What iliotibial band syndrome is
The iliotibial band is a broad, very strong strip of connective tissue running down the outer side of the thigh, from the pelvis to the shin bone. At the knee it passes over the lateral epicondyle of the thigh bone. Beneath the band lies a well-innervated layer of fatty tissue. According to the hypothesis that dominates today, repeated knee bending at around 20–30 degrees – that is, at the moment of landing while running – compresses and irritates it.
That is why the pain usually appears after a certain distance and gets worse on downhills, when the knee works in exactly that range. A slow, long run can be worse than a fast one, in which the knee bends more.
In the assessment we look for tenderness over the lateral epicondyle and check whether the pain can be provoked by bending and straightening the knee under load. We assess hip muscle strength, the squat and stepping down from a step on one leg and, where possible, a video of you running. We also rule out a lateral meniscus tear and problems with the lateral collateral ligament or the popliteus tendon, all of which can cause pain in a similar place.
Watch out for the name and for myths
The name “runner’s knee” is used loosely for this problem and also for pain at the front of the knee, around the kneecap – that is a different problem, described on the page about anterior knee pain. We tell the two apart in the assessment, and you will find a general overview of causes on the knee pain page.
It is also worth being honest about what cannot be done. The band cannot be stretched or “massaged out” in the sense of lasting lengthening – it is a structure so stiff that the forces used in foam rolling or massage do not change its length. A foam roller can reduce pain temporarily, and if it helps you loosen up, you can use it. It does not, however, treat the cause.
What really helps
The foundation is modifying your training. For a few weeks we shorten runs to below the pain threshold, drop downhills and running on a sloping roadside, and often suggest a slight increase in cadence – a shorter stride reduces the load on the knee and the hip. We introduce the changes in small steps so as not to overload other areas.
The second pillar is strength. Some runners with this problem have weak hip abductors, and glute training and single-leg exercises help control the alignment of the pelvis and knee better. We run it as medical training with graded load. Manual therapy is an add-on here that makes the first weeks easier, and for some people dry needling of the glutes and thigh is also helpful.
Return to running and when to come in
With a well-managed plan, most runners get back to full mileage within a few weeks. The most common mistake is going straight back to long runs and mountain routes as soon as short runs stop hurting. Downhills are added at the end. The same mistakes in a training plan are often behind shin splints – which is why, during the return, we look at the whole running week, not just the knee.
A simple rule helps: you run for as long as you can without pain, and increase the distance only once several sessions in a row go smoothly. It is worth keeping hip strength exercises twice a week after the return too – especially when preparing for a longer race. If the pain on the outer side of your knee comes back on every longer run, book a visit via the Contact page.