then, the prominent points in the treatment designed for the relief of
bone spavin. Yet there are cases in which all the agencies and methods
referred to seem to lack effectiveness and fail to produce satisfactory
results. Either the rest has been prematurely interrupted or the
blisters have failed to modify the serous infiltration, or the case in
hand has some undiscernible characteristics which seem to have rendered
the disease neutral to the agencies used against it. An indication of
more energetic means is then presented, and free cauterization with the
firing iron becomes necessary.
At this point a word of explanation in reference to this operation of
firing may be appropriate for the satisfaction of any among our readers
who may entertain an exaggerated idea of its severity and possible
cruelty.
The operation is one of simplicity, but is nevertheless one which, in
order to secure its benefits, must be reserved for times and occasions
of which only the best knowledge and highest discretion should be
allowed to judge. It is not the mere application of a hot iron to a
given part of the body which constitutes the operation of firing. It is
the methodical and scientific introduction of heat into the structure
with a view to a given effect upon a diseased organ or tissue by an
expert surgeon. The first is one of the degrees of mere burning. The
other is scientific cauterization, and is a surgical manipulation which
should be committed exclusively to the practiced hand of the veterinary
surgeon.
Either firing alone or stimulation with blisters is of great efficacy
for the relief of lameness from bone spavin. Failure to produce relief
after a few applications and after allowing a sufficient interval of
rest should be followed by a second or, if needed, a third firing.
In case of further failure there is a reserve of certain special
operations which have been tried and recommended, among which those of
cunean tenotomy, periosteotomy, the division of nervous branches, etc.,
may be mentioned. These, however, belong to the peculiar domain of the
veterinary practitioner, and need not now engage our attention.
FRACTURES.
In technical language a fracture is a "solution of continuity in the
structure or substance of a bone." It ranks among the most serious of
the lesions to which the horse--or any animal--can be subject. It is a
subject of special interest to veterinarians and horse owners in view of
the fact that it occurs in such a variety of forms and subjects the
patient to much loss of time, resulting in the suspension of his earning
capacity. Though of less serious consequence in the horse than in man,
it is always a matter of grave import. It is always slow and tedious in
healing and is frequently of doubtful and unsatisfactory result.
This solution of continuity may take place in two principal ways. In the
most numerous instances it includes the total thickness of the bone and
is a complete fracture. In other cases it involves only a portion of the
thickness of the bone, and for that reason is described as incomplete.
If the bone is divided into two separate portions and the soft parts
have received no injury, the fracture is a simple one, or it becomes
compound if the soft parts have suffered laceration, and comminuted if
the bones have been crushed or ground into fragments, many or few. The
direction of the break also determines its further classification.
Broken at a right angle, it is transverse; at a different angle it
becomes oblique, and it may be longitudinal or lengthwise. In a complete
fracture, especially of the oblique kind, there is a condition of great
importance in respect to its effect upon the ultimate result of the
treatment in the fact that from various causes, such as muscular
contractions or excessive motion, the bony fragments do not maintain
their mutual coaptation, but become separated at the ends, which makes
it necessary to add another descriptive term--with displacement. These
words again suggest the negative and introduce the term without
displacement, when the facts justify that description. Furthermore, a
fracture may be intra-articular or extra-articular, as it extends into a
joint or otherwise, and, once more, intra-periosteal when the periosteum
remains intact. Finally, there is no absolute limit to the use of
descriptive terminology in the case.
The condition of displacement is largely influential in determining the
question of treatment and as affecting the final result of a case of
fracture. This, however, is dependent upon its location or whether its
seat is in one or more of the axes of the bone, in its length, its
breadth, its thickness, or its circumference. An incomplete fracture may
also be either simple or comminuted. In the latter case the fragments
are held together by the periosteum when it is intact; in that case the
fracture belongs to the intra-periosteal class. At times, also, there is
only a simple fissure or split in the bone, making a condition of much
difficulty of diagnosis.
_Causes._--Two varieties of originating cause may be recognized in cases
of fracture. They are the predisposing and the occasional. As to the
first, different species of animals differ in the degree of their
liability. That of the dog is greater than that of the horse, and in
horses the various questions of age, the mode of labor, the season of
the year, the portion of the body most exposed, and the existence of
ailments, local and general, are all to be taken into account.
Among horses, those employed in heavy draft work or that are driven over
bad roads are more exposed than light-draft or saddle horses, and
animals of different ages are not equally liable. Dogs and young horses,
with those which have become sufficiently aged for their bones to have
acquired an enhanced degree of frangibility, are more liable than those
which have not exceeded the time of their prime. The season of the year
is undoubtedly, though in an incidental way, an important factor in the
problem of the etiology of these accidents, for though they may be
observed at all times, it is during the months when the slippery
condition of the icy roads renders it difficult for both men and beasts
to keep their feet that they occur most frequently. The long bones,
those especially which belong to the extremities, are most frequently
the seat of fractures, from the circumstance of their superficial
position, their exposure to contact and collision, and the violent
muscular efforts involved both in their constant, rapid movement and
their labor in the shafts or at the pole of heavy and heavily laden
carriages.
