Hi EFB.
 
So sorry to hear about the complications you have had with your knee replacement. Have you discussed this patella pain with your doctors?
 
I have never had a knee replacement, and cannot give you advice related to personal experience, but I did do some research to see if I could find some information for you. I came across the mention of patella fractures as a potential complication following knee replacements. Has this possibility been discussed with your doctor?
 
Some symptoms/signs of a fracture of the kneecap include:
 
*Pain when moving the knee forward or backward.
*Swelling around the fracture. .
*"Catching" or locking of the knee.
*Tenderness when pressing the kneecap against underlying bones.
 
Here is a link to a study on patellar fractures after KR and how common they may be: http://www.ajronline.org/cgi/reprint/185/3/655.pdf.
 
It says in this study that patella fractures occur following approximately 1.14% of knee replacements. And the average time period between the knee replacement and a patella fracture was 17.5 months (almost a year and a half).
  
I hope this information may help you a bit! Good Luck!