Sounds "ITB". Important to get the diagnosis right before treating it so see a sportsphysio with an open mind:). The knee is a complex bit of kit as joints go.
I knackered mine playing rugby years ago :eek: and the advice above is sound. I now religiously stretch the lateral aspects of my thighs thoroughly before and after running and have never had another problem (until I don't stretch, then it hurts). The "ITB" is the tendonous fascial sheaf over lying the lateral quads muscle running from pelvic bone to knee.The "ITB" plays an important part in patella tracking and in most people it is a bit too tight leading to pain and further problems with the knee. Therefore, let it heal - ice and exercise within pain boundaries. Stretches - largely as explained above. The best thing to do is have someone show you (I'll be at Tankys on Sunday). I do a standing cross legged hand on hip teapot looking thing.:cool:
I'm sure there'll be a physio along any minute to advise more.

