When a single bone is affected, the disease recent, and the troubles
not too great, treatment may be followed by recovery. (See Caries and
Necrosis.) With diffuse osteo-myelitis, when specially several bones are
affected, it is useless to undertake treatment.
CARIES — SUPPURATIVE OSTEOMYELITIS. 459
V.
CARIES— SUPPURATIVE OSTEOMYELITIS.
This affection, known in veterinary practice under the name of canes, is
•essentially characterized by the interstitial suppuration of the bony sub-
stance, accompanied with necrobiotic manifestations and terminating with
the complete destruction of the invaded bony structure.
Promoted by pyogeneous microbes, specially the staphylococcus aureus
and albus, it corresponds to the traumatic osteomyelitis of human surgery
— the term cai-ies being applied specially to bony tuberculosis by surgeons.
Peri-osseous suppurations may be complicated with caries. Bony
wounds made by soiled instruments generally bring on the same result.
In animals, as well as in man, caries may be related to a general
morbid state ; it then may appear without apparent producing cause.
Anyhow it is possible for the micro-organisms to be carried in bones by
the circulation : Rodet and Jacoulay have produced osteomyelitis and
bony suppuration by injecting cultures of staphylococci in the veins of
rabbits. But, in the majority of cases, caries is due to local causes. The
superficiality and the porosity of bones predispose them to it. In horses,
the last phalanx, on account of its structure, the frequency of the trauma-
tisms which affect it and the infectious processes that follow, furnishes the
very great majority of the cases of caries met with in our practice. The
.navicular bone, the spinous processes of the withers, the maxillaries, are
also frequently affected.
The treatment must have for object the rapid and complete elimination
of the invaded bony structure, and the transformation of the morbid
center in a simple bony wound, whose repair will go on rapidly in the
â– ordinary way. There are two methods to choose : in one, exclusively
surgical, the entire carious part is excised with the sharp instrument ; the
other, more conservative, consists in transforming the carious part into a
true chemical scar analogous to the splinter of necrosis, likely to promote
as it does, on its periphery, a moderate inflammatory process sulificient for
its elimination. By this second mode, one, as Oilier says, attempts to
" necrotize " the carious bone — to give it artificially the physical and
•chemical characters of the bone, necrosed spontaneously.
The use of either of these processes is dependent on various circum-
stances, specially the seat of the caries and the disorders it has given
rise to. In all cases, however, it is indicated to interfere as soon as
possible.
460 VETERINARY SURGICAL THERAPEUTICS.'
The treatment of caries by actual cauterization goes back to old time ;;
it was freely used by old hippiatres, who had borrowed it from human
surgery. Lafosse, who had seen many of its good results, said : " The red
iron makes a non-contagious eschar and the suppuration, which follows its
application, is a true knife with which nature separates the diseased from
the healthy tissue." Cauterization not only makes eschars of the carious
parts, but it creates in the surrounding region a true, eliminating and
cicatricial inflammation. Repeated cauterization has often been used
uccessfully in costal caries, which had resisted other forms of treatment.
The operation must be done according to some rules : when the disease
affects bones situated in the neighborhood of important organs (cranium,
ribs, extremities of long bones), the cauterization must be done slight for
a few moments, done at several seatings, one or two days apart, to such
effect that the heat would not penetrate as far as the organs that these
bones cover or protect ; spongy bones should be burnt for a longer time
than those that are dry or compact, on account of the great quantity of
fluid which, escaping for the first, rapidly put the heat out, and also be-
cause caries affects them more deeply.
A great number of chemical caustics have been advocated against
caries ; emetic (St. Cyr), chloride of zinc, nitrate of silver, more or less
diluted mineral acids, specially sulphuric (Pollock, Mollereau). We do not
like this treatment. Not only are those agents powerless to arrest the
caries, but they may give rise to severe disorders in the soft parts which
cover the diseased bone.
