Kneecap pain after partial knee replacemtn

I had a partial knee replacement on the outside part of my right knee about 5 years ago.  It was very successful - initially with little pain.  However, for the last two years I have had a lot of pain under the kneecap - accompanied by noise sounding like cloth ripping.  My doctor told me it was scar tissue and there was nothing to do for it until I needed the joint replaced with total knee replacement.

I think I can live with the pain in my right knee.  However, I just had (February 2009) a partial knee replacement done on the left (inside part), and I am worried about having the same thing happen.  I practice Aikido - a martial art - which is very vigorous.  I am able to practice again now, very fully.  I have been doing this for 25 years, so it's not something I can give up.  

What do you suggest?

Thank you,

Inga

[Abhijeet Ghosh]

Dear Inga,
You a  very brave person as you are practicing martial arts also along with the Unilateral Knee replacement.
The problem is that with a active lifestyle of your, the implant life will decrease a lot.
And since you don't want to give it up also, so the best way is "Wait and  Watch".
Operation would only be advised, once the pain increases.
Regarding the stiffness due to the scar tissue,would suggest you to continue the stretching exercises of the knee so that the muscles and scar tissue don't get further contracted.This will reduce the pain and help up in the future surgery.
Feel free to discuss more, if things are still unclear .
Regards