I had issues with my back too. Switched to sumo. Its basically saved my lifting career so to speak. I can deadlift without any back troubles and I am actually much stronger from that position.
As with anything, let your back heal up and start slowly, let your body adapt to the position, it can beat your hips up if you're not used to it. Also experiment with foot position, foot angle, grip width.
The other thing that really helped my back and subsequently the deadlift was zercher lifts from the rack.
In terms of going back to conv, I have no plans to do so, however I'm sure I could if i wanted without any back issues.