this is something basic I haven't resolved in several years.
How much do your backpacks press against your lower back and where?
I'm asking because there seem to be slightly different ways of wearing my backpacks.. I can use the shorter torso length ones or just by wearing the hip belt higher to get the backpack's bottom well above my tail bone.
In another config, the backpack presses against my lower back, just above my tail bone. This config has less weight on my shoulders but once I doubled over from a sharp shooting pain during a hike -- I think it caught a nerve in some bad way.
Anyone else with such experience? Any suggestions about how / where the backpack should and should not press on your back or shoulders would be welcome, even if it is a personal thing for you.