Iliotibial band syndrome is the inflammation (swelling) of the iliotibial tract (also known as the iliotibial band or “IT band”). This long band of flexible fascia extends from the hip to the knee on the outer side of each leg. The IT band thickens at the knee. If the band is tight – for example, because if insufficient stretching before exercise – it can rub excessively against the femur (thighbone) or iliotibial bursa inside the knee. Continued rubbing can cause the IT band to become swollen and painful.
The most common symptom of IT band syndrome (sometimes referred to as “ITBS”) is pain located on the outer side of the knee that increases as a person runs, cycles or performs other exercises with repetitive leg motion. A person may also experience a feeling of clicking, popping, or snapping on the outside of the knee.
IT band syndrome is usually caused by inadequate or improper stretching prior to exercise, but other factors such as a person's individual biomechanics or even wearing worn-out running shoes can make some people more susceptible to this condition. The key treatment for IT band syndrome is to stop the activity causing the inflammation and rest. This should be followed up with a consultation with a health or fitness professional who can help determine the causes of your IT band syndrome, and provide stretching instructions and other tips to help prevent it.
See below for more information, including videos on stretches and performance training you can do to prevent and treat IT band syndrome and other running injuries.