pain after total knee replacement

I am 47 years old and have rheumatoid arthritis, i had total knee replacement done in May of this year, i had a good out come and was released from my doctor and physical therapy 5 weeks after surgery.  In the last two weeks my knee has become increasingly painful and even sore to the touch on the outside of the knee, I have not injured my knee to my knowledge and do use the stairs and walk on a daily basis. I feel as though I am bothering my surgeon to call and ask him as to what can be causing this yet I am almost back to the amount of pain I had before surgery. I have even gone to taking pain pills so I can sleep or sometimes even function on a daily basis. I would like to know if this is common or if there could be some other reason.  Is there anyone else who has had this kind of a problem?

[ruthbest]

I has TKR 12/31/09. I have burning pain. The pain extends eight inches down my leg in all directions. I went to another doctor who, did not perform the surgery for a second medical review. I had knee xrays, which show no problems. The new doctor said it is nerve damage and send me to a pain specialist.  This involves nerve blocks for the pain. I have not taken the injections, which would be in the back I am going today to see if some kind of pills that available. I am just miserable in pain and depressed from my having this much pain daily. The pain is there 24/7 and increased when I stand to walk on it. If you find a solution please advise.