Iliotibial band syndrome (ITBS) is an overuse injury where repetitive flexion and extension causes inflammation of the iliotibial band when it rubs against the lateral femoral condyle. The iliotibial band is a tendon that runs along the outside of the thigh, from the top of the hip to the outside of the knee. It stabilizes the knee and hip during running, but when it thickens and rubs over the bone, the area can become inflamed or the band itself may become irritated, causing pain. This overuse injury occurs when the iliotibial band, the tendon that runs down the outside of the thigh from the hip to the shin, is tight or inflamed. Inflammation and irritation of the iliotibial band also may occur because of a lack of its flexibility, which can result in an increase in tension on the iliotibial band during the stance phase of running.
Marked by a sharp, burning knee or hip pain, ITBS is a very common running injury among marathoners. Indeed, it’s responsible for as many as 80% of all overuse pains on marathon day.
Symptoms of iliotibial band syndrome:
- Pain may be experienced in the outside part of the hip, thigh or knee.
- Often individuals with this condition will notice more pain with running and going up stairs or hills.
- Occasionally, the pain may radiate along the course of the iliotibial band all the way up to the outer side of the thigh to the hip.
- Pain that generally disappears as the band is stretched out and becomes more flexible.
- Pain that improves with rest.
- Some patients may feel a snapping or popping sound at the knee, and there may be some swelling either where the band crosses the femoral epicondyle or below the knee where it attaches to the tibia.