Iliotibial Band Friction Syndromeby John Howick
A common type of knee pain is Iliotibial Band (ITB) Friction Syndrome. This condition is seen in runners and hikers and is usually aggravated with going down hills or stairs. The pain is very sharp and felt on the outside aspect of the knee. The pain commonly starts in the middle of the activity and i is intense enough to make you stop. You usually can't "run through" this pain and are often forced to walk with your leg held completely straight. After the pain settles down there may be a mild ache in the knee and occasionally swelling and/or crepitus (crunching, grinding) is noticed. If the athlete returns to their activity the pain can reoccur, often at the same time as it initially came on (e.g. after running 20 minutes).
What is the cause of all this pain and friction?
The iliotibial band is a thickening of the fascia (thin ligament-like tissue which surrounds and connects all of our muscles) which runs down the outside of the thigh from the pelvis to the upper shin. The ITB helps to stabilize the outside of the knee and hip. Two main muscles attach into the ITB. The Tensor Fascia Latae (TFL) attaches from the front of the hip and the Gluteus Maximus attaches from the buttocks. These muscles work together with the Gluteus Medius to keep our pelvis level when we walk and run. If the pelvis is allowed to drop sideways, the ITB is pulled tight and begins to rub on the outside of the knee. This can cause pain and inflammation. The ITB crosses over a bump on the lower thighbone (femur) at 30° of knee bending. This is the point where maximum pain is felt and it explains why walking with a straight leg relieves the pain.
Why does it seem to come on at the same time in the run or hike?
After you have been exercising for a certain length of time your hip stabilizing muscles may begin to tire out. This allows your pelvis to drop to the side and your knees turn in. This tightens the ITB and as the friction builds up to a critical level, the pain suddenly comes on. Your calf and quadriceps muscles are also beginning to tighten up. This can contribute to the twisting of the knee and tightening of the ITB.
Why is it worse with going down hills or stairs?
When we go down hills or stairs our knees tend to bend and roll in more to try to absorb shock. This causes the ITB to be pulled forwards and rub more as it crosses the bump on the outside of the femur. If our hip muscles are weak and tired out they can't keep our knees turned out in proper alignment.
Is there any other cause of ITB problems?
If the joints at the back of the pelvis (sacroiliac or SI joints) are stiff or in an odd position it can cause the ITB to tighten. The muscles attaching into the ITB can become weak and tight secondary to nerve irritation at the low back. Running or walking on a slanted surface such as a cambered road or side-hill tilt the pelvis and tighten the ITB. Having one leg shorter than the other sometimes leads to ITB problems. Overpronation (flattening) of the foot can cause the knee to roll in and may contribute to ITB pain.
How do I get rid of it and keep it away?
Rest and ice can help with the acute symptoms. You then need to correct the muscle imbalance at your hip. This will require strengthening of certain muscles and stretching others. If your pelvis is not moving properly a physiotherapist can use "manual therapy" to mobilize and align your sacroiliac joints. Proper running shoes and insoles can help correct over pronation. When you are ready to return to running it is best to avoid downhills until your hip muscles have the strength and endurance to control your pelvic movement. A physiotherapist will guide you through an individualized program to get you back into running or hiking. Iliotibial band problems often go away quickly but if you do not correct the muscle imbalances, they can come back just as fast. Keep up with your strength and stretching program and you can avoid "rubbing" your knees the wrong way.