The relation between sundry idiosyncrasies and diathesis and a liability
to fractures is too constant and well-established a pathological fact to
need more than a passing reference. The history of rachitis, of
melanosis, and of osteoporosis, as related to an abnormal frangibility
of the bones, is a part of our common medical knowledge. There are few
persons who have not known of cases among their friends of frequent and
almost spontaneous fractures, or at least of such as seem to be produced
by the slightest and most inadequate violence, and there is no tangible
reason for doubting an analogous condition in dividuals of the equine
race. Among local predisposing causes mention must not be omitted of
such bony diseases as caries, tuberculosis, and others of the same
class.
Exciting, occasional, or "efficient" causes of fracture are in most
instances external traumatisms, as violent contacts, collisions, falls,
etc., or sudden muscular contractions. These external accidents are
various in their character, and are usually associated with quick
muscular exertion. A violent, ineffectual effort to move too heavy a
load; a semispasmodic bracing of the frame to avoid a fall or resist a
pressure; a quick jump to escape a blow; stopping too suddenly after
speeding; struggling to liberate a foot from a rail, perhaps to be
thrown in the effort--all these are familiar and easy examples of
accidents happening hourly by which our equine servants become
sufferers. We may add to these the fracture of the bones of the
vertebrae, occurring when casting a patient for the purpose of undergoing
a surgical operation, quite as much as the result of muscular
contraction as of a preexisting diseased condition of the bones. A
fracture occurring under these circumstances may be called with
propriety indirect, while one which has resulted from a blow or a fall
differently caused is of the direct kind.
_Symptoms._--We now return to the first items in our classification of
the varieties of fractures for the purpose of bringing them in turn
under an orderly review, and our first examination will include those
which belong to the first category, or the complete kind. Irregularity
in the performance of the functions of the apparatus to which the
fractured bone belongs is a necessary consequence of the existing
lesion, and this is lameness. If the broken bone belongs to one of the
extremities, the impossibility of the performance of its natural
function in sustaining the weight of the body and contributing to the
act of locomotion is usually complete, though the degree of disability
will vary according to the kind of fracture and the bone which is
injured. For example, a fracture of the cannon bone without
displacement, or of one of the phalanges, which are surrounded and
sustained by a complex fibrous structure, is, in a certain degree, not
incompatible with some amount of resting on the foot. On the contrary,
if the shank bone, or that of the forearm is the implicated member, it
would be very difficult for the leg to exercise any agency whatever in
the support of the body, and in a fracture of the lower jaw it would be
obviously unreasonable to expect it to contribute materially to the
mastication of feed.
It seldom happens that a fracture is not accompanied with a degree of
deformity, greater or less, of the region or the leg affected. This is
due to the exudation of the blood into the meshes of the surrounding
tissues and to the displacement which occurs between the fragments of
the bones, with subsequently the swelling which follows the inflammation
of the surrounding tissues. The character of the deformity will mainly
depend upon the manner in which the displacement occurs.
In a normal state of things the legs perform their movements with the
joints as their only centers or bases of action, with no participation
of intermediate points, while with a fracture the flexibility and motion
which will be observed at unnatural points are among the most strongly
characteristic signs of the lesion. No one need be told that, when the
shaft of a limb is seen to bend midway between the joints, with the
lower portion swinging freely, the leg is broken. There are still some
conditions, however, in which the excessive mobility is not easy to
detect. Such are the cases in which the fracture exists in a short
bone, near a movable joint, or in a bone of a region where several short
and small bones are united in a group, or even in a long bone the
situation of which is such that the muscular covering prevents the
visible manifestation of the symptom.
If the situation of a fracture precludes its discovery by means of this
abnormal flexibility, other modes of detection remain. There is one
method which is absolute and positive and which can be applied in by far
the most, though not in all cases. This is crepitation, or the peculiar
effect which is produced by the friction of the fractured surfaces one
against another. Though discerned by the organs of hearing it can
scarcely be called a sound, for the grating of the parts as the rubbing
takes place is more felt than heard; however, there is no mistaking its
import in cases favorable for the application of the test. The
conditions in which it is not available are those of incomplete
fracture, in which the mobility of the part is lacking, and those in
which the whole array of phenomena are usually obscure. To obtain the
benefit of this pathognomonic sign requires deliberate, careful, and
gentle manipulation. Sometimes the slightest of movements will be
sufficient for its development, after much rougher handling has failed
to discover it. Perhaps the failure in the latter case is due to a sort
of defensive spasmodic rigidity caused by the pain resulting from the
rude interference.
