I'm sorry to hear about your situation Queenie. You are taking a lot of cortisone already in the form of Prednisone, and that may be causing the side effects. Four joint replacement, wow. Well I've had my knees done. Next up is my left shoulder. I'll put that off until it affects my daily life. So far it's manageable with a cortisone shot every 4 months, 6 months if I'm "lucky".

All the best to you. Joe

For years, I’ve suffered varying degrees of back pain. I did/do countless rounds of PT, which always help a bit. I had several injections back there and generally they help a lot.
About 10 years ago, after not being able to stand for long & walking was near impossible from my feet going DEAD after a few minutes. No relief from what used to work.
I knew I needed to try surgery, having put it off for nearly 20 years since it was first suggested.
I shopped surgeons, until an OR Nurse friend of mine advised me with her recommendation. The bone from lamectomy (?sp) was mixed with cadaver bone to create my L 3-4-5 fusion.
After healing & into PT, it was the best thing I ever did!
The back started to act up a few years ago, as my surgeon told me, from wear & tear above and below the fusion.
A bad injection at a pain clinic and COVID inactivity made pain & mobility difficult.
Today, with good injections and PT, I feel my strength and balance are improving.
Bottom line : surgery wasn’t the cure all for life, but it’s one of the best decisions I ever made.