Since you haven’t posted in a bit I’ll assume things are going well for you Kefu.  Have had some good results lately with some changes I’ve made to my bike fit and pedal stroke.  I noticed my affected knee was flaring out a bit at the top of my pedal stroke, so I’ve started to concentrate on keeping the knee tracking straight up and down during the rotation.  I also widened my q-factor a bit by moving my bike cleats in, which effectively moves my foot away from the centerline of the bike.  I also added some adduction to my strength routine, considering my knee was flaring out, it seems like adduction might help balance things and smooth out my pedal stroke.  On the seated hip abduction/adduction machine I can easily max out the stack for abduction(~200lbs, 3 sets of 5), but adduction I can only comfortably lift 120lbs(3 sets of 5).  Is there an agreed upon ratio of abductor to adductor strength?