I'm suffering with patella tendinitis at the moment too, really depressing as I can't run at all currently. Physio has given me various squat exercises and stretches etc I need to do, as well as supplements to take, but no improvement yet.
Make sure to check your runnings style as well, if you haven't. Heel striking did me a lot of damage, and doing Muay Thai and all the associated skipping work that put me onto a front footed style altered my running style for the better. That said, I don't run anymore cuz I hate it.
Yeah, that was the first thing I did when the pain started, fairly certain my running style is okay - although I do overpronate so have trainers with additional support, but can't say I have noticed a difference.
I'm suffering with patella tendinitis at the moment too, really depressing as I can't run at all currently. Physio has given me various squat exercises and stretches etc I need to do, as well as supplements to take, but no improvement yet.