@popolopo No, it’s a different test entirely. I had an MRI and a CAT scan and the hardware looked okay, no problems showed up, although the stem looked close to the “cortex” on my regular x Ray, which I think in this case means the bone. The next test recommended for me was this Triple Phase Bone Scan which is used to definitively rule out any loosening of the implant, to detect any infection, ( doubtful in my case) and see more of what’s going on with the stem. You get an injection of a tiny amount of a radioactive isotope and then a gamma camera looks at it. All very hi tech and hard to understand for a layman like me. I hope your MRI sheds some light on your pain and what to do about it.