Question: I had a bone scan today I was injected at 9 am,and waited for three hours for the resolution isotope to be absorbed in to my bone marrow.I have had 5 joint replacements,the last one in 2010.It was a revision on my left knee do to the prosthetic joint being encapsulated with heteratopic bone growth.causing severe pain.Last Friday I noticed that my lft knee again was causing loud popping and severe pain and diminished range of motion ,I called my orthopedic surgeon and he ordered plain radio-graphs to determine the cause,the tibial component had a significant amount of HO causing it to become unstable and causing it to piston,the medial portion also was overgrown with heteratopic bone.pryor to the last revision I had radiation to help retard the unwanted bone growth but it was not successful and now I am facing a second revision the first revision was done in Nashville and Dr. XXXXXXX XXXXXXX chose a chrome and cobalt Depuy prosthesis, removing the XXXXXXX and Nephew that had been installed in 2007,several hours into the surgery he called my wife and asked her if I had any metal allergies,having worked as a tool and die maker I was aware that I was allergic to cobalt,and would have a rash when ever I came into contact with the heavy metal,the scan also revealed a number of hot spots including my lft hip also a Depuy and my right shoulder having been replaced in 2004.with a striker.I am curious is there any potential involvement caused by the para thyroid gland responsible for the metabolism of calcium vit.D and Phosphorus or it strictly an idiopathic condition.With the copious amounts of Vit D now being prescribed.as well as phosphorus in diet drinks.I am otherwise very healthy.I am a 54 year old Caucasian with no apparent traumaI am an avid weight lifter and swam competitively for 12 years and played college football and wrestled I also have a number of DVT's and have been on chronic coumadin having developed the clots after my revision in2010 I would greatly appreciate any,ideas as to what could potentially cause this and any suggestions for non surgical options.