Welcome @macadoo. I moved your question about long-term prednisone possibly causing muscle spasms or twitching to this existing discussion:
- The good and bad of Prednisone for PMR https://connect.mayoclinic.org/discussion/prednisone-good-and-bad/

I did this so you can connect with other members like @beryl @edithmiller @marilyncarkner @johnbishop and more.

You may also be interested in this related discussion:
- Prednisone Side Effects https://connect.mayoclinic.org/discussion/prednisone-side-effects-1/

Several members have talked about muscles aches as a side effect of prednisone. Do you have aching along with the spasms?