Every time that one wishes to interfere directly and easily upon the dis-
eased bone, he must proceed with the removal of the carious tissue. This
is the way that all caries of the third phalanx must be operated. There,
the operation consists in exposing the tegumentary membrane that en-
velops the phalanx, in freely excising all portions of the velvety and
podophyllous tissues, which are gangrenous or on the road to mortification ;
then, with a sage knife, the drawing knife or a curette, remove layer by
layer the part of bone that is dead, until the surface exposed gives evi-
dence of its vitality and perfect integrity by its normal resistance, its
rutilant coloration on exposure to the air, through the bloody oozing which
comes from the areolae of the spongy tissue all over its surface. When
this presents still in some points a bony tissue with a brown, purplish or
yellow-greenish color and if pressure brings on the oozing of some traces
of pus or sanious fluid, the curette must hollow all these points, until
sound spongy tissue is reached ; it is better to scrape some of this than to
have the smallest portion of diseased tissue left behind. Often, after
trying to preserve a thin layer of the os pedis, one is obliged, two or three
days later, to make a large cut in the foot, remove a wide piece of the
NECROSIS. 461
tegumentary covering and cut deeply into the phalanx. It has been rec-^
ommended to limit the scraping of the carious part inside the limits of
its extent, and to complete the operation by the application, on the dis-
eased part, of a small wadded tent impregnated with caustic fluid, such
as sulphuric acid diluted to the third or the quarter. These caustic solu-
tions were supposed to have the great power of limiting their action to
the extent of the altered structures. We have already stated how erroneous
this belief is. It is better to be done with the caries at once, to scrape
down to healthy tissue and apply an antiseptic dressing. In cases of
caries of the third phalanx, when, exceptionally, the podophyllous and
velvety tissues are sound, they must be respected : their preservation is
of the utmost importance for the repair of the new hoof. In such in-
stances, the fragments of the membrane corresponding to the caries must
be carefully dissected to expose the diseased bone (Bouley). In other cir-
cumstances, the periosteum must be carefully saved. It should be sepa-
rated carefully from the bone, so as to preserve it and have it co-operate in
the formation of new bone. Upon the saving of the internal cellular layer
of the periosteum depends, indeed, the regeneration more or less rapid and
perfect of the destroyed bone ; daily practice in human surgery proves it
sufficiently. Very extensive alterations may necessitate amputation in
small animals. The special rules of the treatment of caries in some regions
are indicated in the chapters relating to those affections. (See Vol. II.)
The general indications, so important in the caries of man, are, however,
secondary to all animals. Yet in dogs there are cases where it is ad-
vantageous to administer cod liver oil, quinine, Fowler solution or alka-
lines.
VI.
NECROSIS.
Necrosis, dry caries, dry gangrene of bones has a complicated etiology..
In animals traumatism is a great producing cause. Bones of the extrem-
ities are, on that account, most exposed; the radius and the tibia are those
where it is generally observed, by the fact of the frequency of the con-
tusions to which they are exposed and their want of protection on their
internal face ; phalanges, scapula, sternum, maxillary, offer also frequent
examples.*
Several diseases, distemper among them, are sometimes accompanied with
1 An unusual case of necrosis of the dorsal vertebrae is reported by F. Allen, D. V. S.,
"vshich gave rise to progressive paraplegia in an old horse, which ended fatally, and at
the post-mortem of which the annular portion of the 7th, 8th, 9th and loth dorsal
■vertebrae were more or less necrosed. — Amer. Vet. Review, vol. 8, page 360.
462 VETERINARY SURGICAL THERAPEUTICS.
bony lesions, bringing with them more or less extensive mortification ; lead
and phosphorus poisoning must have the same nocive action in animals
as in man, but facts to this effect are wanting.
The size of the sequestrum varies much. Sometimes it is but a very-
small piece of bone, or even small fragments (parcellar necrosis) ; in some
cases (panosteitis) mostly the whole bone is affected. Sequestra are
exposed or iiiz'aqinated. The museum of Alfort contains several specimens
of invaginated scapula. We have seen two beautiful ones in Lyon. On
a horse affected with comminuted fracture of the scapula, Chuchu extracted
first a few splinters, then after two or three months, a sequestrum from the
anterior angle of the bone. In the observation of Barrier and Gervais,
it was a mare which had received a kick on the anterior border of the
right shoulder, about twelve centimeters above the shoulder joint ; a blister
was applied and the patient put to rest ; the lameness, first slight, increased
little by little ; extremely serious symptoms became manifest, the animal
dropped in the slings and was killed. The necrosed scapula was covered
with an osteo-cartilaginous envelope of new formation. Jacquot has re-
ported the case of a yearling colt, convalescent from distemper, which
received a kick on the superior part of the forearm ; the fistulous wound
that followed was treated by blistering and antiseptic injections ; an
enormous swelling occurred with other numerous fistulas from which
escaped an abundant suppuration. He was destroyed. At post-mortem
an extensive necrosis of the radius was found with sequestration of the
necrosed portion.
