destroyed, the

articular cartilages partly or wholly obliterated, and the former

boundaries of the joint entirely lost. If the animal lives, nature is

bound to make repair of a sort. The synovial membrane and the articular

cartilages utterly destroyed, as we have described, cannot again be

replaced. Nature can only build again from such materials as are left to

her. In this case the material is bone.

It must be remembered, however, that often the bone has been so diseased

that spots of necrosis or caries within it are bound to remain unless moved

by operative interference. Such diseased portions, when dealing with the

foot, are beyond reach of the surgeon's knife, and we have no alternative

but to allow them to remain. We get, therefore, in many cases, a condition

of rarefactive ostitis occurring side by side with a slowly progressive

caries within the bone, while outside is occurring an osteoplastic

periostitis. The concurrence of these conditions leads in time to great

increase in size of the parts, together with increasing anchylosis and

deformity.

C. NAVICULAR DISEASE.

_Definition_.--Chronic inflammatory changes occurring in connection with

the navicular bursa, affecting variously the bursa itself, the perforans

tendon, or the navicular bone, and characterized by changes in the form

of the hoof and persisting lameness. The disease is commonly noticed

in thoroughbreds or in horses of the lighter breeds, and is but seldom

observed in heavy cart animals. Usually it is met with in one or both

fore-feet. Although of extremely rare occurrence, it has been noticed in

the hind.

_History_.--To English veterinarians appears to belong the credit of

discovering navicular disease. As early as 1752 we find one, Jeremiah

Bridges, in 'No Foot, No Horse,' drawing attention to 'coffin-joint

lameness,' and advocating for its treatment setoning of the frog. It

appears, too, that Moorcroft, prior to his departure for India in 1808, was

acquainted with what was then known as coffin-joint[A] lameness, having

drawn attention to it in 1804 in a letter to Sir Edward Codrington.[B] In

1819 Moorcroft made it even plainer still that he was fully acquainted with

what we now know as navicular disease. This we learn from a letter written

by him to Sewell, in which he laid claim to being the originator of

neurectomy. In this letter he says:

[Footnote A: The coffin-joint at this time included the navicular bursa.]

[Footnote B: Percival's 'Hippopathology,' vol. iv., p. 132.]

'On dissecting feet affected with these lamenesses, the flexor tendon was

now and then observed to have been broken, partially or entirely, but

more commonly to have been bruised and inflamed in its course under the

navicular or shuttle bone, or at its insertion into the bone of the foot.

Sometimes, although seldom, the navicular bone itself has been found to

have been fractured; at others its surface has been deprived of its usual

coating, and studded with projecting points or ridges of new growth, or

exhibiting superficial excavations more or less extensive.'[A]

[Footnote A: _Ibid_.]

_Pathology and Point of Commencement of the Disease_.--The exact position

in which the diseased process starts has for a long time been a subject

of discussion, and even now it is doubtful whether the point has been

definitely settled. To mention but a few among many: We find Mr. Broad, of

Bath, strenuously insisting on the fact that the disease commences in the

interior of the navicular bone. Just as strenuously we find the editor of

the journal in which the matter is being discussed, the late Mr. Fleming,

asserting that the disease commences in the bursa.[A] Others, too, hold

that the disease commences primarily in the tendon. Wedded to this view was

the discoverer, Mr. Turner, of Croydon; while Percival commits himself to

the statement that it is either the central ridge or the postero-inferior

surface of the navicular bone, or the opposed concavity in the perforans

tendon, that shows the earliest signs of the disease. The observations made

by Dr. Brauell, the first Continental writer to fully describe the disease,

led him to the statement that neither the bone nor the bursa was the

_invariable_ starting-point of the trouble, but that usually it commenced

in inflammation of the bursa itself.

[Footnote A: Percival's 'Hippopathology,' vol. iv., p. 132.]

Without, therefore, committing ourselves to an expression of opinion as

to the precise starting-point of the affection, we shall describe the

pathological changes occurring in navicular disease as noted in (1) the

bursa, (2) the cartilage, (3) the tendon, and (4) the bone.

1. _Changes in the Bursa_.--Upon the internal surface of the bursal

membrane is first noticed a slight inflammatory hyperæmia, accompanied

by more or less swelling and tumefaction, owing to its infiltration with

inflammatory exudate. The portion covering the hyaline cartilage of the

navicular bone has lost its peculiar pearl-blue shimmer, and become a dirty

yellow.

Remembering that the bursal membrane is a synovia-secreting one, and

bearing in mind what happens in ordinary synovitis and arthritis (with

which, of course, this may be very closely compared), we shall first expect

changes in the bursal contents. It is highly probable, though difficult of

proof, that in the very early stages the chronic inflammatory stimulus has

the effect of increasing the flow of synovia. In every case, however, where

it can with any certainty be said that navicular disease exists, it is too

late to meet with this condition. The disease has then progressed until

destruction of the secreting layer of the bursal membrane has been

seriously interfered with, and in this case we find a distinct deficiency

in the quantity of synovia in the bursa. In advanced cases it is even found

that the bursa is _absolutely dry_.

2. _Changes in the Cartilage_.--Directly that portion of the bursal

membrane covering the cartilage is the subject of inflammatory change, the

cartilage itself, by reason of its low vitality, soon suffers.

Under a process, which we may term 'dry ulcerative,' the cartilage covering

the ridge on the lower surface of the bone commences to become eroded, and

in appearance has been likened, both by English and Continental writers, to

a piece of wood that has been worm-eaten (see Fig. 161).

[Illustration: FIG. 161.--NAVICULAR BONE (POSTERO-INFERIOR SURFACE) SHOWING

THE 'WORM-EATEN' APPEARANCE CAUSED BY EROSION OF THE HYALINE CARTILAGE, AND

COMMENCING RAREFACTIVE ARTHRITIS.]

'At this stage, or much earlier'--we are quoting Colonel Smith,

A.V.D.--'may be found calcareous deposits in the fibro-cartilage and the

bone. They are scattered like fine sand here and there, generally across

the inferior half of the face of the bone; they are sometimes numerous,

frequently scanty, occasionally entirely absent. The amount of calcareous

degeneration depends upon the lesions present. If much destruction of bone

exists, there will be but few calcareous deposits; whilst if there are many

calcareous deposits, there may be but slight ulceration of bone tissue, and

perhaps none at all. In fact, I have held the opinion, and see no reason to

modify it, that calcareous deposits are safeguards against caries.'[A]

[Footnote A: _Journal of Comparative Pathology and Therapeutics_, vol. vi.,

p. 195.]

3. _Changes in the Tendon_.--The effect of these calcareous deposits on

the under surface of the bone is to produce a certain amount of roughness.

