Sorry you are having the back issues. You better question your doctor, you won't rest well until you know what is going on. I know the worry you feel, I am the same way. I had two surgeries on my neck, and I know because of the pain that I have some degenerative changes. I am 61, and this started for me at 54 years old. I had that domino effect where the vertebrate above and below the original surgery site failed.
If you have already had three trips to the OR, you need to try to avoid any more.
Have you gotten another opinion? Have you tried something called Ketamine infusions? This is a procedure that threads the med. through the areas that are having trouble. I had great relief from that for a matter of months. It is done with that scope and a pain specialist. If you can look into that, it may be a better option than steroid injections. I am not a big fan of those. Too many side effects and pain from them.
What exactly did your surgeries do? I didn't see anything in your MRI about former hardware etc. Sure wish I could help you. Seek that other opinion before you do anything OK? Be good to yourself. ginnie