If all denuded bony surface is predisposed to necrosis, infection
plays with it the primordial part. A piece of bone, deprived of cir-
culation, but aseptic, is tolerated by the tissues ; it does not promote
suppuration, it may become grafted, and the characters of this asep-
tic necrosis are very different from those of infectious mortifications.
Therefore, as soon as a bone is exposed, isolated from its periosteum,
it must, after minute disinfection, be covered with an antiseptic prep-
aration (iodoformed, phenicated or boricated vaseline), which prevents
its desiccation and protects it from external agents.
When mortification exists, the treatment includes four indications; ist,
hasten the limitation of the necrosis ; 2d, favor the elimination; 3d, pre-
vent infections ; 4th, activate the repairs. When necrosis has affected
but a very limited and superficial surface, as is seen frequently with some
bones, simple antiseptic injections are sufficient to prevent all complica-
tions ; by the local reaction alone, the sequestrum is eliminated and the loss
of substance is rapidly filled up. In bygone days, escharotics and caus-
tics were frequently used ; some exclusively employed tincture of iodine
or Villate solution in injections through the fistula ; others cauterized it
NECROSIS.
463
"with the red iron. (Fig. 100.)^ To-day, phenicated water, liquor of Van
Svvieten, chloride of zinc (10 p. 100) are mostly used. Though the slough-
ing of the sequestrum takes place slowly, there is no need to remove it
with sharp instruments. Leave the work to nature. Often the gouge or
the dressing knife would remove too little or too much of the tissue.
However, if it was feared that the inflammation might spread to other
important organs, it would be advantageous to excise the dead part and
Fig. 100. — Necrosis of the scapula. S, sequestrum. (Specimen of the Afort School.)
Stop only when healthy tissue is reached, easily recognized by its aspect
and the blood that oozes over the section. With these exceptions, the
disjunction must be left to take place spontaneously.
During the time that the separation between the dead and the living
tissue goes on, some special cares are necessary to avoid complication.
Abscess should be open, purulent undermining freely cut at dependent
1 In the museum of the American Veterinary College there is a specimen similar
to that represented in Fig. 100, the entire scapula being enveloped and moving loose
in it.
-464 VETERINARY SURGICAL THERAPEUTICS.
parts and drained ; frequent antiseptic irrigations will prevent purulent
resorption.
As soon as delimitation is operated the pus changes aspect ; from
serous, it becomes whitish, thicker ; at that time, if the sequestrum
is isolated and not incarcerated, nothing is easier than to extract it.
After free incising, it is taken hold of with forceps and brought outwards.
— PhaIa7igectoniy has been performed by Garcin (1834) on a mule, suf-
fering with a nail in the foot ; the os pedis, entirely necrosed, was held
only by "a very small ligamentous band," it was removed entirely; after
four months the animal " was returned to work, and though lame, was
able to do it for two years after.'' In a heifer suffering with nail in the
foot with necrosis, Delafond, in 1838, performed sesamoidectonty.
^' Nineteen days after, there was scarcely any lameness, the animal re-
covering completely."
The operation is also easy when the bone, though invaginated in a thick
"bony box, communicates with the exterior by a large opening, through
Avhich it may pass ; it can be secured and brought out with forceps.
When the cloaca are narrow, recovery is more difficult ; it necessitates
sequestrotomy .or necrotomy. If the sequestrum is left to itself, suppura-
tion becomes abundant and the patient becomes weak; but hasty inter-
ference is dangerous ; the bony envelope must be of a sufficient strength
not to break during the manipulation of the operation — a point of great
importance, should it occur on bones of an extremity.
