Originally Posted by Kampfer
I've been squatting regularly for more than two years and have had no back pain, and I usually rep 80-90% 1RM; usually three sets of six-eight reps. I would say for you it's a long-term condition.
In the wise words of Mark Rippetoe:
"Yes, if you squat wrong it fucks things up. If you squat correctly, those same fucked-up things will unfuck themselves."
Don't know if OP's form is good - We all know the squat exercise won't harm when done correctly
. So root cause is OP's form, or an underlying issue not related to squatting altogether (posture, etc...).