Posted: 30/07/2016 at 18:11
All my everyday shoes wear down on the outside edge of the heel. Nearly everyone who heel strikes(walking or running) will land on the outside edge of the heel so the fact that that wears out first isn't really a good indicator of anything. It's what happens after your foot hits the ground that can be significant.
Shin splints could be down to unsuitable shoes or a variety of other biomechanical or muscular imbalances. Given that you mention back pain, it may be that whatever is causing that is affecting the your gait and hence your shins.