Picture of Iliotibial Band (ITB)
The iliotibial band (ITB) is a ligament that runs the entire length of the upper portion of the leg. It connects the outside of the knee to the top of the hip. The ITB provides stability to the hip and knee during running. Sometimes the band thickens and rubs over bone. This irritates the band and may result in pain and inflammation.
Text Reference: American Family Physician, vol 71, 2005: "Iliotibial Band Syndrome: A Common Source of Knee Pain"