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however, after the veterinary surgeon has passed him, the purchaser lodges
the complaint that the horse has a bad seedy-toe, which, so he is told,
must have been there for some time. In this case, culpable though he may
appear, there is every excuse for the veterinary surgeon.

Once the cavity is opened at the toe in the neighbourhood of the white
line, then diagnosis is easy. A blunt piece of wood, the farrier's knife,
or a director may be easily passed into it, sometimes as far up as
the coronary cushion (see Fig. 129). Issuing from the opening is seen
occasionally a little inspissated pus; more often, however, the dry,
mealy-looking detritus to which we have before referred. This form of the
disease we may term 'Internal Seedy-Toe.' for, plainly enough, it has had
its origin in chronic inflammatory changes in the keratogenous membrane.

[Illustration: FIG. 130. - EXTERNAL SEEDY-TOE COMMENCING AT THE PLANTAR
BORDER OF THE WALL.]

[Illustration: FIG. 131. - EXTERNAL SEEDY-TOE COMMENCING ON THE ANTERIOR
FACE OF THE WALL.]

Disease of the horn and loss of its substance may, however, also commence
from without. A report on this condition, under the title of 'External
Seedy-Toe,' is to be found in vol. xxix. of the _Veterinary Journal_, from
which we borrow Figs. 130 and 131.

In Fig. 130 it will be seen that the disease commences at the plantar
surface of the toe, and extends upwards and inwards. The same condition
may also appear anywhere between the coronet and the ground, gradually
extending into the substance of the wall, as shown in Fig. 131. According
to the writer, Colonel Nunn, the progress of the disease in this latter
case appears to be faster in a downward than in an upward direction. This,
however, is more apparent than real, as the rate of growth of the horn
downwards detracts from the progress of the disease upwards, although it
spreads over the horn at the same rate.

Before concluding the symptoms, we may again allude to the fact that,
although usually occurring at the toe, the same condition may be met with
in other positions - namely, at either of the quarters. In appearance and in
other respects it is identical with that occurring at the toe.

When the animal is lame and the existence of seedy-toe is surmised, or when
the cause of the lameness is altogether obscure, a little information may
perhaps be gathered from noting the wear of the shoe. If the animal has
been going lame for any length of time as a result of disease in the
sensitive laminæ, then the shoe will be greatly thinned at the heels, and
the toe but little worn.

_Treatment_. - As with diseased structures elsewhere, the most rational
treatment, when possible, is that of excision. The entire portion of the
wall forming the anterior boundary of the cavity is thinned down with
the rasp and afterwards removed with the knife, wholly exposing the
hypertrophied, but usually soft layer of horn covering the sensitive
structures. These hypertrophied portions are also removed, and every
particle of the dust-like detritus cleaned away. After-treatment consists
in dressing the parts with a good hoof ointment, protecting them, if
necessary, with a pad of tow and a stout bandage. It may be that the
removal of a large portion of the wall may for some time throw the animal
out of work. Acting on Colonel Fred Smith's suggestion, this may be avoided
by having made a thin plate of sheet-iron, slightly larger in circumference
than the portion of horn removed, and shaped to follow the contour of the
foot. This made, it is sunk flush with the wall by hot-fitting it, and kept
in position by several small steel screws fixed into the sound horn, just
as in the treatment for sand-crack (see p. 174). This will serve the
useful purpose of maintaining in position any dressing that may be thought
necessary, of acting as a support to the horn left on each side of the
portion removed, and of keeping the exposed structures free from dirt and
grit.

Practical points to be remembered in fitting plates of this description
to the feet are: The plate must never quite reach the shoe, or it will
participate in the concussion of progression, and so loosen the screws that
hold it in place. For the same reason, that portion of the sole adjoining
the piece of horn removed must have its bearing on the shoe relieved. The
screws holding the plate should be oiled to prevent rusting, and should
take an oblique direction in order to obtain as great a hold as possible on
the wall.

