@jbuscher123
A couple of things
Even if your MRI shows nothing, you could very well have even Gleason nine prostate cancer. If you were to look through the last year or two of messages in this board, you would find people that had exactly that happened to them. The MRI can be very useful. It is not the final answer.
A biopsy may still be necessary If your PSA continues to rise.

As far as lower back pain goes. I’ve had it for probably 40 years. Hits maybe once a year. I put on this belt. I found about 40 years ago that just stops it. I’ve had it no more or less while I’ve had prostate cancer for the last 16 years. I’ve been on ADT for eight years and it makes no difference to my back pain.

There are muscular issues that can occur from ADT and low testosterone. That could be what’s happening or could just be a normal condition you have. Usually, you hear about joint pain when people have problems with ADT not lower back pain.