There is more and more evidence that PMR is synovitis that mostly is in the hips and shoulders. While PMR is associated with GCA which is a vasculitis there doesn't seem to be that much evidence that PMR alone is a vasculitis.

I believe synovitis in the hands might make the diagnosis of PMR less likely but not impossible. Anything pertaining to PMR seems to be possible because it overlaps with many other health conditions. It is difficult to say what causes what.
https://creakyjoints.org/education/what-is-synovitis/
Synovial cysts are well known in rheumatoid arthritis (RA). Someone with RA like @pb50 might know what to suggest.

I have a synovial cyst on my lumbar spine that causes problems for me. Surgery on my lumbar spine is said to be my best option but pain will be the "deciding factor."