ITB syndrome, or runners knee otherwise known as lateral knee pain in runners, is a friction injury where the iliotibial band on the outside of the knee rubs on the lateral epicondyle of the femur. This pain is often felt in runners who compete in distances of greater than 5km and is usually felt when training in a longer, slower training run, compared to feeling better in sprint sessions. The reason for this is that when you are running more slowly, there is more chance for lateral movement in your hips. A good example of this is if you watch someone in a fun run who is running a lot slower than everyone else, you may notice that their hips look like they're sitting back a bit and wiggling from side to side. If you compare that to a 100m sprinter whose arms and knees are pumping forward and back, much more than side to side, the sprinter's hips are going to stay a lot squarer and allow less lateral movement and the hip stabilising muscles are contracting much more strongly.
Lateral knee pain is normally a sign that the lateral stabilisers in the hips are not functionally properly so there is some weakness in the gluteus medius or an imbalance, including too much tightness in the hip flexors or TFL muscles. The ITB is a very strong band that attaches from the iliac crest of the pelvis down to Gerdy's tubercle on the femur and also to the fibular bone. ITB is often described as tight. In patients with lateral knee pain when running, it is normal that the ITB is becoming tight as the hip on the same side is allowed to dip out sideways through the running phase, while the weight is on that leg. This causes tension in the band and increases the friction over the lateral epicondyle of the femur, which over time becomes very sore so the pain is both on the lateral epicondyle and on the surface of the ITB that is rubbing it. both become quite inflamed.
The Soft Tissue Therapy solution to this is to loosen the muscles that are causing imbalance through the hip flexors, glute medius, possibly glute maximus, and definitely the ITB msucles, as well as the quadricep muscles that are tight. Soft Tissue Therapists will sometimes use myofascial dry needling through the quadriceps and TFL and K-tape to support this area and give take home exercises to help strengthen the glute med and create balance between the glute meds on both sides. Interestingly, at the elite level, if athletes present with lateral knee pain on long runs, the main primary treatment, apart from soft tissue work, is doing sprint type sessions, for example: 200m sprints repeated 20 times with walking as rest in between for 60-90 secs. This will prevent the hip stabiliser muscles form getting tired to the point where lateral movement is felt at the hips and can often mean that athletes can run pain free and keep training and fitness up while the pathology settles down.