Knee Pain for no reason

I have an individual that has insidious onset of tibial tuberosity tenderness (not patellar tenderness at all). Unable to kneel on the spot. Pain with knee flexion. Looks and smells like OSD but I would not think that it will be there at age 20. He also has no history of OSD through out his adolescence. No redness like with a cyst. Has been suffering for 3 weeks. He has rested for 3 weeks (no running but other activites). No improvement.Any ideas?Please go through prone hip extension, Janda Hip Extension, Janda Side Lying, and palpation through rectus femoris.In this case, my first thought would be to use IASTM through the anterior quad and retest. Other aggressive manual therapy would work as well.Also is there a difference in pain when when he squats with angled tibia vs a vertical tibia?What I believe is happening or can happen is that the lower-crossed's tone of the rectus femoris is so powerful that during bouts of knee flexion, it crushes the patella and/or changes the angle of the patella tendon. It can change every movement into something severely quad-dominant and doesn't yield until there is anterior knee pain like this. Try beating up the rectus femoris, quads, and popliteus and half kneeling hip extension stretch.