Apical corns occur predominately on toes that are hammered or clawed. If the toe is clawed then pressure is transferred through the apex of the toe rather than underneath the toe.
Note the presence of extravasation (dried blood) under the corn.
Apical toes respond well to wearing a gel toe prop that sits under the toe and thus lifting the end of the toe reducing pressure.
If the corn is treated every 6 to 8 weeks (for a period of a few months,) and a gel toe prop is worn EVERY day, then the majority of apical corns can be prevented from reappearing.