Re: pain in upper leg/thigh
Ive had joint pain for years and years and I have a hunch I know what youre talking about. Theres a pretty complex web of tendons right above your knee that keep your muscles in line and connect to all the bones and joint material around the kneecap.
First thing I would ask would be about your inflammatory response, not only to injury, but other health issues (inflammation can increase due to a bajillion reasons. Mine they think, is autoimmune)
Try a good epsom salt bath and increase your magnesium content- lots of RAW almonds. not roasted. not salted. raw.
and wear good shoes:-)