Definition.—­A fistulous wound of the foot, usually opening at the coronet, and variously complicated according to the structures invaded by its contained pus.  For the reason that quittor is in every-day veterinary nomenclature usually associated with necrosis or other abnormal condition of the lateral cartilage, we include its description in this chapter.

Classification.—­It has been customary with Continental authors to classify quittor according to the extent and position of the diseased process.  There were thus distinguished: 

(a) The Simple or Cutaneous Quittor, in which had occurred nothing more than necrosis of a portion of the coronary skin and the structures immediately underlying it—­that is, the superficial portion of the coronary cushion.

(b) The Tendinous Quittor, in which not only the immediately subcutaneous tissues were attacked, but also portions of tendon and of ligament.

(c) The Sub-horny Quittor, in which the diseased process had invaded the deeper portions of the coronary cushion, and continued a downward course until the laminal tissue below the upper margin of the wall was involved, or any other case, no matter what the starting-point, in which pus existed within the horny box and was discharging itself by a fistulous opening.

(d) The Cartilaginous Quittor, in which a portion of the lateral cartilage had become attacked and rendered necrotic.

We believe that—­in this country, at any rate—­the word ‘quittor’ is usually held to indicate one or other of the two latter conditions, and probably the last of these; and that the two first are held of small account, or hardly of sufficient gravity to allow of the word ‘quittor’ being applied to them.  In fact, by defining quittor as a ‘fistula,’ or little pipe, we have ourselves already indirectly restricted the use of the word to the two latter conditions, for in those varieties known as Simple or Cutaneous and Tendinous, the wound is generally broad and open, or, at any rate, superficial, and can scarcely be strictly described as ‘fistulous.’  In the two latter, however, a true fistula exists.  These, however, have only one essential difference, and that consists simply in the position of the lesion and the structures it has attacked.  In the main the symptoms will be the same, the disease in each case about equally serious, and in each the same essentials of treatment will have to be regarded.

In our opinion, therefore, a lengthy classification serves no useful end, and we think matters will be simplified by considering quittor under two headings only—­namely, ‘Simple or Cutaneous’ and ‘Sub-horny,’ and discussing the other varieties as simply complications of either of these two.

1.  SIMPLE OR CUTANEOUS QUITTOR.

Definition.—­This condition is simply a sloughing of a portion of the skin of the coronet, together with a portion of the immediately underlying soft structures.