Seeing that with every movement of the foot the perforans tendon is called

upon to glide over this surface, it is clear that a secondary effect must

be that of inducing erosion and destruction of the tendon. The point at

which this usually commences is at the bottom of the depression that

accommodates the ridge on the bone. With erosion of the cartilage and of

the tendon at points exactly opposite each other, we have two surfaces come

together that are prone to readily unite, and fibrous tissue adhesions

often take place between the bone and the tendon. In some measure this

accounts for the torn and ragged appearance of the tendon. Adhesions take

place, and, under some small strain, are broken down. This may happen more

than once or twice, and with each breaking of the adhesion between the bone

and tendon, fibres from the latter are lacerated and torn from their place

(see Fig. 162).

4. _Changes in the Bone_.--The changes occurring in the bone are

essentially those of a rarefactive ostitis. These changes are described by

many writers, and, whether originating primarily in the bone or not, it

seems certain that extensive changes may have occurred within the bone,

with but little or nothing to be noted on its outer surface. It would seem

that the first change is one of congestion of the vessels of the bone's

cancellous tissue. With the cause, whatever it may be, in constant

operation, the congestion persists until a low type of inflammation is set

up, interfering, not only with the flow of synovia in the adjoining bursa,

but with the nutrition of the bone itself. As the disease progresses, there

is softening and enlarging of the cancellated tissue towards the centre

of the bone. The cells break up, and absorption takes place. This goes on

until a large portion of the interior of the bone is in a state of dry

necrosis, with, in many cases, but slight signs of mischief on the exterior

of the bone.

In other cases, however, the changes in the interior of the bone are

accompanied by well-marked lesions on its gliding or postero-inferior

surface, and by evidences of an osteoplastic periostitis along its edges.

That an osteoplastic periostitis has been in existence is witnessed by the

appearance along the edges of the bone of numerous outgrowths of bone,

termed osteophytes (see Fig. 163).

[Illustration: FIG. 162.--A FOOT WITH THE SEAT OF NAVICULAR DISEASE

EXPOSED. On the anterior surface of the perforans fibres of the tendon are

seen to be torn away from their abnormal adhesion with the navicular bone,

while others are seen to be still attached thereto. The surface of the

navicular bone itself exhibits small defects in the bony substance, which

have been brought about by a rarefactive ostitis. _a_, The perforans tendon

cut through and reflected; _b_, the sole.]

The interosseous and postero-lateral ligaments of the articulation

often participate in the inflammatory changes, and in many cases become

completely ossified. The true articulatory surface of the bone, that

articulating with the os pedis and with the os coronæ, is never affected.

_Causes_.--In enumerating the causes of navicular disease, we shall

follow the example of Colonel Smith and classify them under certain

headings--namely, (1) _Hereditary Predisposition_; (2) _Compression_; (3)

_Concussion_; (4) _A Weak Navicular Bone_; (5) _A Defective or Irregular

Blood-supply to the Bone_; and (6) _Senile Decay_.

[Illustration: FIG. 163.--THE NAVICULAR BONE FROM A CASE OF LONG-STANDING

NAVICULAR DISEASE. The erosion of the cartilage on its central ridge is

most marked, and the porous appearance of the bone thus uncovered points

to the existence within it of a rarefactive ostitis. Along its edges

large osteophytic outgrowths speak of the effects of an osteoplastic

periostitis.]

1. _Hereditary Predisposition_.--That navicular disease is hereditary is

a fact that has for a long time been insisted on, and has come to be so

generally admitted that we do not intend to dwell on it here. As we have

said before, it is found in the lighter breeds of horses (and, according

to Zundel, especially in the English breeds), and is there seen to be

frequently transmitted from parent to offspring.

2. _Compression_.--By this is meant the compression of the navicular bone

between the os pedis and the os coronæ in front, and the perforans tendon

behind.

In order to appreciate this explanation of the causation of navicular

disease at its true value, it will be well to consider briefly the

physiology of the parts in question.

The navicular bone is what we may term a complement of the os pedis. It

exists, in fact, simply in order that the os coronæ may have a sufficiently

large articulatory surface to play upon. One wonders at first that Nature

did not arrive at this by originally placing a larger bone below. Colonel

Smith explains this by suggesting that this would in all probability have

meant its fracture. In progression the hind part of the foot comes to the

ground first, and upon the hinder portion of the articulation would fall

the first effects of concussion, together with the greater part of the

body-weight. A yielding joint was in this position necessary, and that

formed by the navicular bone fills all requirements.

In this connection one next considers the part played by the front limbs

during progression. As Zundel expresses it, they are columns of support

rather than of impulsion, and, as the body-weight is thrown forward by the

hind-limbs, it is the duty of the fore-limbs to receive it. The shock or

concussion of the body-weight thus thrown forwards is first received by

the muscles uniting the limb to the trunk, and a great part of it there

minimized by their sling-like attachment. It is further absorbed by the

shoulder-joint, and from there passed on to the almost vertical bony column

represented by the radius and ulna, the knee, and the metacarpus. On

reaching the first phalanx, a portion of the remaining force is passed on

to the front of the phalanges and loses itself in front of the hoof, while

the other portion is transmitted to the flexor tendons, finally to the

perforans, and to the posterior parts of the foot. During progression,

therefore, the navicular bone is constantly pushed downwards and backwards

by the bony column, and is just as constantly pushed forwards and upwards

by the resistance of the perforans tendon. This means, of course, that

the navicular bone is more or less constantly subject to compression,

and constant pressure, as we know full well, is a pretty sure factor

in bringing about malnutrition of the parts, with atrophy or chronic

inflammatory changes as an end result.

Even with the limb at rest the pressure on both sides of the navicular bone

is still constant. The only circumstances under which we can conceive of

it being entirely absent, in fact, are when the tension on the tendon is

relaxed, and the body-weight altogether removed by the animal adopting the

recumbent position.

The compression theory as to the causation of navicular disease was, we

believe, first originated by Colonel Smith. He, at any rate, has laid much

stress on it in his writings. If we accept it, and we see every reason

that we should, then we must, with the author, admit the possibility of

navicular disease arising from long standing in one position.

3. _Concussion_.--This we are bound to admit as a cause, and in so doing

partly explain the comparative, almost total, immunity of the hind-feet

from the disease. The fore-limbs, as we have already pointed out, are

little more than props of support, and the force of the propelled

body-weight is transmitted largely down their almost vertical lines, to

end largely in concussion in the foot. With the hind-limbs matters are

different. 'These,' as Percival explains it, 'have their bones obliquely

placed, so as to constitute, one with the other, so many obtuse angles, to

the end, that by forming powerful levers, and affording every advantage for

action to the muscles attached to them, they may be fitted for the purpose

of propulsion of the body onward.'

