ion (see Fig. 140), afterwards exposing the lower half of the cartilage
by removing a half-moon-shaped portion of the thinned horn and underlying
sensitive laminae (see Fig. 140, _b_).

[Footnote A: Two cases of quittor successfully treated by this method are
reported by R. Paine, M.R.C.V.S., in the _Journal of Comparative Pathology
and Therapeutics_, vol. xv., p. 81.]

[Illustration: FIG. 140.--EXCISION OF THE LATERAL CARTILAGE. (AFTER MOLLER
AND FRICK.) _a_, The thinned horny wall covering the coronary cushion; _b_,
the lateral cartilage exposed by stripping off the thinned wall; _c_, the
sensitive laminae.]

This done, the external face of the cartilage is separated from the skin
of the coronet. To do this a double sage-knife is run flatwise between the
coronary cushion and the cartilage, with the convex surface of the blade
towards the skin. The knife is then passed backwards and forwards until the
necessary separation is accomplished. During these movements of the knife
a finger of the unoccupied hand should follow the knife, and guard the
coronary cushion against injury.

Following this, the inner surface of the cartilage must be also separated
from the structures lying beneath it. To this end a sage-knife (right- or
left-handed, according as to whether the anterior or posterior portion of
the cartilage is to be first removed) is again passed into the incision.
With the cutting-edge of the knife forward, it is gradually reached round
and under the hindermost end of the cartilage, and theposterior half of
the cartilage separated from underlying structures, and at the same time
excised by one clean cut forwards. Using the second sage-knife in a similar
manner, the cutting-edge this time backwards, it is reached in front of the
cartilage, whose anterior half is then excised by a careful cut backwards.
Any small portions of cartilage remaining after this are sought for with
the finger, and carefully removed by means of a scalpel and a tenaculum.

The fistulous opening or openings in the skin of the coronet should now be
thoroughly curetted, and the whole of the wound dressed as to be described
later.

In removing the anterior half of the cartilage it is highly important to
remember the close contiguity to it of the synovial membrane of the
pedal articulation. This projects as a small sac between the antero- and
postero-lateral ligaments of the joint. Risks of injury to it may be
diminished by having the foot secu