When excision is deemed unwise or unnecessary, treatment should be directed
towards maintaining the cavity in a state of asepsis. To this end it
should be thoroughly cleaned of its contents, and afterwards dressed with
medicated tow. The ordinary tar and grease stopping is as suitable as any.
This, together with the tow, is tightly plugged into the opening and kept
in position by a wide-webbed shoe. Instead of the tar stopping and the tow,
there may be used with advantage the artificial hoof-horn of Defay (see p.
152). Before using this the cavity should again be thoroughly cleaned out,
and should in addition be mopped out with ether. The latter injunction is
important, as unless the grease is thus first removed, the composition will
fail to adhere to the horn. With the cavity thus cleaned and prepared, the
artificial horn, melted ready to hand, is poured into it and allowed to
set.

In every case, no matter what else the treatment, the bearing of the horn
adjacent to the lesion should be removed from the shoe.

Whether practising the method of plugging the cavity or that of excision of
the wall external to it, attempts to quickly obtain a new growth of horn
from the coronet should be made. To further that, frequent stimulant
applications should be used. Ointment of Biniodide of Mercury 1 in 8, of
Cantharides 1 in 8, or the ordinary Oil of Cantharides, either will serve.

3. KERAPHYLLOCELE.

_Definition_. - By this term is indicated an enlargement forming on the
inner surface of the wall. In shape and extent these enlargements vary.
Usually they are rounded and extend from the coronary cushion to the sole,
sometimes only as thick as an ordinary goose-quill, at other times reaching
the size of one's finger. Often they are irregular in formation and
flattened from side to side.

[Illustration: FIG. 132. - A PORTION OF THE HORN OF THE WALL AT THE TOE
REMOVED IN ORDER TO SHOW A KERAPHYLLOCELE ON ITS INNER SURFACE.]

_Causes_. - Keraphyllocele is very often a sequel to the changes occurring
at the toe in laminitis. Probably, however, the most common cause is an
injury upon, or a crack through, the wall. It may thus occur from excessive
hammering of the foot, from violent kicking against a wall or the stable
fittings, and from the injury to the coronet known as 'tread.' It may also
occur as a sequel to complicated sand-crack, and to chronic corn.

That fissures in the wall are undoubtedly a cause has been placed on record
by the late Professor Walley, who noticed the appearance of these horny
growths following upon the operation of grooving the wall.[A]

[Footnote A: _Journal of Comparative Pathology and Therapeutics_, vol. iii,
p. 170.]

This gentleman had a large Clydesdale horse under his care for a bad
sand-crack in front of the near hind-foot, and, as the lameness
was extreme, he adopted his usual method of treatment - viz., rest,
fomentations, poulticing, and the making of the V-shaped section through
the wall, and subsequently the application of an appropriate bar shoe
to the foot, and repeated blisters to the coronet. In a short time the
lameness passed off, and the horse was put to work. A few days later the
animal met with an accident, and was killed.

On examining a section of the hoof it was found that a vertical horny ridge
corresponding to the external fissure had been formed on the internal
surface of the wall, and that a well-marked cicatrix extended upwards
through the structure of the hoof at the part forming the cutigeral groove;
furthermore, _a similar ingrowth had been taking place in the line of the
oblique incisions made for the relief of the sand-crack_.

This case has an important bearing on the operation of grooving the wall,
which operation we have several times in this work advocated for the relief
of other diseases. It teaches us that the incisions should not be carried
so completely through the horn as to interfere with and irritate the
sensitive laminæ, and so set up the chronic inflammatory condition leading
to hypertrophy of the horn.

From the position on the os pedis of the indentation made in it by the
keraphyllocele (see Fig. 133) it has been argued that pressure of the
toe-clip is a cause of the new growth. This, we should say, cannot be a
very strong factor in the causation, for, while we admit that the continual
pressure of the clip, and the heavy hammering that sometimes fits it into
position, is likely to set up a chronic inflammatory condition of the
sensitive laminæ in that region, we must still point out that the rarity
of keraphyllocele, as compared with the fact that clips are on every shoe,
does not allow of the argument carrying any great weight.

_Symptoms_. - Except under certain conditions this defect is difficult
of detection. As a rule, lameness is not produced by it. In making that
statement we are led largely by the conclusion arrived at by Professor
Walley. This observer noted the fact that ingrowths of horn such as we are
describing nearly always take place in false quarter, or after a sand-crack
has been repaired, and that they commonly occur after the operation of
grooving the wall in the manner we have just shown.

Now, we know that quite often under these circumstances the horse goes
perfectly sound. Thus, while we know that in all probability keraphyllocele
is in existence, we have ocular demonstration that the animal is quite
unaffected by it.