The effect of these several obtuse-angled joints in the limb is to absorb

the greater part of the force exerted by the body-weight before it reaches

the foot. When with this we take the facts that the fore-limbs have to

carry the head and neck, and that they have to bear this added weight, plus

a propelling force from behind, we see why it is that they should be so

subject to the disease, and the hind-limbs so exempt.

As pointing out the part that concussion plays in its causation, we may

mention that navicular disease is a disease of the middle-aged and the

worked animal. It is interesting to note, too, that it occurs in animals

with well developed frogs--in feet in which frog-pressure with the ground

is most marked. This at first sight appears to flatly contradict what we

have said with regard to frog-pressure in other portions of this work. With

this, however, must be reckoned other predisposing causes. In this case it

is not to frog-pressure alone we must look, but to the condition of the

frog itself, and that of the neighbouring parts. It is when we have a frog

which, though well developed and apparently satisfying all demands as

to size and build, is at the same time composed of a hard, dry, and

non-yielding horn that we must look for trouble.

The foot predisposed to navicular disease is the strong, round, short-toed

or clubby foot, open at the heels, with a sound frog jutting prominently

out between them. Here is a frog exposed to all the pressure that might

be desired for it, bounded at its sides by heels thick and strong, and

indisposed to yield, and itself liable, from its very exposure, to become,

in the warm stable, hard and dry, and incompressible' (Percival).

Here, instead of acting, as normally it should, as a resilient body, and an

aid to the absorption of concussion, it seems rather to play the part of

a foreign body, and to bring concussion about. Seeing, then, that the

navicular bursa is in very near contact with it, it is conceivable that

this joint-like apparatus should suffer, and the pedal articulation be left

unaffected, the more so when we take into consideration the compression

theory just described.

4. _A Weak Navicular Bone_.--When the disease commences first in the

bone--and there is no denying the fact that sometimes, although not

invariably, it does--it may be explained by attributing to the structure of

the bone an abnormal weakness in build.

The navicular bone consists normally of compact and cancellated tissue

arranged in certain proportions, the compact tissue without, and the

cancellated within. These proportions can only be judged of by the

examinations of sections of the bone, and when it is found in any case that

the cancellated tissue bulks more largely in the formation of the bone than

normally it should, we have what we may term a weak navicular bone. In this

connection Colonel Smith says: 'Though it is far from present in every case

of the disease, still I consider it a factor of great importance.'

5. _A Defective or Irregular Blood-supply to the Bone_.--This, Colonel

Smith considers, is brought about by excessive and irregular work, and by

the opposite condition--rest. The author points out that the bloodvessels

passing to and from the navicular bone run in the substance of the

interosseous ligaments, or in such proximity to them that it is conceivable

that under certain circumstances mechanical interference may occur to the

navicular circulation. He further points out a fact that is, of course,

well known to every veterinarian, that in periods of work the circulation

of the foot is hurried, and that in rest there is always a tendency to

congestion; and he says in conclusion: 'I cannot help thinking that

irregularities in the blood-supply in a naturally weak bone must be a

factor of some importance, especially when the kind of work the horse is

performing is a series of vigorous efforts followed by rest.'

6. _Senile Decay_.--With approaching age the various tissues lose their

vigour, and are prone to disease. The navicular bone and surrounding

structures are not exempt. With the other and more active causes we have

described acting at the same time it is not surprising that navicular

disease is seen as a result.

In conclusion, it is well, perhaps, to say that, no matter to which

particular theory of causation we may lean, we should make up our minds to

consider them as a whole. While one cause may be exciting, the other may

be predisposing, and the two must act together before evil results are

noticed. It may be that even more than two are concerned in bringing on the

disease, and to each the careful veterinarian will give due consideration.

_Symptoms and Diagnosis_.--In the early stages of navicular disease the

symptoms are obscure. Pointing of the affected limb is the first evidence

the animal gives. This, however, more often than not, goes unnoticed,

and the first symptom usually observed by the owner or attendant is the

lameness. Even this is such as to at first occasion no alarm, being

intermittent and slight, and only very gradually becoming marked. In a few

cases, however, lameness will come on suddenly, and is excessive from the

commencement. It is the lameness, slow in its onset, intermittent in

its character, and gradual in its progress, however, that is ordinarily

characteristic of navicular disease.

The animal is taken out from the stable sound, with just a vague suspicion,

perhaps, that he moved a bit stiffly. While out he is thought by his driver

or rider to be going feelingly with one foot or with both. Even this is not

marked, and the driver has some difficulty in assuring himself whether or

no he really observed it, or whether it was but imagination.

On the return home the limb is examined, and nothing abnormal is to be

found. The leg is of its normal appearance, and neither heat nor tenderness

is to be observed in it or in the foot. On the following day the animal

again is sound, and the lameness of the previous day is put down to a

slight strain or something equally simple. The patient is then, perhaps,

rested for a day or two. When next he is worked he again moves out from the

stable sound, but again during the going gives the driver the unpleasant

impression that something is amiss; and so the case goes on. One day the

owner fears the animal is becoming seriously enough affected to warrant him

in calling in his veterinary surgeon; the next he is confidently assuring

himself that nothing is wrong.

Perhaps the animal is now rested for a week or two, or even for a month or

two, hoping that this will put him sound. Immediately on commencing work,

however, the same symptoms as before assert themselves, and the veterinary

surgeon is called in.

With a history such as we have given the veterinarian's suspicions are

aroused. He has the animal trotted, and may notice at this stage that there

is an inclination to go on the toes, that the lame limb or limbs are not

put forward freely, and that progression is stilty and uncertain; it

is such, in fact, as to at once suggest the possibility of corns being

present.

In some cases there is just the suspicion of a limp with one limb, and

this only at intervals during the trot. At one moment the veterinarian

is positive that he sees the animal going lame; at another he is just as

confident he sees him coming towards him sound.

Nothing is found in the limb--neither heat, tenderness, nor swelling. There

is nothing in the gait (either a limited movement of the radius, or a

circular sweep with the leg) to indicate shoulder or other lameness, and

the veterinary surgeon, by eliminative evidence, is bound to conclude that

the trouble is in the foot.

The foot is then examined--pared, percussed, pinched, and in other ways

manipulated--but nothing further is forthcoming. In such a case the

veterinary surgeon is wise to declare the abortive result of his

examination, to hint darkly of his suspicions, and to suggest a second

examination at some future date. It may be that two, three, four, or even

more, such examinations are necessary before he can justly pronounce a

positive verdict.

Later he is enabled to do this by an increase in the severity of the

symptoms, and by the changes that take place in the form of the foot.

