If you’ve got a nagging pain on the outer part of your knee, especially if you’re a runner, it could be a symptom of iliotibial band (IT band) syndrome. It’s an injury often caused by activities where you bend your knee repeatedly, like running, cycling, hiking, and walking long distances.
Your IT band is a thick bunch of fibers that runs from the outside of your hips to the outside of your thigh and knee down to the top of your shinbone. If your IT band gets too tight, it can lead to swelling and pain around your knee.
IT band syndrome usually gets better with time and treatment. You don’t typically need surgery.