362 DISEASES OF THE HORSE’S FOOT 
parts. This is done that we may be quite certain nothing 
at all remains calculated to give rise to further trouble. 
It goes without saying that, in addition to the necrosed 
cartilage, all other diseased and necrotic tissues should also 
be removed. The os pedis is occasionally found necrotic 
just where the cartilage joins it, or it may be that a small 
portion of the sensitive laminz, by reason of its lver- 
red or even gray coloration, gives evidence of death of 
the part. 
The former must be well curetted, and the latter cleaned 
carefully with a scalpel and forceps. 
Fic. 142.—ParriaL Excision oF THE LaTERAL CARTILAGE BY 
REMOVING A PORTION OF THE CORONARY CUSHION. 
The dotted lines show the outline of the wedge-shaped portion of 
structures to be removed, including skin, coronary cushion, horn, 
and sensitive lamine. 
u, The opening of the fistula. 
The operation finished, the foot is again douched in an 
antiseptic solution, the wound mopped dry with carbolized 
tow, dressed with either of the dressings described on 
page 858, and finally bandaged. The dressing should be 
changed every three days only, unless in the meanwhile 
pawing movements and other symptoms of distress indicate 
their removal. 
The length of coronary cushion removed in this operation 
is from + to 4 inch (we ourselves, however, have seen it 
more), and yet its loss seems to occasion no serious after- 