The lameness is now more marked, and the 'pointing' in the stable more

frequent. With regard to the latter symptom, it has been seriously

discussed whether the horse with navicular disease points with the heel

elevated or with it pressed to the ground. In either case, of course, the

limb is advanced; but while some hold that the phalangeal articulations are

flexed and the heel slightly raised, in order to relieve the pressure of

the perforans tendon on the affected area, and so obtain ease, there are

others who hold that the heel is pressed firmly to the ground in order to

deaden the pain. It may be, and most probably is, that both are right; but,

in our opinion, there is no doubt whatever that pointing with the heel

elevated is by far the most common.

The lameness is now excessive, and is especially noticeable when the animal

is put to work on a rough or on a hard ground. Even now, however, heat of

the foot or tenderness is so slight as to be out of all proportion to the

alteration in gait.

With the case thus far advanced, evidence of pain may be obtained by

pressing with the thumb in the hollow of the heel. Evidence of pain may

also be obtained by using the farrier's pincers on the frog. These methods,

however, are never wholly satisfactory, as a horse with the soundest of

feet will sometimes flinch under these manipulations.

Extreme and forcible flexion of the corono-pedal articulation also

sometimes gives evidence of tenderness. In this case the foot is held up,

the animal's metacarpus resting on the operator's knee, and the toe of the

hoof pushed downwards with some degree of force.

The same movement of the joint is given by causing the animal to put full

weight upon the diseased limb, a small wedge of wood being first placed

under the toe. In this manner the pressure of the perforans tendon upon the

bursa is greatly increased, and the animal is caused to show symptoms of

distress.

The lameness may also be increased, and diagnosis helped, by paring

the heels, so as to leave the frog prominent and take the whole of the

body-weight. The same end is also obtained by applying a bar shoe. This was

originally pointed out by Brauell, and is quoted by Zundel and by Möller.

The changes in the form of the hoof may now be noticed. These are largely

dependent on the fact that more or less constantly the patient saves the

heel. The horn of the walls in this region, and the horn of the frog,

is thereby put out of action and induced to atrophy. The hoof gradually

assumes a more upright shape, and the heels contract. We thus get a hoof

which is visibly narrowed from side to side, with a frog that is atrophied

and often thrushy, and with a sole that is abnormally concave, hard, and

affected with corns.

When occurring in the hind-feet--a condition that is rare, but which has

been noticed by Loiset, and quoted by Zundel--the animal is stiff behind,

walks on his toes, and gives one the impression that he is suffering from

some affection in the region of the loins.

One such case is reported by an English veterinary surgeon, and we quote it

here:

'A gray gelding, and a capital hunter, the property of a gentleman in this

neighbourhood, became lame in the near fore-foot after the hunting season

of 1859. The lameness was believed to be due to navicular disease.

The operation of neurectomy was ultimately had recourse to. The horse

subsequently did his work as well as ever, and was ridden to hounds

regularly till the end of the year 1861, when he went lame of the off

fore-foot. From this date he also showed very peculiar action behind, and

was at times lame of both hind-limbs without any apparent cause.

'In the year 1862, from the groom's indiscreet use of physic,

superpurgation was brought on which caused the animal's death. On a

post-mortem examination being made, the horse was found to have _navicular

disease of all four feet_. It is worthy of note that this horse had

always "extravagant" action behind, but was a remarkably quick and good

jumper.'[A]

[Footnote A: F. Blakeway, M.R.C.V.S., _Veterinarian_, vol. ii., p. 21.]

_Differential Diagnosis_.--Navicular disease may be mistaken for ordinary

contracted foot. It will be remembered, however, that in the early stages

of navicular disease contraction is absent, and that it is only when the

disease in the bursa is of long standing that contraction comes on. With

ordinary contracted foot, too, careful paring and suitable shoeing soon

sees a diminution in the degree of lameness, and a return to the normal in

shape (see Treatment of Contracted Foot, p. 125). With navicular disease,

however, such shoeing as is beneficial in the treatment of contracted foot

(notably the various methods of giving to the frog counter-pressure with

ground) soon brings on an aggravation of the lameness.

It is, perhaps, even more likely to be confounded with contraction when we

have with the contraction a state of atrophy and thrush of the frog. With

a frog in this condition pressure will give rise to pain, and navicular

disease be erroneously judged to be present. In such a case we must rely

wholly upon either extreme flexion or extreme extension of the joint to

guide us, when, if contraction _only_ is the offending condition, no

symptom of pain will be shown.

Navicular disease may also be confused with rheumatic affections,

with sprain of the posterior ligaments of the first interphalangeal

articulation, and with sesamoid lameness. Mistakes are sometimes made, too,

especially with a hasty observer, in confounding it with shoulder lameness.

In rheumatism the constant changing of the seat of pain, the sometimes

elevated temperature, and the appearance of symptoms of heat, tenderness,

and swelling in the affected area should guide one to a right conclusion.

In sprain of the posterior ligaments of the coronet and in sesamoid

lameness, nothing but a careful examination and manipulation of the parts

will ward off error, for in each of these cases there is 'pointing' and

resting of the limb, and considerable disinclination to put weight firmly

upon it. If at the same time manipulation gives distinct evidence of pain,

all doubt may be set at rest.

Roughly speaking, sesamoid lameness is a condition of the gliding surface

of the sesamoids, and the face of the tendon playing over them, similar to

that found in navicular disease. All symptoms of pointing, the constant

maintaining of the limb in a state of flexion, and a feeling manner of

progression are again all present. It is plain from this that in all cases

where an animal with a gait at all suggestive of navicular disease is

brought for our examination, the manipulation of the limb should be

thorough. The character of the lameness is almost sure to deceive us; and

it is not until we are able to obtain local symptoms pointing to the one or

the other of the conditions we have enumerated that a decisive opinion may

be given. In sesamoid lameness the local symptoms are those of heat and

pain in the fetlock on palpation, and a swelling of the affected parts,

such swelling being at first slight, yielding, and barely distinguishable,

and afterwards larger, bony and hard, and more marked. Later still there is

distinct evidence of 'knuckling' over at the fetlock and inability to fully

flex it.

In cases of shoulder lameness the gait alone should be sufficient to render

liability of error small, for with nearly every case there is a manifest

inability to 'get the limb forward', and this is best seen at a side view

when the animal is trotting past the observer. When trotting towards

one, there is a further and unmistakable symptom common to most shoulder

lamenesses that serves to distinguish it at once, and that is the peculiar

'sweeping' outwards with the affected limb.

Lastly, with either of the conditions we have just mentioned, it is the

exception to get contracted foot follow on. With navicular disease it

sooner or later makes its appearance.

_Prognosis_.--The prognosis of navicular disease (once diagnosed with

certainty) must almost of necessity be unfavourable. The facts that the

disease has made serious progress before it is really noticeable, that

the situation of the parts prohibits operative interference, and that the

disease is one of a chronic and slowly progressive type, all point to an

unfavourable termination.