More or less reactive fever is a usual accompaniment of a fracture.
Ecchymosis in the parts is but a natural occurrence, and is more easily
discovered in animals possessing a light-colored and delicate skin than
in those of any other character.
There are difficulties in the way of the diagnosis of an incomplete
fracture, even sometimes when there is a degree of impairment in the
function of locomotion, with evidences of pain and swelling at the seat
of lesion. There should then be a careful examination for evidences of a
blow or other violence sufficient to account for the fracture, though
very often a suspicion of its existence can be converted into a
certainty only by a minute history of the patient if it can be obtained
up to the moment of the occurrence of the injury. A diagnosis ought not
to be hastily pronounced, and where good ground for suspicion exists it
ought not to be rejected upon any evidence less than the best. We too
often read of serious and fatal complications following careless
conclusions in similar cases, among which we may refer to one instance
of a complete fracture manifesting itself in an animal during the act of
rising in his stall after a decision had been pronounced that he had no
fracture at all.
Fractures are of course liable to complications, especially those which
are of a traumatic character, such as extensive lacerations, tearing of
tissues, punctures, contusions, etc. Unless these are in communication
with the fracture itself the indication is to treat them simply as
independent lesions upon other parts of the body. A traumatic emphysema
at times causes trouble, and abscesses, more or less deep and diffused,
may follow. In some cases small, bony fragments from a comminuted
fracture, becoming loose and acting as foreign bodies, give rise to
troublesome fistulous tracts. A frequent complication is hemorrhage,
which often becomes of serious consequence. A fracture in close
proximity to a joint may be accompanied with dangerous inflammations of
important organs, and induce an attack of pneumonia, pleurisy,
arthritis, etc., especially if near the chest; it may also cause
luxations, or dislocations. Gangrene, as a consequence of contusions or
of hemorrhage or of an impediment to the circulation, caused by
unskillfully applied apparatus, must not be overlooked among the
occasional incidents; nor must lockjaw, which is not an uncommon
occurrence. Even founder, or laminitis, has been met with as the result
of forced and long-continued immobility of the feet in the standing
posture, as one of the involvements of unavoidably protracted treatment.
When a simple fracture has been properly treated and the broken ends of
the bone have been securely held in coaptation, one of two things will
occur. Either--and this is the more common event--there will be a union
of the two ends by a solid cicatrix, the callus, or the ends will
continue separated or become only partially united by an intermediate
fibrous structure. In the first instance the fracture is consolidated or
united; in the second there is a false articulation, or pseudarthrosis.
The time required for a firm union or true consolidation of a fracture
varies with the character of the bone affected, the age and constitution
of the patient, and the general conditions of the case. The union will
be perfected earlier in a young than in an adult animal, and sooner in
the latter than in the aged, and a general healthy condition is, of
course, in every respect, an advantage.
The mode of cicatrization, or method of repair in lesions of the bones,
has been a subject of much study among investigators in pathology, and
has elicited various expressions of opinion from those high in
authority. The weight of evidence and preponderance of opinion are about
settled in favor of the theory that the law of reparation is the same
for both the hard and the soft tissues. In one case a simple exudation
of material, with the proper organization of newly formed tissue, will
bring about a union by the first intention, and in another the work will
be accompanied with suppuration, or union by the second intention, a
process so familiar in the repair of the soft structures by granulation.
Considering the process in its simplest form, in a case in which it
advances without interruption or complication to a favorable result, it
may probably be correctly described in this wise:
On the occurrence of the injury an effusion of blood takes place between
the ends of the bone. The coagulation of the fluid soon follows, and
this, after a few days, undergoes absorption. There is then an excess of
inflammation in the surrounding structure, which soon spreads to the
bony tissue, when a true ostitis is established, and the compact tissue
of the bone becomes the seat of a new vascular organization, and of a
certain exudation of plastic lymph, appearing between the periosteum and
the external surface of the bone, as well as on the inner side of the
medullary cavity. After a few days the ends of the bone thus surrounded
by this exudate become involved in it, and the lymph, becoming vascular,
is soon transformed into cartilaginous, and in due time into bony,
tissue.
Thus the time required for the consolidation of the fractured segments
is divisible into two distinct periods. In the first they are surrounded
by an external bony ring, and the medullary cavity is closed by a bony
plug or stopper, constituting the period of the provisional callus. This
is followed by the period of permanent callus, during which the process
of converting the cartilaginous into the osseous form is going forward.
