pain after 2 total knee replacements

Hi there, just wondering if it is possible to have arthirtis in a knee which has been totally replaced.   I am a 42 year old female with two tkr.  I have had very good luck with both of them with the exception of this winter.  I live in Canada, central Ontartio and we have recently experienced some very cold winter weather and at first my newest replaced knee was very sore (replaced May 2008), now two weeks later my older replaced knee (December 2006) I very, very sore and swollen.  The doctor feels it is pulled muscles from a slip or stiff walking (because I am afraid of falling).  I am on naproxen and take tylenol arthritis as prescribed by my physician but the pain has gotten work particularly in the last few days.  So I guess my question is, can the knee replacements be affected by the cold weather, my stiff walk and could it be arthritis?  I do wear compression stocking during this time but by the end of my work day (I work in a group home) the pain is severe (I take morphine at night for this) and the swelling is unreal.  What are your thoughts on this.  I ice and keep elevated, any other suggestions and do you think the pain will eventually subside.  I was doing fantastic prior to this.  Please let me know.

[Michael L Gross, MD]

It is not likely to be arthritis, in the true sense.  The joint is removed and replaced with metal and plastic, therefore the tissues normally affected by arthritis are gone.
IWhen you say you have been doing well until recently, I interpet that as meaning you are taking no pain meds, are experiencing minimal pain, and there is no swelling or other outward signs of problems.
The recently rplaced knee is less than a year old, and still may have occasional pain if you rehabilitation was incomplete and you are putting in particularly strenuous days.  The older knee is another story. Swelling and pain are never a good sign.  If this is a sudden onset of dysfunction, and you were truly doing well until recently, it can be ominous.
It may be necessary to have x-rays to rule out loosening of the prosthesis.  Following that, if there is a fluid collection in the knee, it might be a good idea to aspirate the fluid and send it for culture to rule out infection. Finally, a WBC labeled bone scan is a useful test to differentiate between mechanical inflammation and infection.
You definitely should see your surgeon as soon as possible,