_Treatment_.--We have seen from the pathology of this disease that it may

commence either as a rarefactive ostitis, or as a synovitis and tenositis

in connection with the bursa. With the former condition in existence, or

when this and the synovitis has led to erosion of the cartilage, treatment

is probably of no avail, on account of the more chronic nature of these two

conditions. When, however, the condition is simply that of synovitis or

tenositis, a more or less acute condition, we may assume that suitable

treatment and a long rest will bring about resolution.

The first indications in treatment are those of what we may term 'nursing'

the foot. It should have sufficient rest, should be placed so as to

minimize as far as possible compression of the parts, and should have

its posterior half treated so as to render it softer and less liable to

concussion.

The period of rest required cannot be satisfactorily advised, and the

practitioner is wise who makes it a long one. Best should be advised, in

fact, long after symptoms of lameness have disappeared and recovery is

judged to have taken place.

Compression of the parts may be somewhat minimized, if the animal be kept

in the stable, by allowing the floor upon which the front-feet are to stand

to be slightly sloping from behind forwards. The same effect, though not so

marked, is obtained by removing the shoes, and considerably lowering the

wall at the toe, while allowing that of the heels to remain. It may here be

remarked that it is a good practice to allow the shoes to remain on, and

this even when the animal is at grass. They should, however, be frequently

removed, and the foot trimmed as we have directed.

With the foot thus trimmed so as to most suitably adjust the angles of

the articulations, it should next be thoroughly pared and rasped in its

posterior half, so as to render the horn of the sole and the frog and the

horn of the quarters as thin as possible. The heels, however, should not be

excessively lowered, _if at all_. We now have the foot in a soft condition,

and easily expanded. It should, if possible, be kept so; and this may be

done either by the use of poultices, by tepid baths, or by standing the

animal upon a bedding that may easily be kept constantly damp. Such

materials as tan, peat moss, or sawdust, are either of them suitable.

All this, of course, calls for keeping the animal in the stable. It is far

better, however, more especially if a piece of marshy land is at hand, to

turn him out in that. A moderate amount of exercise is beneficial rather

than not, and the feet are thus constantly kept damp without trouble to the

attendants.

The second indication in the treatment is that of applying a

counter-irritant as near to the diseased parts as possible. Regarding its

efficacy we must confess to being somewhat sceptical. The treatment has

been constantly practised and advised, however, and we feel bound to give

it mention here. A smart blister may, therefore, be applied to the whole of

the coronet, and need not be prevented from running into the hollow of the

heel.

Instead of blistering the coronet (or in conjunction with that treatment),

the counter-irritant may be applied by passing a seton through the plantar

cushion or fibro-fatty frog. Setoning the frog appears to have been

introduced by Sewell. In many cases great benefit is claimed to have been

derived from it, especially by English veterinarians of Sewell's time, and

by others on the Continent. Percival, however, was not an advocate for it,

and, at the present day, it is a practice which appears to have dropped out

of use altogether.

[Illustration: FIG. 164.--FROG SETON NEEDLE.]

To perform this operation a seton needle of a curved pattern is needed

(see Fig. 164). This is threaded with a piece of stout tape dressed with a

cantharides, hellebore, or other blistering ointment, and then passed in at

the hollow of the heel, emerging at the point of the frog. The course the

needle should take will be understood from a reference to Fig. 165.

The seton may be passed with the horse in the standing position. Previously

the point of the frog should be thinned, and the animal should be twitched.

After-treatment consists simply in moving the seton daily, and dressing it

occasionally with any stimulating ointment, or with turpentine.

If, in spite of these treatments, the disease persists, then nothing

remains but neurectomy.

D. DISLOCATIONS.

The firm and rigid manner in which the bones of the pedal articulation

are held together renders dislocation of this joint an exceedingly rare

occurrence, and then it is only liable to happen under the operation of

great force. In the literature to our hand we have only been successful

in discovering one reported instance, and, strange to say, in this, a

well-marked case, the cause was altogether obscure. We quote the case at

the end of this section.

[Illustration: FIG. 165.--DIAGRAM SHOWING THE COURSE TAKEN BY THE NEEDLE

WHEN SETONING THE FROG. This is shown by the dotted curved line _a, b_.

1, The navicular bone; 2, the plantar cushion; 3, the os pedis; 4, the

perforans tendon.]

A partial dislocation of this articulation is the condition met with in

'Buttress Foot.' In this case the fracture of the pyramidal process, and

the consequent lengthening of the tendon of the extensor pedis, allows the

os coronæ to occupy upon the articulatory surface of the os pedis a more

backward position than normally it should.

It is quite probable, too, that slight lesions of the other restraining

ligaments and tendons of the articulation may bring about a similar though

less marked condition. We may be quite sure of this--that whenever such

lesions (as, for example, sprain and partial rupture of the lateral

ligaments) do occur, and the normal position of the opposing bones is

changed, if only slightly, that great pain and excessive lameness must be

the result, and this with but little to show in the foot. Many of our cases

of obscure foot lameness might, if capable of demonstration, turn out to be

cases of sprain and partial dislocation of the pedal articulation.

_Recorded Case_.--'The animal, a trooper of the 8th Hussars, was found on

the morning of April 17 unable to bear any weight on the limb (the

near hind). Cause not known--the heel-rope I thought at first; but on

investigation I found the heel-rope had been on the other leg.

_Diagnosis_.--Dislocation of the left os coronæ from the articulating

surface of the os pedis in a backward direction.

'Every devisable means were unsuccessful in reducing the limb to its

natural position. The horse was thrown, and a strong rope, with four men

pulling at it, was fastened round the hoof, whilst I put my knee to the

back of the pastern, using all possible force, with one hand to the foot

and the other to the fetlock, but all to no purpose. Next day other means

were tried. First by throwing the horse and placing him on his belly, with

the fore-legs stretched out forwards, and the hind-legs backwards. This I

did so as to get the injured limb placed as nearly flat on the ground as

possible, with its anterior aspect downwards. Then a very heavy man, with

his boots off, was made to jump on the back of the pastern, where the

prominence showed most; and afterwards, when these means failed, a strong

piece of wood, well covered with leather, was placed (where the hollow of

the heel ought to have been) on the most prominent part, and hit several

times with a heavy hammer; but all efforts were futile.

'_Prognosis_.--Unfavourable. During the latter operations I had a very

strong pressure applied to the hoof, and the horse firmly fastened in every

way, and it appeared as though no amount of force would ever reduce the

dislocation.

'_Tautological_.--The case was destroyed on April 30, being of no further

use to the service.

