Inner Knee Pain in seated meditative posture

I’ve been practicing for many years but about 6 months ago developed pain in both inner knees - I feel it mainly in postures involving hip ext rotation - having been able to do padmasana previously, even sukhasana is no longer possible, tree is challenging, janu sirsasan etc. At first virasana, balasana also were not possible but a gentle pulsing back and forth in lunge position released something and I can comfortably do this. Anyone any ideas on what might be causing this inner knee problem? Physios and sports injury therapists so far have been at a loss.

Please provide details like you age ,gender, other medical conditions etc.
Normally if you have been practicing yoga for many years then it should not happen. So something is going wrong somewhere.
Just for an example, I saw similar issue in one of my students but her problem was that she started her dance class despite she was overweight. Dancing damaged her knee ligaments because of her weight.

So knowing about your background is necessary before commenting anything.

Umesh, thanks for your reply. I am in my 40s, female, developed CFS about 4 years ago which means I have not been walking much - though still doing my practice…my saving grace in the midst of this illness. I know that makes the connective tissues weaker than normal - but still search for a therapeutic way to relieve the pain.