ot terminate favorably.

Luxation of the Femur.

Etiology and Occurrence.--Uncomplicated femoral luxation is of less
frequent occurrence in the horse than in the other domestic animals.
The deep cotyloid cavity renders disarticulation difficult and luxation
does not often take place. Complications that usually occur are rupture
of the round (coxofemoral) ligament or fracture of the neck of the
femur. Falls or violent strains are necessary to produce this luxation.
Goubaux is quoted by Cadiot and Almy[41] as having observed the head of
the femur in an instance wherein luxation had long existed. In this case
autopsy revealed the fact that the inner portion (two-thirds) of the
head of the femur had completely disappeared.

Luxation of the femur is observed in old emaciated animals that are
worked on slippery pavements. Occasionally, evidence of chronic luxation
of the femur is observed in the anatomical laboratory. The chronicity of
the condition is obvious when one notes the well formed articulation
which Nature provides for the head of the femur, where fracture or other
serious complications are not present.

Symptomatology.--In every case there must exist either restriction of
movement or an evident abnormal position of the leg, or both conditions
may exist at once. Also, the leg may be markedly shortened.
Manifestation of this affection varies, depending upon the character of
the luxation (position of the head of the humerus with relation to the
acetabulum). Lusk[42] cites a case of a mule which had suffered femoral
luxation. The animal was destroyed and on autopsy the head of the femur
found to be contained within a false articular cavity situated about
four inches above the acetabulum. In Dr. Lusk's case as he states it,
the following symptoms were presented: "Limb shortened and fixed in a
position of adduction. While standing the affected limb hung directly
across and in front of the opposite one; upper trochanter very
prominent; skin over hip joint very tense. The mobility of the limb was
very limited, especially in the forward direction."

Being very prominent when there is an upward luxation and less
perceptible in downward displacement, the location of the trochanter
major is an indicator of the character of the luxation with respect to
the position of the head of the femur. This variation of position
causes abnormal tenseness or looseness of the skin over the region of
the trochanter major. Rectal examin