'_Post-mortem_.--The os coronæ was found to have slipped out of the

articulating cavity of the os pedis, backwards and past the lateral

ligaments. These last-named structures prevented the bone being forced

forward into its proper position, being firmly locked over the lateral

prominences. The capsular ligament was considerably lacerated and inflamed,

causing slight effusion and swelling about the region of the coronet.'[A]

[Footnote A: T. Flintoff, A.V.D., _Veterinary Journal_, vol. xix., p. 74.]

_Treatment_.--After the forcible means of reduction related by Mr.

Flintoff, we may add that when they are successful, they should be followed

by suitable bandaging of the parts, and rest. The first is effected by

applying plaster of Paris and linen, and the second by having the animal

put in slings.

INDEX

Accidental tearing off of the entire hoof

Acute arthritis

causes of

symptoms of

treatment of

Acute laminitis

causes of

complications in

congestion in

course of

definition of

diagnosis in

exudation in

pathological anatomy of

prognosis in

suppuration in

symptoms of

treatment of

Acute periostitis simple

Acute simple coronitis

causes of

definition of

symptoms of

prognosis of

treatment of

Acute simple synovitis

Advantages of neurectomy

Amputational neuroma after neurectomy

Anatomy, pathological, of corn

Applying poultices, method of

Arteries of the foot

Arthritis, acute

causes of

symptoms of

treatment of

Arthritis, simple or serous

Arthritis, suppurative

causes of

definition of

diagnosis of

pathology of

symptoms of

treatment of

Articulation, the first interphalangeal

Articulation, the second interphalangeal

Bar pad and a half-shoe in the treatment of contracted feet

Bar shoes in the treatment of contraction

Bayer's treatment for chronic laminitis

Bermbach's treatment for canker

Bind

Bone, caries of

Bones, fracture of the, after neurectomy

Bones, fracture of the

Bones, necrosis of

Bones, the

Brittle hoof

causes of

definition of

symptoms of

treatment of

Broad's treatment of laminitis

Broué's expansion shoe

Bruised sole, chronic

Buttress foot

Canker

Bermbach's treatment of

causes of

definition of

differential diagnosis in

history of

Hoffmann's treatment of

Imminger's treatment of

Malcolm's treatment of

pathological anatomy of

prognosis in

Rose's treatment of

symptoms of

treatment of

Caries of bone

Caries of the os pedis in pricked foot

Cartilage, the lateral

Cartilaginous quittor

Causes of acute laminitis

of acute simple coronitis

of brittle hoof

of canker

of chronic coronitis

of chronic laminitis

of club-foot

of corn

of contracted feet

of coronary contraction of the

foot

of crooked foot

of curved hoof

of false quarter

of flat-foot

of keraphyllocele

of nail-bound

of navicular disease

of pumiced foot

of punctured foot

of ringed hoof

of sand-crack

of seedy-toe

of side-bone

of simple chronic coronitis

of simple cutaneous quittor

of specific coronitis

of sub-horny quittor

of thrush

of weak heels

Caustic solution, Villate's

Changes in the bone in navicular disease

in the bursa in navicular disease

in the cartilage in navicular disease

in the internal structures of the foot in contraction

in the tendon in navicular disease

Charlier shoe, the

Charlier shoeing for contracted foot

Chemical properties of horn

Chronic coronitis, simple

causes of

definition of

symptoms of

treatment of

Chronic bruised sole

treatment of

Chronic laminitis

Bayer's treatment of

causes of

definition of

Gross's treatment of

Gunther's treatment of

Imminger's treatment of

Joly's treatment of

Meyer's treatment of

pathological anatomy of

surgical shoeing for

symptoms of

treatment of

treatment of, by ligaturing the digital arteries

Chronic oedema of the leg after neurectomy

Chronic synovitis

Clamp, sand-crack, Koster's

McGill's

Vachette's

Clamping sand-cracks, methods of

Classification of corns

of punctured foot according to the situation of the wound

of sand-crack

of quittor

Club-foot

causes of

definition of

symptoms of

treatment of

Cocaine injections as an aid to diagnosis in foot lamenesses

Colic, metastatic, in laminitis

Commencement, point of, in navicular disease

Common situations of the wound in punctured foot.

Complicated sand-crack, operations for

Complications in coronitis

in laminitis

in pricked foot

in sand-crack

in simple or cutaneous quittor

in sub-horny quittor

Compression as a cause of navicular disease

Concussion as a cause of navicular disease

Conformation, faulty

Congestion in laminitis

Contracted foot

causes of

changes in the internal structures of

definition of

local or coronary

prognosis of

surgical shoeing for

symptoms of

treatment of

Contraction of the foot, a bar pad and a half-shoe in the treatment of

bar shoes in the treatment of

expansion shoes in the treatment of

Corn

causes of

classification of

definition of

pathological anatomy of

prognosis in

surgical shoeing in

symptoms of

the dry

the moist

the suppurating

treatment of

Coronary contraction of the foot

causes of

definition of

symptoms of

treatment of

Coronary cushion, the

Coronary edge of the wall, expansion and contraction of the

Coronitis

acute simple

causes of

complications in

definition of

prognosis of

symptoms of

treatment of

Coronitis, simple chronic

causes of

definition of

symptoms of

treatment of

Coronitis, specific

causes of

definition of

symptoms of

treatment of

Course of acute laminitis

Crooked foot

causes of

definition of

symptoms of

treatment of

Curved hoof

causes of

definition of

treatment of

Cushion

the coronary

the plantar

Cutaneous or simple quittor

De Fay's expansion shoe.

