The knee separates and connects the two longest bones in the body. Because most of the body’s weight bears down on these bones, it is vital to keep the knee happy. I often tell clients that the knee doesn’t have a brain; it is told where to be and what to do by messages coming down from the hip and up from the foot. Many structures help stabilize this inherently unstable stacking of bones, including the focus of this post, the iliotibial band.Iliotibial Band Anatomy 101
Everyone knows that the iliotibial band runs down the lateral thigh and stabilizes the knee by preventing unwanted adduction. This band is a thickening of the fascia lata that envelops the whole of the thigh, like a stocking. The ITB could be considered the tendon of two muscles; the tensor fascia lata (TFL) in the front, and the gluteus maximus at the rear. These act as the upper tensioning and positioning ‘brains’ of the knee. The lower ITB attachments are complex. Some fibers split to attach to the lateral femoral condyle (Kaplan’s fibers) and may merge into the patella, some can attach to the head of the fibula, but most attach to the tibia (Gerdy’s tubercle). Underneath this distal portion is a richly innervated and vascularized layer of fat and connective tissue, instead of the traditional bursa. In ITB friction syndrome (ITBFS), found in runners and cyclists, the lateral femoral condyle is where the point tenderness occurs.
ITBFS Etiology 1 – Top-Down
Andry Vleeming, editor of the classic text ‘Movement, Stability and Lumbopelvic Pain‘, likens the body’s action of shifting the weight onto one leg when walking or running to ‘pole dancing’. As your weight transfers laterally you press the contents of your thigh against the rigid ‘pole’ of the ITB. Runners often develop weak hip abductors that allow the opposite hip to drop (not rise) when in the stance phase. This varus-like (bowing) effect creates extra compressive and shear forces on structures pushing into the distal ITB attachments leading to tissue damage, swelling, inflammation and pain.
ITBFS Etiology 2 – Bottom-Up
Poor rear foot mechanics leading to hyper-pronation can give rise to excessive internal rotation of the tibia. This mal-position means that the distal ITB attachment ends up with more medial rotation, once again leading to more compression and shear forces as the structures underneath push into it. Running on cambers or circular tracks doesn’t help either. Bear in mind you can have both top-down and bottom-up going on.
You Can’t Stretch A Pole
The IT band cannot be stretched. As a ‘pole’ it is what it is. Foam rolling it most likely influences vastus lateralis, the powerful quadriceps muscle that lies under it, front and back (this muscle also pushes out against the iliotibial pole when bearing weight). Before a more invasive procedure is contemplated friction syndrome should be addressed by improving the top-down and bottom-up biomechanics. This includes reducing the trigger points and stretching the two proximal muscles, strengthening the hip’s lateral rotators and abductors, and correction of aberrant foot mechanics.