DISEASES FROM FAULTY CONFORMATION 175 
all movement of the crack apparently restricted. There is 
always a tendency, however, for such a dressing to work 
loose, and in the case of a complicated crack it has the 
disadvantage of permanently hiding from view the changes 
taking place in the discharge from the fissure. 
(e) By wedging the Crack.—This is the exact opposite of 
clamping. Whereas in clamping we obtain immobility of 
the crack by keeping it fixed in the position of greatest 
approximation of its edges, in wedging, the crack is rendered 
free from movement by maintaining it in that position 
where its edges are most widely separated. In this case 
the edges of the crack are pared smooth, the cavity 
thoroughly cleansed, and a wedge of hard wood firmly 
driven in so as to fit exactly the fissure. 
On the face of it it appears that this procedure would 
really tend to force open and so lengthen the crack, especi- 
ally at its coronary extremity. What one should really 
remember, however, is that the crack is not made wider 
than before, but that it is simply maintained in a position 
occurring with every contraction ‘of the heels of the foot, 
when it is normally at its widest. \Movement of the edges 
is thereby stopped, the immediately surrounding structures 
are rested, and a new growth of horn, free from crack, 
induced to grow down from the coronet. 
This method of treatment only serves to emphasize the 
fact that, with a sand-crack once formed, it is the constant 
movement of the parts that tends most to keep it in exist- 
ence, and not any particularly marked exertion of force. 
Some practitioners, with the wedge, apply also a clamp, 
thus assuring additional firmness and solidity to that 
portion of the wall under treatment. 
The method of wedging is undoubtedly successful, if 
neatly performed. 
(f) By Surgical Shoeing.—A partial rest is given to the 
affected parts by easing the bearing of the shoe at the point 
required. This may be done either by removal of part of 
the wall at the spot indicated, or by thinning the web of 
the shoe in the same position. 
