Knee fragment post Tkr

I had robotic TKR 8 months ago and have had pain doing stairs and getting up and down from a sitting position. Surgeon who performed surgery told me to wait since X-rays looked fine. I finally went for a second opinion and he scheduled me for a bone scan and CT scan. The bone scan showed increase radiotracer uptake in the upper patella and some patellar tendonitis. CT scan noted fragmentation at upper patella sight. Second opinion surgeon had suspected possible loosening of the kneecap. I did not see that verbiage in the report, however.

I had a bad experience with the first surgery and am reluctant to go through any revision surgery that was initially suspected might be necessary
Any suggestions on non-surgical treatments available to alleviate the pain and address this issue? I am 78 years old and am active female who is very distraught since I am unable to enjoy my life these past 8 months. What could have caused this since I did not injure myself and have been extremely diligent about going to PT. Thank you.