Originally Posted by
weasel1
Hard to say if a new boot alone would do it. Depends on how your foot acts on the footbed, your position in the boot, how well it follows the shape of your foot and leg, etc. My guess is that the footbed is rigid under the 5th met, and that because of this the 5th met can't drop like it needs to as you go through the beginning-middle of your ankle flexion. So instead, (equal and opposite reaction, remember physics? I barely do) it drives the medial side of the foot inward, twisting the lower leg bones and causing the friction and pressure. That, or the footbed isn't sufficiently supporting the calcaneal shelf, again allowing that to move and twisting the lower leg in the boot. But this is pure conjecture, because I can't see you in it. Positional factors with the shell could be causing it, or just exacerbating it. If the fitters are good, keep at it with them. Sorry I don't have an easy fix for you.
And hey, I'm just a middle-aged desk jockey on the internet these days, so what do I know... ;-)