Is Injections a Cause of Frozen Shoulder Contraction?

Injections work best in the painful stage, they don't seem to work in the stiff phase. So i wonder if one of the reasons why injections work is that it is reducing fibremy fibre blast populations. It could be having an effect on inflammation, which we still don't really understand. But at a physiological level, which i am really interested in, is it possible that if it is a true frozen shoulder, and there are my fibre blass causing the contraction? And this medicine can reduce the number of fibre blast is it restoring homeostasis in the region? Why that, i don't know, but this is, you know, I'm sure to be shot down by