My new pain has a name: Humeral Osteonecrosis

I posted here a few weeks ago seeking insights into new shoulder pain that I assumed was just osteoarthritis that I have everywhere. Quick snapshot: 68 yr old male, professional musician, PMR since Oct 2014, currently reducing from 9 mg pred, Tylenol for other pain relief. Went to see orthopedist to check on progress of bilateral knee replacement last July; asked him to check my shoulders which have recently been the source of a lot more than PMR pain, and got the diagnosis of avascular necrosis, both sides, left one worse, I had read about this, and had a friend who had to have a hip replacement because of heavy drinking. Can also be caused by steroid use, Or by who knows what?  Anyway, shoulder replacement seems the only long term outcome, so I guess I'm not finished with that (already have two hips along with the knees noted above). Tylenol and Ibuprofen are doing a nice job with the pain, but the crepitus you can hear is really scary! Waiting for my shoulder surgeon appointment. 

Yuk!!! It IS rare... Can also be caused by the "bone protection" bisphosphonates which they often had out alongside pred. One wonders whether taking both is a good idea...

You'll be totally bionic soon 

Yes, it is a rare side efect of prednisone.  What bad luck.  But it sounds as though there is a suitable treatment.  If you ever fly, what will security make of you!!!