msobo,
I'm glad you're persuing this with a specialist. You signature doesn't list Prednisone...were you ever on it? There is alot of misinformation out there about osteonecrosis (ON) and I believe wholeheartedly that there are more people walking around with this than many people realize. It is often misdiagnosed or looked over for many years because an MRI wasn't done to detect it in the early stages.
I don't know if you've read any of my previous posts, but in a nutshell, here is what happened with my daughter: Colitis spread through her with a fury...from beginning to end, 3 months on Pred and surgery for the jpouch on in a span of 4 months. Digestively she's doing great...a year later her knee became swollen/painful with a grinding popping sound and after x-rays (whic was negative), phys therapy, and a rheumatologist who wisely suggested an MRI "just to rule out anything mechanical" discovered "bone infarcts" on the MRI. These are areas of dead bone. After searching for treatment, we found a specialist who suggested aggressive MRI of all joints. At the time, only her knee and right elbow were bothering her which we thought was an extraintestinal manifestation of the UC-arthritis of some sort. Long story short, like my signature states, it's pretty much throughout her body. Many of the joints aren't symptomatic, so we still wouldn't know she has it if we hadn't done MRI's. But, we've been able to get her joints operated on to hopefully halt the progression of the disease.
I'm not saying you have it, but there are red flags in your story, ie, "..sharp stabbing pain towards the core of my right buttock...worsens throughout the night and mornings are tough...substantial grinding felt and at times even heard."
"i recall having a hip xray about 8mth-1 yr ago by my regular dr because of this ailing hip/buttock pain but the xray's were supposidly negative (this was when i was in real pain). I guess that initailly ruled out arthritis of any kind" .... see, here is one of the things that keep people from getting to the bottom of their pain (especially anyone who's been on Prednisone. X-rays, if it is osteonecrosis, will not show the necrosis until in the later stages, and by then, the bone is breaking down and fracturing leaving the bone disease to go undetected in the body until it's too late for joint preservation techniques. An MRI will rule this out, so I applaud you for seeking an answer.
If at anytime you want any additional information or if you discover that you have ON, you can click on my name and find my email address. I'm happy to share any info or insight that would help someone else. All the best to you!