Defective or irregular blood-supply to the bone a cause of navicular

disease

Definition

of acute laminitis

of acute simple coronitis

of brittle hoof

of canker

of chronic coronitis

of chronic laminitis

of club-foot

of contracted foot

of corn

of coronary contraction of the foot

of crooked foot

of curved hoof

of false quarter

of flat-foot

of keraphyllocele

of nail-bound

of navicular disease

of pumiced foot

of punctured foot

of pyramidal disease

of quittor

of ringed hoof

of sand-crack

of seedy-toe

of side-bone

of simple chronic coronitis

of specific coronitis

of spongy hoof

of sub-horny quittor

of thrush

of weak heels

Development of the hoof

Diagnosis

of acute laminitis

of canker

of foot lameness by injections of cocaine

of navicular disease

of punctured foot

of pyramidal disease

of side-bone

of sub-horny quittor

Differential diagnosis in canker

in navicular disease

Diseases arising from faulty conformation

Dislocation of the os coronæ

recorded case of

Dislocations

Dry corn

Einsiedel's expansion shoe

Examining the foot method of

Exercise, forced, in the treatment of laminitis

Expansion and contraction

of the coronary edge of the wall

of the hoof under the body-weight

of the solar edge of the wall

of the sole

Expansion shoe Broué's

De Fay's

Einsiedel's

Hartmann's

Smith's

Expansion shoes in the treatment of contraction

Extensor pedis tendon, the

Extirpation

of the lateral cartilage in quittor

of the lateral cartilage, after Moller and Frick

of the lateral cartilage, after Bayer

Exudation in laminitis

False quarter

causes of

definition of

symptoms of

treatment of

Faulty conformation

diseases arising from

Feeding a cause of laminitis

Flat-foot

causes of

definition of

symptoms of

treatment of

Flexor pedis perforans tendon, the

Flexor pedis perforatus tendon, the

Foot, buttress

Foot, changes in the internal structures in contraction of the

Foot, contracted

causes of

definition of

prognosis of

symptoms of

treatment of

Forced exercise in laminitis

Fractures

Fractures of the bones after neurectomy

of the navicular bone

of the os coronæ

of the os pedis

Frog, the

Functions of the lateral cartilages

Gangrene of the sensitive structures in laminitis

Gathered nail

Gelatinous degeneration after neurectomy

Grooving the wall

in laminitis (Smith's operation)

in treatment of sand-crack

in treatment of side-bone (Smith's operation)

Gross's treatment of chronic laminitis

Growth of hoof, rate of

Gunther's treatment of chronic laminitis

Hartmann's expansion shoe

Heels, weak

causes of

definition of

symptoms of

treatment of

Heredity

as a cause of navicular disease

as a cause of side-bone

Histology of horn

History

of canker

of navicular disease

of neurectomy

Hind-feet, navicular disease in the

Hind-limb with the side-line, method of securing

Hoffmann's treatment of canker

Hoof, the

accidental tearing off of

expansion and contraction of

development of

rate of growth of

Horn

chemical properties of

histology of

Hutlederkitt

Imminger's treatment

for chronic laminitis

for canker

Immobilizing a sand-crack by grooving the wall, methods of

Infection of the limb, septic

Injections of cocaine as an aid to diagnosis in foot lameness

Interphalangeal articulation

the first

the second

Instruments

required in plantar neurectomy

in operations on the foot

Irregular blood-supply to the bone as a cause of navicular disease

Joly's treatment of chronic laminitis

Koster's sand-crack clamp

Keraphyllocele

causes of

definition of

pathological anatomy of

symptoms of

treatment of

Keratoma

Lameness, cocaine injections as an aid to diagnosis in

Laminæ, the sensitive

Laminitis

acute

Broad's treatment of

causes of

complications in

congestion in

course of

definition of

diagnosis in

exudation in

feeding, a cause of

forced exercise in the treatment of

gangrene of the sensitive structures in

grooving the wall in the treatment of

local applications in the treatment of

local bleeding in the treatment of

metastatic colic in

metastatic pneumonia in

neurectomy in

opening the sole in the treatment of

parturient

pathological anatomy of

periostitis and ostitis in

phlebotomy in the treatment of

prognosis in

rocker bar shoes in the treatment of

Smith's operation in

suppuration in

symptoms of

symptoms of, in the four feet

symptoms of, in the fore-feet alone

symptoms of, in the hind-feet alone

treatment of

Laminitis

chronic

Bayer's treatment of

causes of

definition of

Gross's treatment of

Gunther's treatment of

Imminger's treatment of

Joly's treatment of

Meyer's treatment of

pathological anatomy of

surgical shoeing for

symptoms of

treatment of

Laminitis, parturient

Lateral cartilage, the

extirpation of, in quittor, after Holier and Frick

extirpation of, in quittor, after Bayer

functions of

necrosed, pathological anatomy of

necrosis of

ossification of

wounds of

Leg, chronic oedema of the, after neurectomy

Length of rest required after neurectomy

Ligaments, the

Ligaturing the digital arteries, in chronic laminitis

Limb, septic infection of

Local applications in laminitis

Local bleeding in laminitis

Local or coronary contraction of the foot

Low ringbone

Malcolm's treatment of canker

McGill's sand-crack clamp

Median neurectomy

Metal plates in the treatment of sand-crack

Metastatic colic in laminitis

Metastatic pneumonia in laminitis

Methods of applying poultices

of examining the foot

of immobilizing sand-crack by grooving the wall

Methods of restraint

of securing a hind-limb with the side-line

of securing the foot to the cannon of another limb

Meyer's treatment of chronic laminitis

Moist corn

Nail-bound

causes of

definition of

symptoms of

treatment of

Nail-tread

Navicular bone, the

fracture of

Navicular bursa, puncture of the, in pricked foot

Navicular bursa punctured, treatment of

Navicular disease

causes of

changes in the bone in

changes in the bursa in

changes in the cartilage in

changes in the tendon in

definition of

diagnosis of

differential diagnosis of

history of

in the hind-feet

point of commencement of

prognosis of

symptoms of

treatment of

Necrosed lateral cartilage

pathological anatomy of

Necrosis of bone

of tendon and ligament in sub-horny quittor

of the lateral cartilage (cartilaginous quittor)

Necrotic plantar aponeurosis, treatment of

Nerve, reunion of, after neurectomy

Nerves, the

Neurectomy

advantages of

amputational neuroma in

fracture of the bones after

gelatinous degeneration after

history of

instruments required in

in laminitis

length of rest required after

persistent pruritus after

pricked foot after

reunion of divided nerve after

sequelæ of

stumbling after

use of the horse after

Neurectomy

median

plantar

Neuroma, amputational, after neurectomy

Oedema of the leg after neurectomy

Opening the sole in the treatment of laminitis

Operation for complicated sand-crack

for laminitis

for necrosed lateral cartilage in quittor

for necrosed plantar aponeurosis

for side-bone

Operations on the foot, instruments required in

Operations on the horn, treatment of contracted foot by

Os coronæ, the

dislocation of

fracture of

Os pedis, the

caries of, in pricked foot

fracture of

Osteoplastic ostitis

Osteoplastic periostitis

Ostitis in laminitis

Ostitis,

rarefying

osteoplastic

Ossification of the lateral cartilages (side-bone)