The restorative process is sooner completed in the carnivorous than in
the herbivorous tribes. In the former the temporary callus may attain
sufficient fineness of consistency for the careful use of the limb
within four weeks, but with the latter a period of from six weeks to two
months is not too long to allow before removing the supporting apparatus
from the limb.
This, in general terms, represents the fact when the resources of nature
have not been thwarted by untoward accidents, such as a want of vigor in
the constitution of the patient or a lack of skill on the part of the
practitioner, and especially when, from any cause, the bony fragments
have not been kept in a state of perfect immobility and the constant
friction has prevented the osseous union of the two portions. Failures
and misfortunes are always more than possible, and instead of a solid
and practicable bony union the sequel of the accident is sometimes a
false joint, composed of mere flexible cartilage, a poor pseudarthrosis.
The explanation of this appears to be that, first, the sharp edges of
the ends of the bone disappear by becoming rounded at their extremities
by friction and polishing against each other. Then follows an exudation
of a plastic nature which becomes transformed into a cartilaginous layer
of a rough, articular aspect. In this bony nuclei soon appear, and the
lymph secreted between the segments thus transformed, instead of
becoming truly ossified, is changed into a sort of fibrocartilaginous
pouch, or capsular sac, in which a somewhat albuminous secretion, or
pseudo-synovia, permits the movement to take place. Most commonly,
however, in our animals, the union of the bony fragments is obtained
wholly through the medium of a layer of fibrous tissue, and it is
because the union has been accomplished by a ligamentous formation only
that motion becomes practicable.
_Prognosis._--The prognosis in a case of fracture in an animal is one of
the gravest vital import to the patient, and therefore of serious
pecuniary concern to his owner. The period has not long elapsed when to
have received such a hurt was quite equivalent to undergoing a sentence
of death for the suffering animal, and perhaps to-day a similar verdict
is pronounced in many cases in which the exercise of a little mechanical
ingenuity, with a due amount of careful nursing, might secure a contrary
result and insure the return of the patient to his former condition of
soundness and usefulness.
_Treatment._--Considered per se, a fracture in an animal is in fact no
less amenable to treatment than the same description of injury in any
other living being. But the question of the propriety and expediency of
treatment is dependent upon certain specific points of collateral
consideration.
(1) The nature of the lesion is a point of paramount importance. A
simple fracture occurring in a bone where the ends can be firmly secured
in coaptation presents the most favorable condition for successful
treatment. If it is that of a long bone, it will be the less serious if
situated at or near the middle of its length than if it were in close
proximity to a joint, from the fact that perfect immobility can rarely,
in the latter case, be secured without incurring the risk of subsequent
rigidity of the joint.
A simple is always less serious than a compound fracture. A comminuted
is always more dangerous than a simple, and a transverse break is easier
to treat than one which is oblique. The most serious are those which are
situated on parts of the body in which it is difficult to obtain perfect
immobility, and especially those which are accompanied with severe
contusions and lacerations in the soft parts; the protrusion of
fragments through the skin; the division of blood vessels by the broken
ends of the bone; the existence of an articulation near the point to
which inflammation is liable to extend; the luxation of a fragment of
the bone; laceration of the periosteum; the presence of a large number
of bony particles, the result of the crushing of the bone--all these are
circumstances which discourage a favorable prognosis, and weigh against
the hope of saving the patient for future usefulness.
Fractures which may be accounted curable are those which are not
conspicuously visible, as those of the ribs, where displacements are
either very limited or do not occur, the parts being kept in situ by the
nature of their position, the shape of the bones, the articulations they
form with the vertebra, the sternum, or their cartilages of
prolongation; those of transverse processes of the lumbar vertebra;
those of the bones of the face; those of the ilium; and that of the
coffinbones. To continue the category, the following are evidently
curable when their position and the character of the patient contribute
to aid the treatment: Those of the cranium, in the absence of cerebral
lesions; those of the jaws; of the ribs, with displacement; of the hip;
and those of the bones of the leg in movable regions, but where their
vertical position admits of perfect coaptation.
On the contrary, a compound, complicated, or comminuted, fracture, in
whatever region it may be situated, may be counted incurable.
In treating fractures time is an important element and "delays are
dangerous." Those of recent occurrence unite more easily and more
regularly than older ones.
(2) As a general rule, fractures are less serious in animals of the
smaller species than in those of more bulky dimensions. This influence
of species will be readily appreciated when we realize that the
difficulties involved in the treatment of the latter class have hardly
any existence in connection with the former. The difference in weight
and size, and consequent facility in handling and making the necessary
applications of dressings and other appliances for the purpose of
securing the indispensable immobility of the parts, and usually a less
degree of uneasiness in the deportment of the patients are
considerations in this connection of great weight.