The IT band
Iliotibial tract · tractus iliotibialis
A thick strap of connective tissue down the outside of your thigh.
What it does
The iliotibial tract is a tough band of fibrous tissue running from the hip to just below the knee on the outside of the thigh. Parts of the gluteus maximus and a small hip muscle pull on it, so it helps stabilise both the hip and the knee when you stand on one leg.
Surprising fact
The IT band is so stiff that it barely stretches at all, which is why foam rolling feels intense but doesn't really lengthen it.
Why it matters
Runners who build up distance quickly often get pain on the outside of the knee where the band crosses the end of the femur, called IT band syndrome.
Nearby
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Sources
Drafted with AI help; awaiting a human fact-check against these sources.
Open in the 3D atlas · Suggest a correction · Not medical advice.
3D models: Z-Anatomy & BodyParts3D (CC BY-SA 4.0 / 2.1 JP). Card text CC BY 4.0.