>>839687>>839748I came here a little too late and a lot of cyberdoctoring have already been done and OP might not be still here. BUT, the going about tentonitis is propably right. I'm not into playing doctor online, i'm propably wrong and YOU SHOULD GO SEE A SPORT PHYSICIAN, but I happen to have the same thing in my left knee, in french it's called " syndrôme rotulien" and it translate into "patella syndrome", but I don't know if it's called that way in english.
It's an inflammation of the patella tendon that is painful when the tendon is stretched, aka where the leg is bended. The pain might be just under the patella, and you need to get your leg straight to ease it. It's also called cinema syndrome, from a pain caused by sitting a long time.
It's caused by activities done without proper leg musculation. It's treated with physiotherapy, some orthopedic soles can help. The goal is to better the muscles in the leg so there's a better balance between tension and extension.
I haven't started physio yet, but I've been in pain for 8 months now... To confirm the diagnosis, I did an MRI last month which sowed lesion on the tendon so I had to stop running to avoid making worse. I'm on holiday right now, but when I get home I'll definitely start physio.