Earlier this year a knee lost range of motion after a track meet. As I continued to run the pain behind my knee increased and the range of motion became less and less. Xrays, MRI and 3 opinions later, the undisputed diagnosis is my knee cap cartilage is gone. As a masters runner I kept my milage reasonable and wasn't experiencing knee specific pain so it was a surprise. PT and cortisone haven't helped so my last chance to jog (not race is getting a synthetic lubricant shot. Has anyone had any success with this? There are 4 brands out there and I was going to try euflexxa.