YG - I don't know anything about degenerative lumbar discs and cortisone injections ... sounds hideous especially in your profession ... but I do know about back pain.
Have you ever considered doing a course in the Alexander Technique? I had all sorts of back problems since the age of 12, and particularly exacerbated by all 3 pregnancies and deliveries.
When ds2 was 6 weeks old I started an AT course, and have never looked back. I don't actively 'do' it as much as I should, but I am continuously more aware of my posture, and automatically alert when I'm causing stress to my body.
I'm not saying it would help the pain caused by the injury/damage you already have, but it might help prevent future difficulties.
Anyway, I thought it was worth mentioning anyway.