lar cartilages take
place. The subject becomes more lame and eventually is rendered
incapable of service.

Upon manipulation of the patellar region, one is impressed with the fact
that hyperesthesia does not exist in proportion to the pain manifested
during locomotion. In some cases a gelatinous swelling is present and
may be detected by palpating between the straight ligaments of the
patella. Williams, Hughes, Merillat, Hadley and others have directed
attention to the existence of floating masses (_corpora oryzoidea_) in
the synovial capsule of this joint in gonitis, and as with all cases of
arthritis, irreparable damage is often done the articular cartilages
during the course of the ailment.

[Illustration: Fig. 50--Chronic gonitis. The knuckling which results
from long continued inactivity of the crural muscles in chronic cases is
marked in this instance. Photo by Dr. L.A. Merillat.]

Treatment.--No effective method is as yet known which will control
this condition during its incipiency. The disease progresses, and more
or less damage is done the affected parts in the course of months or
even years in some cases before subjects are rendered hopelessly
crippled. When recognized early (before chronic gonitis exists)
aspiration of the synovia and the injection of diluted tincture of iodin
might prove beneficial in cases of synovial distension. Chronic gonitis
is considered an incurable affection and as soon as subjects manifest
evidence of distress from this condition they should by all means be
taken from work. Firing and vesication have not been productive of
beneficial results.

[Illustration: Fig. 51--Gonitis. Showing position assumed in such cases
because of pain occasioned. Photo by Dr. C.A. McKillip.]

Open Stifle Joint.

Anatomy of the Joint Capsule.--This joint capsule is thin and very
capacious. On the patella it is attached around the margin of the
articular surface, but on the femur the line of attachment is at a
varying distance from the articular surface. On the medial side it is an
inch or more from the articular cartilage; on the lateral side and
above, about half an inch. It pouches upward under the quadriceps
femoris for a distance of two or three inches, a pad of fat separating
the capsule from the muscle. Below the patella it is separated from the
patellar ligaments by a thick pad of fat, but inferiorly it is in
contact with the femerotibial capsules. The joint cavity is the most
extensive