New Perspectives on ITB Friction Syndrome

By Whitney Lowe, LMT
May 29, 2009

New Perspectives on ITB Friction Syndrome

By Whitney Lowe, LMT
May 29, 2009

If you've ever been running or hiking downhill and experienced a nagging pain on the side of your knee, there is a good chance you were feeling iliotibial band (ITB) friction syndrome. It is an overuse condition resulting from repetitive flexion and extension of the knee in activities such as running, and is considered the primary cause of lateral knee pain.1 Several factors contribute to the problem, including structural deviations in the hip or knee, tightness of the hip muscles, or lack of proper conditioning. However, a new anatomical study sheds a different light on the ITB and requires us to take another view of this problem. It appears the cause of pain and mechanics of ITB function, however, may be different than we have previously thought.

Traditional anatomical illustrations of the ITB (Figure 1) show the ITB as an isolated structure running down the lateral side of the thigh. Viewing the ITB as an isolated structure has led us to perceive it as being capable of moving back and forth in an anterior to posterior direction. While you can grasp the edges of the ITB and feel it move a little back and forth, there may be much less movement occurring in the band than we originally thought.

The lateral epicondyle of the femur is located just underneath the distal fibers of the iliotibial band (Figure 2). Descriptions of ITB friction syndrome in the orthopedic literature state that when the knee is in extension, the band lies anterior to the lateral epicondyle of the femur. They go on to say that at approximately 30 degrees of flexion, the ITB begins to move across the lateral epicondyle and the posterior fibers of the ITB are the first to contact the bony prominence.2 Thickening of the posterior fibers of the ITB, has been observed in some people.3 It is suggested that the apparent thickening of the posterior aspect of the ITB is somehow related to excess friction. It is not clear whether this thickening of the posterior band of fibers is a cause of the excess friction or the result of it.

The perception of the ITB as an independent structure on the lateral thigh is not actually accurate, however. There is a fascial sleeve that encases the entire thigh called the fasciae latae (Figure 3). The ITB is actually a thickened portion of the fasciae latae. Therefore, if the ITB were moving back and forth across the lateral epicondyle of the femur, the entire fasciae latae would have to be moving significantly with it as well and that does not appear to be happening.

A recent study by Fairclough, et al., published in the Journal of Anatomy, has prompted us to take a much different look at the anatomy of the iliotibial band and what happens during ITB friction syndrome.4 This new perspective has significant ramifications for soft-tissue treatment approaches. In addition to highlighting that the ITB is an integral part of the fasciae latae, Fairclough and colleagues also found that the ITB is fibrously anchored to the femur. With the ITB fibrously anchored to the femur, significant movement back and forth across the femoral condyles is unlikely.

A Closer Look

So if the ITB is fibrously anchored to the femur and does not move back and forth across the lateral edpicondyle of the femur, what is causing the pain in this "friction syndrome"? A closer look at knee mechanics reveals what may be occurring. When the knee is flexed, there is a simultaneous internal rotation of the tibia. Conversely, as the knee is extended there is an external rotation of the tibia. The iliotibial band is attached to the proximal tibia at a location called the Gerdy's tubercle. The internal rotation of the tibia during knee flexion pulls the iliotibial band taut. As the tibial rotation pulls the ITB taut, the band presses harder against the lateral epicondyle of the femur. During portions of the flexion and extension of the knee there are different levels of tension on the anterior and posterior fibers of the band. The authors suggest these differences in the tension of the anterior to posterior fibers throughout the flexion/extension cycle are what give the illusion of the band moving over the epicondyle.

There is a layer of fatty tissue just underneath the iliotibial band where it courses over the lateral epicondyle of the femur. When the ITB is under greater stretch and tension as the knee flexes, it is pressing against this richly innervated fatty tissue. According to Fairclough, et al., it is pressure against this fatty tissue, instead of friction against the epicondyle, that causes the pain of ITB friction syndrome.

This new understanding of anatomical and biomechanical factors with the ITB has important ramifications for how we use massage to address this disorder. Previously, friction treatment was recommended directly to the distal ITB to treat this condition. The assumption was that deep transverse friction was one of the best ways to work with fibrous adhesions and tearing of ITB fibers that resulted from rubbing on the epicondyle. With this new understanding of anatomical relationships in the area, our treatment approach will be modified.

According to this new theory, the primary cause of pain in the ITB friction syndrome is the ITB being pulled taut (but not rubbing back and forth) against the lateral epicondyle of the femur and the underlying fatty tissue. Putting additional pressure on this region as we might during friction treatments is therefore not the best strategy. Our approach to treatment should emphasize techniques that help decrease overall tension on the ITB. Tension on the ITB is generated primarily from the tensor fasciae latae and gluteus maximus muscles, which insert into the band. Therefore when we are treating this condition, reducing tension in these muscles and addressing other lower extremity biomechanical compensations are the primary goals for effective resolution.

References

  1. Barber FA, Sutker AN. Iliotibial band syndrome. Sports Med, 1992;14(2):144-8.
  2. Martens M. Iliotibial band friction syndrome. In: Torg JS, Shephard RJ, eds. Current Therapy in Sports Medicine. St. Louis: Mosby, 1995:322-4.
  3. Ekman EF, Pope T, Martin DF, Curl WW. Magnetic resonance imaging of iliotibial band syndrome. Am J Sports Med, 1994;22(6):851-4.
  4. Fairclough J, Hayashi K, Toumi H, et al. The functional anatomy of the iliotibial band during flexion and extension of the knee: implications for understanding iliotibial band syndrome. J Anat, March 2006;208(3):309-16.