This is a common repetitive stress or overuse injury.  It can be a result of many structural and mechanical imbalances in the hip, pelvis and foot creating excessive loading of the IT band.  This will usually create friction were the tendon passes over the outside of the knee. 

Treatment

It is essential to locate and correct the imbalances that lead to IT band syndrome.  Functional soft tissue therapy (A.R.T., Graston)  is used to break up scar tissue and restore normal function and motion to the tissues.   Functional  rehabilitation is then important to retrain the correct function of the tissues, reducing the risk of future injury, and also enhancing performance.