Iliotibial band syndrome or IT band syndrome is an overuse injury on the outer part of the thigh and knee. It causes pain and tenderness, especially just above the knee joint.
It is often caused by repetitively bending the knee during physical activities, such as running, cycling, swimming, and hiking.
The IT band is a group of fibers that is mainly the length of the upper leg, from the hip to the top of the shin.
When greatly overused, the IT band may be tightened, which can cause the band to rub against the outside of the knee and can lead to pain and swelling.
IT band syndrome may begin as mild pain and will worsen if left untreated. The best treatment for this is to stop doing the activities that are causing the pain to occur, which, in more severe cases, surgical options may be needed.