Interference decided upon, the soft parts are divided, in saving blood
vessels and nerves, and the incision connecting all fistulous tracts together,
as much as possible. The region being chronically inflamed, the hemorrhage
is always abundant ; esmarchisation, or at least a rubber cord placed at
the upper part of the leg, are good precautions. Reaching the bone, the
periosteum is dissected loose, and then, with the trephine or the gauge
and mallet, a piece of bone is removed, wide enough to permit the ex-
ploration of the suppurating cavity. Sometimes one meets with a dia-
physis entirely necrosed, then he is obliged to enlarge the opening, " to
remove the cover of the bony coffin where lays the dead diaphysis." In
such cases, it is prudent to divide the sequestrum, so as not to reduce to
excess the resistance of the protective envelope. The cavity is curetted,
irrigated, plugged with iodoformed gauze ; antiseptic dressings favor the
complete repair of the trauma. One can conceive the disturbances that
such operations demand and how long inust recovery be. In very young
subjects, where repairing power is great, success is possible ; but often
lameness remains, incompatible with economical exploitation of animals.
For this reason, in large animals, abstention is the rule, even when the
extraction of the sequestrum is easy.
EXOSTOSIS. 465
To avoid the always serious operation of sequestrotomy, chemical agents
bave been recommended to obtain the dissolution of the necrosed tissue.
Some twenty years ago, Pollock recommended in man, the use of sulphuric
acid mixed with its weight of water. Painted over with this solution, the
sequestrum becomes soft, brittle, it is partly dissolved and the rest is elim-
inated by suppuration. Marcacci recommended perchloride of iron to
activate the delimitation. For him, this agent irritated the healthy living
structure and promoted the formation of numerous capillary vessels which
soon isolated the necrosed from the living parts. Morris more recently has
advanced another process. The fistulas being enlarged with the knife, he
injects a solution of muriatic acid (2 or 3 p. 100), which dissolves the
calcareous elements of the necrosed bones without acting on the living ones.
A chlorhydropepsic solution thus used and composed of : muriatic acid,
16 drops; pepsine, 2 grammes; distilled water, 120 grammes, digests the
caseous and fatty detritus remaining of the decalcified bone. In using
alternately both solutions, the sequestrum is rapidly destroyed and re-
covery obtained.
In preference to these chemical treatments, the more rapid and more
certain operating methods are generally in use.
During all the time of the treatment, the patient should receive gener-
â– ous diet, stimulants and tonics. The progress of the disease should be
•carefully watched, and the complications likely to occur avoided.
VII.
EXOSTOSIS.
Result of a productive osteo-periostitis, exostosis are particularly fre-
<iuent in the extremities, where many receive special names. In a gen-
eral way, the name of exostosis is given to well defined bony tumors ; that
of periosiosis to diffused neoformation ; that of hyperostosis to the in-
crease in size of a bone in its dimensions. In the point of view of
their structure they are divided into: 1st, e^urnate^ exostosis, contain-
ing no blood vessels; 2nd, compact exostosis, formed of dense tissue ;
3d, spongy exostosis, made of areolar tissue. In relation to their seat,
they are epiphysar, developed on the surface of bones ; parenchymatous^
formed in the thickness of the bone ; enostosis, occupying the medullary
, canal.
For a long time, observers have noticed that exostosis developed spe-
cially on a level with the surface of insertion of the principal ligaments ;
osselets, on the points of attachment of lateral or interosseous ligaments ;
splints, on the line of interosseous fibres ; ringbones of the pasterns, near
466 VETERINARY SURGICAL THERAPEUTICS.
the point of ligamentous insertions. Exostosis of the rachidian column
take place also at the insertions of the inferior common vertebral, in-
terspinal or articular ligaments (Goubaux and Barrier). Whatever may
be the power of a muscle, exostosis are almost never found at the point
of insertion of its terminal tendons. The few exceptions to thio rule are
met with in tendinous cords, which on some parts of their course play the
part of ligaments. These facts are easily explained, if it is thought that the
ligaments of extremities have to support the reactions from the ground,
while tendons stand only the more or less powerful actions of the muscles
they terminate, which is far inferior to the great traction that the whole
mass of the body, sometimes loaded heavily or animated by rapid gait,
gives to the agents having for duty to hold the articular surface in rela-
tion (Barrier). Traumatisms are frequent causes of exostosis. Violent
pressures, surrounding inflammations, youth, heredity, play a more or
less important part in their development. Let us mention the exostosis
called ostcogenical, appearing without evident cause, and among them, ia
particular, the cranian exostosis met often in bovines (Goubaux).
