Lameness of the Horse | Page 7

bone is usually detached and the condition may then properly be called
one of fracture. In some cases of this kind recovery is tardy, because of
the difficulty in maintaining perfect apposition of the divided structures,
and reactionary inflammation is not of sufficient extent to enhance
prompt repair. In fact, some cases of this kind seem to progress more
favorably, when no attempt at immobilization of the affected member
is attempted.
If some freedom of movement is allowed, acute inflammation resulting
in nature's provisional swelling soon develops and repair is hastened
because of increased vascularity. But where luxation of phalanges
accompanies sprain, reposition and immobilization are necessary--that
is if cases are thought likely to benefit by any treatment.
Luxations--Dislocations.
Luxation or dislocation is a condition where the normal relation

between articular ends of bones has been deranged to the extent that
partial or complete loss of function results. When a bone is luxated (out
of joint), there has occurred a partial or complete rupture of certain
ligaments or tendons; or a bone may be luxated when an abnormal or
unusual elasticity of inhibitory ligaments or tendons obtains.
Luxations may be practically classified as temporary and fixed. In
temporary luxations, disarticulation is but momentary and spontaneous
reposition always results; while a fixed luxation does not reduce
spontaneously but remains luxated until reposition is effected by proper
manipulation and treatment. Fixed luxation may be of such character as
to be practically irreducible because of extensive damage done to
ligaments or cartilage. Where a complete luxation of the
metacarpophalangeal joint exists, it is probable that in most cases
sufficient injury to collateral and capsular ligaments has been done to
render complete recovery improbable, if not impossible.
Temporary luxation of the patella is a common affection of the horse
and fixed luxation of this bone also occurs. As a matter of fact, in the
horse, patellar luxation is the one frequent affection of this kind.
As a rule, complete disarticulation immobilizes the affected joint and in
most instances there is noticeable an abnormal prominence in the
immediate vicinity--in patellar luxation, the whole bone. In other
instances the articular portion only, of the affected bone is
malpositioned. Usually, luxation and fracture may be differentiated in
that there is no crepitation in luxation and more or less crepitation
exists in fracture.
It is evident, when one considers the symptomatology and nature of the
affection, that fixed luxation is usually caused by undue strain or
violent and abnormal movement of a part. Joints having the greater
freedom of movement are apt to suffer luxation more frequently.
Arthritis.
The study of arthritis in the horse is limited to a consideration of joint
inflammations which, for the most part, are of traumatic origin. Unlike

the human, the horse is not subject to many forms of specific
arthritis--tubercular, gonorrheal, syphilitic, etc.
A practical manner of classification of arthritis is traumatic and
metastatic.
Traumatic arthritis may result from all sorts of accidents wherein joints
are contused. Such cases may be considered as being caused by direct
injuries. Instances of this kind, depending on the degree of insult,
manifest evidence of injury which ranges from a simple synovitis to the
most active inflammatory involvement of the entire structure and
adjacent tissues.
The reactionary inflammation which attends a case of tarsitis caused by
a horse being kicked is a good example of the result of direct injury.
Such cases, if the contusion is of sufficient violence, result in arthritis
and periarthritis. In inactive farm horses, during cold weather, this
condition becomes chronic, swelling remains for weeks after all
lameness and pain have subsided and occasionally hyperthrophy is
permanent.
Arthritis occasioned by indirect injury, such as characterizes joint
inflammation from continuous concussion, is seen in horses that are
worked at a rapid pace on city streets or other hard road surfaces. Such
affections may be acute, as in some cases of spavin, but are usually
inflammatory conditions that do not occasion serious disturbance when
these affections become chronic. If the involvement persists with
sufficient active inflammation, there may follow erosion of cartilage
and incurable lameness. If extensive necrosis of cartilage takes place,
the attendant pain will be sufficient to cause the animal to favor the
diseased part and such immobilization enhances early
ankylosis--nature's substitute for resolution in this disease.
Wounds invading the tissues adjacent to joints, when these wounds are
of considerable extent, cause inflammation of such articulations by
contiguous extension of inflammation. As long as an injury remains
practically aseptic, or if infected and the septic process does not involve
the joint proper by direct extension, no more serious disturbance than a

simple synovitis will result. If, instead, a periarthritic inflammation is
serious or destructive in character, the type of arthritis will be
grave--even though due to an indirect cause.
Where a vulnerant body penetrates all