Overreach

shoeing for

treatment of

Parturient laminitis

Pathological anatomy of acute laminitis

of canker

of chronic laminitis

of corn

of keraphyllocele

of necrosed lateral cartilage

of pyramidal disease

of simple cutaneous quittor

of navicular disease

Pedal articulation, puncture of the

Perforans tendon, the flexor pedis

Perforates tendon, the flexor pedis

Periople, the

Periostitis and ostitis in laminitis

Periostitis, osteoplastic

Periostitis, recorded cases of

Periostitis,

simple acute

suppurative

Periostitis, treatment of

Persistent pruritus after neurectomy

Phlebotomy in laminitis

Plantar aponeurosis,

wounds of the

treatment of necrosed

Plantar cushion

Plantar neurectomy

history of

instruments required in

operation of

Pneumonia in laminitis

metastatic

Point of commencement of navicular disease

Poultices, methods of applying

Preventive treatment of cutaneous quittor

Pricked foot

after neurectomy

complications of

Prognosis

in acute simple coronitis

in canker

in contracted foot

in corn

in laminitis

in navicular disease

in punctured foot

in sand-crack

in simple cutaneous quittor

Properties of horn, chemical

Protection of sand-crack by metal plates

Pruritus after neurectomy

Pumiced foot

causes of

definition of

symptoms of

treatment of

Punctured foot

causes of

classification of

common situation of the wound in

complications in

definition of

diagnosis of

prognosis of

symptoms of

treatment of

Puncture of the navicular bursa

treatment of

Puncture of the pedal articulation

Purulent synovitis

Pyramidal disease

Quittor

classification of

definition of

Quittor, simple or cutaneous

causes of

complications in

curative treatment of

definition of

pathological anatomy of

preventive treatment of

prognosis of

symptoms of

treatment of

sub-horny

causes of

complications in

definition of

diagnosis of

extirpation of the lateral cartilage in, after Moller and Frick

extirpation of the lateral cartilage in, after Bayer

necrosis of the lateral cartilage in (cartilaginous quittor)

necrosis _of_ tendon and ligament in (tendinous quittor)

surgical shoeing in

symptoms of

treatment of

Rarefying ostitis

Recorded case of dislocation

of the os coronæ

of navicular disease in both hind-feet

of periostitis

of pyramidal disease

Rest required after neurectomy, length of

Restraint, methods of

Reunion of the divided nerve after neurectomy

Ringbone, low

Ringed hoof

causes of

definition of

treatment of

Rocker bar shoes in laminitis

Rose's treatment of canker

Sand-crack

causes of

clamp

Koster's

McGill's

Vachette's

clamping, methods of

classification of

complications in

definition of

operations for complicated

prognosis in

surgical shoeing for

symptoms of

treatment of

treatment of, by grooving the wall

treatment of, by wedging the fissure

Second interphalangeal articulation, the

Securing a hind-limb with the side-line, method of

Securing the foot to the cannon of another limb, method of

Seedy-toe

causes of

definition of

symptoms of

treatment of

Senile decay as a cause of navicular disease

Sensitive laminæ, the

Sensitive structures, gangrene of, in laminitis

Septic infection of the limb

Sequelæ of neurectomy

Serous arthritis

Shoe, bar

Charlier's

Charlier's tip

expansion

Broué's

De Fay's

Einsiedel's

Hartmann's

Smith's

for overreach

plate

rocker bar

slipper, Broué's

slipper and bar-clip, Einsiedel's

three-quarter

three-quarter bar

thinned tip

tip

with 'dropped' heel

with extended toe-piece

with extended toe-piece (Nunn's)

with heel-clip

with 'set' heel

Side-bone

causes of

definition of

diagnosis of

heredity a cause of

Smith's operation for

symptoms of

treatment of

Side-line, the

Simple acute coronitis

Simple acute periostitis

Simple coronitis

acute

chronic

Simple or cutaneous quittor

causes of

complications in

curative treatment of

definition of

pathological anatomy of

preventive treatment of

prognosis of

symptoms of

treatment of

Simple serous arthritis

Simple synovitis, acute

Smith's expansion shoe

operation for laminitis

operation for side-bone

Solar edge of the wall, expansion and contraction of the

Sole, chronic bruised

Sole, expansion and contraction of the

Sole, the

Specific coronitis

causes of

definition of

symptoms of

treatment of

Spongy hoof

definition of

symptoms of

treatment of

Stumbling after neurectomy

Sub-horny quittor

causes of

complications in

definition of

diagnosis of

necrosis of the lateral cartilage in (cartilaginous quittor)

necrosis of tendon and ligament in (tendinous quittor)

symptoms of

treatment of

surgical shoeing for

Suppurating corn

Suppuration in laminitis

Suppurative arthritis

causes of

definition of

diagnosis of

pathology of

symptoms of

treatment of

Suppurative periostitis

Suppurative synovitis

Surgical shoeing for corn

for chronic laminitis

for laminitis, acute

for sand-crack

for quittor

Symptoms

of acute simple coronitis

of brittle hoof

of canker

of chronic coronitis

of chronic laminitis

of club-foot

of contracted foot

of corn

of coronary contraction of the foot

of crooked foot

of false quarter

of flat-foot

of keraphyllocele

of laminitis

of laminitis in all four feet

of laminitis in the fore-feet alone

of laminitis in the hind-feet alone

of nail-bound

of navicular disease

of pumiced foot

of punctured foot

of pyramidal disease

of sand-crack

of seedy-toe

of side-bone

of simple chronic coronitis

of simple cutaneous quittor

of specific coronitis

of spongy hoof

of sub-horny quittor

of synovitis, chronic

of synovitis, purulent or suppurative

of synovitis, simple acute

of thrush

of weak heels

Synovitis, acute simple

causes of

treatment of

Tearing off of the entire hoof, accidental

Tendon

the extensor pedis

the flexor pedis perforans

the flexor pedis perforatus

Tendons, the

Thrush

causes of

definition of

symptoms of

treatment of

Tight-nailing

Tip-shoes

Tissue, the velvety

Tread, See Overreach

Treatment

of acute laminitis

of acute simple coronitis

of brittle hoof

of canker

of canker

Bermbach's

Hoffmann's

Imminger's

Malcolm's

Rose's

of chronic bruised sole

of chronic coronitis

of chronic laminitis

of chronic laminitis by ligaturing the digital arteries

of club-foot

of contracted feet

of contracted feet by expansion shoes

of contracted feet by operations on the horn

of corns

of coronary contraction of the foot

of crooked foot

of curved hoof

of cutaneous quittor

of false quarter

of keraphyllocele

of nail-bound

of navicular disease

of necrotic plantar aponeurosis

of periostitis

of pumiced foot

of punctured foot

of punctured navicular bursa

of pyramidal disease

of ringed hoof

of sand-crack

of sand-crack by clamping the fissure

of sand-crack by grooving the wall

of sand-crack by wedging the fissure

of seedy-toe

of side-bone

of simple chronic coronitis

of specific coronitis

of spongy hoof

of sub-horny quittor

of synovitis

of thrush

of weak heels

Use of the horse that has undergone neurectomy

Vachette's sand-crack clamp

Veins, the

Velvety tissue, the

Villate's caustic solution

Wall, the

Weak heels

causes of

definition of

symptoms of

treatment of

Wedging the fissure in the treatment of sand-crack

Wound in punctured foot, common situations of the

Wounds of the lateral cartilages

Wounds of the plantar aponeurosis

THE END