â– The manifestations given by exostosis vary according to their seat, age
and size. Renault has seen in a horse two bony growths of the frontal
portion of the cranian cavity which gave rise to immobility, by pressure
'upon the brain. Neyraud has mentioned a case of paraplegia due to
strangulation of the spinal cord by an intra-rachidian exostosis. Bony
tumors of the pelvis, often following fractures, may wound or perforate
the bladder or the intestines (Bouley Jr., Coulbaux, Patu) or interfere
considerably with parturition (Favre).
But the most frequent and most important exostosis, from the point of
view of practice, are those that develop on the bones of the extremities
of our animals used as motors. During the whole course of the osteitis
which prepare and develop them, they may interfere with tendons, disturb
the regular functions of joints, press upon blood-vessels or nerves.
After Hunter and Cooper, some authors, to make bony tumors disap-
pear, have recommended the administration of diluted mineral acids —
a poor way which has never given good results. If success has been
claimed, it must be attributed to the evolution of the organism alone.
The existence in young horses of bony growths which are temporary, and
are resorbed with age, is well known. Many practitioners, Liard and
Gillibert among them, have mentioned cases of spontaneous disparition of
these exostosis. In general, however, those tumors are tenacious. To
obtain their resolution, blisters and alteratives have been recommended.
Tincture of iodine, charge of Lebas, that of Girard, have had their day.
To-day, cantharidis blister, that of mercury, red ointment, are the prepara-
-tions most in use. Bichromate of potassae, tried first by Neff, Fcelen, has-
EXOSTOSIS. 467
given good results to Schmid, Peuch, Lamouroux. It is made in proportion
of I to 16, }i, }{, Yi. " The bony tumors, which Uke ringbones and callous
spavin, frequently give rise to tenacious lameness, demand friction, repeated
often with ointment, }^ io yi ... . If one uses an ointment to the
i6th, 12th or 8th, and rubs it slightly a few days apart, the treatment
will leave no mark. If, on the contrary, a stronger ointment is used, if
the frictions are frequent and severe, the bulbs of the hair are destroyed by
the caustic, and the animal more or less blemished. The slough of the
eschar is always slow ; sometimes even, when the quantity of bichromate is
very small, it falls off unnoticed. In some cases, however, there is forma-
tion of a small quantity of pus." *
The numerous topics with secret composition, liquid fires, liniments,
ointments, pomatums, praised against bony blemishes, have no superiority
over the mercurial blister or ointment of biodine, which remain the agents
most commonly used. There is some advantage to percute the tumor
slightly with the plessimeter before applying the blisters. Flagellation and
massage, already used in old times, have again been recently advocated by
Felizet. Pressure over the tumor is a method of Lafosse, reintroduced by
MoUer. It is seldom used. When blistering has failed, firing is indicated.
It has been advocated under all its forms : in superficial points, lines, deep
points. We prefer this last mode, which reaches the bone itself and gives
rise in it to high inflammation ; we pierce the skin through with one or
two strokes of the cautery, penetrate into the bony tumor and cover the
cauterized surface with a coat of blister. Praise of the penetrating
points needs not to be made. Rey, Leblanc, Andre, Lavendhomme, Fou-
cher, Abadie, have proclaimed the excellence of the method.
But there are cases where cauterization fails : it is for them that the
bistouri has been recommended. Sewel, professor in the veterinary col-
lege of London, invented, to produce the resorption of exostosis, the
division of the periosteum on their surface. This operation — perios/oto?ny —
has been used but little in France. To perform it a kind of bistouri having
a strong blade with convex sharp edge and blunt point is used ; at the base
of the exostosis an incision is made in which the periostotome is engaged ;
pushed flat-wise under the skin, until it reaches the superior border of the
tumor, the sharp edge is then turned on its surface and the periosteum is
divided. According to Sewel, only a slight inflammation follows, and after
ten or fifteen days the animal can resume its work. Reynal has obtained
no good results with this operation. Bouley found it advantageous for
subcutaneous growths, as splints, but " it is not the same with those
situated under a complex fibrous apparatus, as ringbones and spavins,
"which cannot be interested in their thickness without having first divided
1 Peuch, Journal de Med. Vet., 1868, p. 440.
468 VETERINARY SURGICAL THERAPEUTICS.
the thick coat of tissues, rebel to the inflammation, wh ich covers them ;
and besides that, for certain ringbones as for some spavins, the im-
mediate neighborhood of the articulations is one of the most important
circumstances which make us reject the idea of the application of peri-