In some cases, however, lameness is present. During the early stages of
the growth's formation it is but slight, increasing as the keraphyllocele
enlarges. Should this be the case, other symptoms present themselves.
The coronet is hot, and tender to the touch, sometimes even perceptibly
swollen, and percussion over the wail is met with flinching on the part
of the animal. In other cases one is led to suspect the condition by
the prominence of the horn of the wall of the toe. This is distinctly
ridge-like from the coronet to the ground, while on either side of it the
quarters appear to have sunk to less than their normal dimensions. We
believe this to be an illusion, as a ridge of any size at the toe readily
gives one the impression of atrophy behind it, without this latter
condition being actually present.

Should this ridge-like formation and the accompanying symptoms of pain and
lameness occur after repair of a sand-crack, then keraphyllocele may, with
tolerable certainty, be diagnosed. When these outward signs are wanting,
however, and the true nature of our case is a matter of mere conjecture, a
positive diagnosis may still be made at a later stage - that is, when the
abnormal growth of horn reaches the sole. In this case either there is
met with when paring the sole a small portion of horn, circular in form,
distinctly harder than normal, and indenting in a semicircular fashion the
front of the white line at the toe, or solution of continuity between the
tumour and the edge of the sole and the os pedis takes place, and the
lameness resulting from the ingress of dirt and grit thus allowed draws
attention to the case.

_Pathological Anatomy_. - With the sensitive structures removed from the
hoof by maceration or other means, these growths are at once apparent. They
may occur in any position, but are usually seen at the toe, and they may
extend from the coronary cushion to the sole, or they may occupy only
the lower or the upper half of the wall. In places the tumour (or 'horny
pillar' as the Germans term it) is roughened by offshoots from it, and does
not always exhibit the smooth surface depicted in Fig. 132. Commonly, the
horn composing the new growth is hard and dense. Sometimes, however, it is
soft to the knife, and is then found to be itself fistulous in character,
a distinct cavity running up its centre, from which issues a black and
offensive pus.

In a few cases the sensitive laminæ in the immediate neighbourhood are
found to be enlarged, but in the majority of cases atrophy is the condition
to be observed. Not only are the sensitive structures found to be shrunken
and absorbed, but the atrophy and absorption extends even to the bone
itself (see Fig. 133). This latter is a result of the continued pressure of
the horny growth, in a well-marked case ending in a sharply-defined groove
in the os pedis in which the keraphyllocele rests. The fact that the softer
structures, and even the bone, thus accommodate themselves to the altered
conditions is, no doubt, the reason that lameness in many of these cases is
absent.

_Treatment_. - It is doubtful whether anything satisfactory can be
recommended. When we have suspected this condition ourselves, it has been
our practice to groove the hoof on either side of the toe, after the manner
illustrated in Fig. 120, and, at the same time, point-firing the coronet
and applying a smart cantharides blister. Certainly, after this operation,
lameness has often disappeared - whether, however, as a result of the
treatment adopted or by reason of the structures within accommodating
themselves to the condition, we would not care to say.

[Illustration: FIG. 133. - OS PEDIS SHOWING THE GROOVE IN IT CAUSED BY
ATROPHY AND ABSORPTION INDUCED BY PRESSURE OF A KERAPHYLLOCELE.]

Other writers advocate the removal of that portion of the wall to which the
tumour is attached, after the manner described on p. 182, and illustrated
in Fig. 98. This, however, should be a last resource, and should be adopted
only when weighty reasons, such as excessive and otherwise incurable
lameness, appear to demand it.

4. KERATOMA.

In our nomenclature the terms 'Keratoma' and 'Keraphyllocele' are both used
to indicate the condition we have just described. There are some, however,
who reserve the term 'Keratoma' for horny tumours occurring only on the
sole, and for that reason we draw special attention to the word here.
Keratoma may thus be used to describe what we have called keraphyllocele
directly that growth makes its appearance at the sole, and is there able
to be cut with the knife. Similar hard and condensed growths may, however,
make their appearance on the sole in other positions quite removed from the
white line, plainly being secreted by the villous tissue of the sensitive
sole, and having no connection whatever with the sensitive laminæ.
They appear as circular patches, varying in size from a shilling to a
two-shilling piece. Compared with the surrounding horn, they stand out
white and glistening, while in structure they are dense and hard, and
offer a certain amount of resistance to the knife. They are of quite minor
importance, and, beyond keeping them well pared down, need no attention.
Keratoma probably offers us the best analogy we have to corn of the human
subject.

