Howdy, I'm here once again :)
Just before last Xmas I wrecked my thigh muscle badly. The frontmost muscle that is supposed to attach to kneecap teared off the kneecap. Happened while walking on a slippery downward walkway. The doctors eventually sent me to MRI scan, and then it was clear what was wrong. Until then they had been making guesses and wasting time... Knee surgery took place seven weeks ago, and since then I'm recovering on schedule. Just fine. :)