ITBS is common in runners, cyclists and other athletes. The iliotibial band is a thick, fibrous band of connective tissue that runs all the way from the hip, down the outside of the leg, to the knee. Pain can happen anywhere along this pathway, but often occurs at the outside of the knee.
Jeff Chen, MD, MHS, says that knee pain is likely caused by excessive friction during repetitive knee flexion /extension. With each repetition the lower end of the ITB slides over the outside bone at the knee, causing inflammation, thickening, and swelling.
ITB pain may appear after:
- Running downhill
- Lengthening your running stride
- Sitting for long periods with the knee in a flexed position.
Some risk factors include:
- ITB tightness
- High mileage running
- Leg length discrepancy
- Muscular weakness or imbalance (particularly hip abductor weakness at the buttock)