5. THRUSH.

_Definition_. - A disease of the frog characterized by a discharge from it
of a black and offensive pus, and accompanied by more or less wasting of
the organ.

_Causes_. - The primary cause of this affection is doubtless the infection
of the horn, and later the sensitive structures, with matter from the
ground. Those factors, therefore, leading to deterioration of the horn, and
so exposing it to infection, may be considered here. Such will be changes
from excessive dampness to dryness, or _vice versâ_; work upon hard and
stony roads; prolonged standing in the accumulated wet and filth of
insanitary stables, or long standing upon a bedding which, although dry, is
of unsuitable material.

In this latter connection may be mentioned the harm resulting from the use
of certain varieties of moss litter. This we find pointed out by J. Roalfe
Cox, F.R.C.V.S.[A] Tenderness in the foot was first noticed, and, on
examination, the horn of the sole and of the frog was found to be
peculiarly softened. It afforded a yielding sensation to the finger, not
unlike that which is imparted by indiarubber, and on cutting the altered
horn it was almost as easily sliced as cheese-rind. The outer surface
being in this way slightly pared off, the deeper substance of the horn was
discoloured by a pinkish stain. The horn of the frog was in many instances
found detaching from the vascular surface, which was very disposed to take
on a diseased action, somewhat allied to canker, and became extremely
difficult to treat.

[Footnote A: _Veterinary Journal_, vol. xvi., p. 243.]

Conditions such as these, although not constituting the disease itself,
certainly lay the frog open to infection, especially if afterwards the
animal is called upon to work in the mud of the streets of a large town, or
to stand in a badly drained and damp stable.

A further cause of thrush is to be found in the condition of the frog,
brought about by contraction of the heels (see p. 118). We have already
seen that one of the most prominent factors in the causation of contraction
is the removal of the frog from the ground by shoeing, with its consequent
diminution in size and deterioration in quality of horn. This leads to
fissures in the horny covering, and favours infection of the sensitive
structures beneath. Thrush is, in fact, nearly always present in the later
stages of contracted foot.

By some thrush is believed to be but the commencement of canker. With this,
however, we do not hold. We believe both to be due to specific causes as
yet undiscovered, but that the cause of thrush is not the one operating in
canker. In arriving at this conclusion we are guided by clinical evidence.
The two conditions are quite dissimilar, even in appearance, and, while
one is readily amenable to treatment, the other is just as obstinately
resistant.

_Symptoms_. - The symptoms of thrush are always very evident. Probably the
first thing that draws one's attention to it is the stench of the puriform
discharge. The foot is then picked up and the characteristic putrescent
matter found to be accumulated in the median, and often in the lateral,
lacunæ. The organ is wasted and fissured, the horn in the depths of the
lacunæ softened and easily detachable, and portions of the sensitive frog
often laid bare.

With a bad thrush lameness is present, the frog itself is tender to
pressure, and often there is considerable heat and tenderness of the heels
and the coronet immediately above. More especially is this noticeable after
a journey.

It is, perhaps, more common in the hind-feet than in the fore, and more
often met with in heavy draught animals than in nags. The hind-feet are, of
course, more open to infection by reason of their being constantly called
upon to stand in the animal discharges in the rear of stable standings,
while it is a well-known fact that heavy animals have their stables kept
far less clean, and their feet less assiduously cared for, than do animals
of a lighter type.

In a nag-horse with thrush of both fore-feet lameness becomes sometimes
very great. The gait when first moved out from the stable is feeling
and suggestive of corns, while progress on a road with loose stones is
sometimes positively dangerous to the driver.

_Treatment_. - When this condition has arisen, as it often does, from want
of counter-pressure of the frog with the ground, this pressure must be
restored after the manner described when dealing with the treatment of
contracted foot (see p. 125) either by the use of tip or bar shoes, or by
suitable pads and stopping.

