I also experienced unusual pain after getting down to 1mg of Prednisone per day. For me it was pain in sternum and rib cage which my primary believes was costochondritis rather than PMR. I also had pain in hips and glutes which wasn’t unusual, but only on one side of my body which was odd. My inflammation numbers were also elevated so was moved back to 5mg/day by my rheumatologist. 30 days later most pain has resolved except for glute pain which has diminished. Hoping to taper down to 4mg at my next appointment.