The flaps (Fig. 139, _a, a_) are now held back by tenaculæ, and the whole of the cartilage, or only the necrosed portion, carefully excised by means of right- and left-handed sage-knives. Fistulous openings in either of the flaps _a, a_ must now be carefully curetted and dressed, and the flaps allowed to fall into position. They are then sutured with carbolized gut, and the wound finally dressed as to be described later (p. 357). [Illustration: FIG. 139.--EXCISION OF THE LATERAL CARTILAGE (OLD METHOD). The wall covering the lateral cartilage first thinned and stripped off; the two flaps (_a, a_) of skin and the coronary cushion made by the vertical incision turned back. _a_, The operation flaps; _b_, the exposed cartilage; _c_, the sensitive laminæ; _d_, the coronary cushion.] _Second Method (after Holler and Frick_[A]).--These operators deem it wise to leave untouched the skin of the coronet and the coronary cushion. They therefore make their first incision along the lower border of the coronary cushion (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 laminæ (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 laminæ.] 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.