So far as direct treatment of the lesion itself is concerned, the first
step is to carefully trim away all diseased horn and freely open up the
lacunæ in which the discharge has accumulated. Good results are then often
arrived at by poulticing, afterwards followed up by suitable antiseptic
dressings. With us a favourite one is the Sol. Hydrarg. Perchlor. of Tuson,
used without dilution. Others use a dry dressing, and dust with Calomel,
with a mixture of Sulphate of Copper, Sulphate of Zinc and Alum, or with
Subacetate of Copper and Tannin.

With restoration, so far as is possible, of the frog functions, and with
careful dressing, a cure is nearly always obtained.

6. CANKER.

_Definition_. - Under this unscientific, yet expressive term, is indicated a
chronic diseased condition of the keratogenous membrane, commencing always
at the frog, and slowly extending to the sole and wall, characterized by a
loss of normal function of the horn secreting cells, and the discharge of a
serous exudate in the place of normal horn.

_Causes_. - The exact cause of canker has still to be discovered. Therefore,
before expressing an opinion as to what the _probable_ cause may be, we may
state here that such opinion can only be based upon clinical observation.
Such being the case, we are almost duty bound to give the views of older
authors before those of more modern writers.

From the mass of material ready to hand we may select the following as
serving our purpose.

The earliest opinion appears to have been that canker, as the name
indicates, was of a cancerous or cancroid nature. This was also believed by
Hurtrel D'Arboval, who looked upon canker as carcinoma of the recticular
structure of the foot. The same theory we find enunciated in the
_Veterinary Journal_ so late as 1890. Although the word 'cancer' or
'carcinoma' is not there used, the author employs the terms 'Papilloma' and
'Epithelioma' with the evident intention of expressing his belief in the
malignant nature of the disease.

Another early opinion was that the disease was a _spreading ulcer_,
gradually extending and changing the tissues which it invaded.

A further early theory, and one which if not still believed in, has died a
hard death, is the constitutional theory. This was believed in by nearly
all the older writers, and is mentioned so late as 1872 by the late
Professor Williams. In his 'Principles and Practice of Veterinary Surgery,'
he says: 'Canker is a constitutional disease due to a cachexia or habit
of body, grossness of constitution, and lymphatic temperament.' This, we
believe, is credited to-day by some, and yet, quite 100 years before the
date of the 1872 edition of Williams's work - in 1756, to be exact - we find
a veterinary writer when talking of grease (a disease, by-the-by, very
closely allied to canker) exclaiming against this habit of referring
everything which we do not rightly understand to some ill-humour of the
body. The wisdom his words contain justifies us in giving them mention
here. 'It is a very foolish and absurd Notion,' he says, 'to imagine a
Horse full of Humours when he happens to be troubled with the Grease. But
such Shallow Reasoning will always abound while Peoples' Judgments are
always superficial. Therefore, to convince such unthinking Folks, let them
take a thick Stick and beat a Horse soundly upon his Legs so that they
bruise them in several Places, after which they will swell, I dare say,
and yet be in no danger of Greasing. Now, pray, what were these offending
Humours doing before the Bruises given by the Stick?'

At the present day it is safe to assert that neither the ulcerative, the
cancerous, nor the constitutional theory is believed in widely, and, among
the mass of contrary opinions as to the cause of this disease, we may find
that even quite early many of the older writers had discarded them.

Quoting from Zundel, we may say that Dupuy in 1827 considered canker as
a hypertrophy of the fibres of the hoof, admitting at the same time that
these fibres were softened by an altered secretion; while Mercier in 1841
stated that canker was nothing more than a chronic inflammation of the
reticular tissue of the foot, characterized by diseased secretions of this
apparatus.

Saving that they make no mention of a likely specific cause, these last two
statements express all that we believe to-day. As early as 1851, however,
the existence of a specific cause was hinted at by Blaine in his
'Veterinary Art.' We find him here describing canker as a _fungoid_
excrescence, exuding a thin and offensive discharge, which _inoculates_ the
soft parts within its reach, particularly the sensitive frog and sole, and
destroys their connections with the horny covering.

The use of the word 'fungoid,' and particularly that of 'inoculate,' is
suggestive enough, and is evidence sufficient that either Blaine or his



Online LibraryHarry Caulton ReeksDiseases of the Horse's Foot → online text (page 22 of 34)