My lower back is destroyed! So I wanted to tell you what really helped me. I pretty much just play acoustic, started out that way because of the weight vs. a solid body electric. Anyway after a few months of playing hunched and in pain I tried the strap. Might sound silly but the way my back is I didn't want anything hanging off of my neck lol. I was surprised at how much easier this was not only on my back but to play. You can sit up straight and still see the fretboard without hunching as much. Just a thought. I hope you find a way to play with less pain. Keep at it,

Ed