Your observation is a good one since the ITB has insertions on the lateral side of the knee, so it is only natural to conclude that the pain was soft tissue related. On the other hand, a careful history would have illustrated that your pain was likely worse with heel strike. Stress fractures usually occur as a result of impact loading. So if you thought about it for a bit, you would have figured out that the fibula was involved. As for the relationship between the two injuries, It is possible that your biomechanics predispose you to both, although no diorect relationhip exists between the two injuries. Although you might have ITB syndrome, that would be a coincidence more related to your biomechanics..
After recovering from a left muscle sprain in three months ago, I started running again and was just about at my training level when I began to experience lateral knee pain two months ago that came on suddenly during a run one afternoon. I continued to run on my knee and the pain worsened. The pain was localized to the lateral part of my knee, produced no swelling, and seemed to subside with rest. The pain usually did not appear until minutes into my run. I took a few weeks off, started to run again, and the pain seemed worse than before and lingered after my run producing so much pain that it was hard to walk. Turns out that I had a fibula fracture, even though I thought it was ITBS. Is it possible that I could have ITBS as well? Does ITBS show up on an MRI? Is a fibula fracture a sequelae of ITBS? How can I improve my recovery?