The iliotibial (IT) band is a long series of tissues that begin with a connective tendon at the hip, passing along the outside of the thigh to connect to the tibia bone of the lower leg at a point below the knee. The major component of the IT band is the tensor fascia lata, a muscle. The IT band is essential to all aspects of effective running motion, forward, backward, and laterally. The most important aspect of the IT band is the prevention of adduction, or inward movement, of the upper leg during running. The IT band also aids in the stability of the quadriceps, as it protects the large thigh muscle, acting as a barrier on the outer aspect of the thigh.
The natural motion of running places significant demands on the IT band. As the band is required to stretch with every stride, the extension of the IT band is coupled with the stresses presented by other irregularities that affect how the legs move during the running motion, such as uneven leg length, which may cause the condition known as over-pronation, in which the foot rolls inward to an excessive degree. Running laps on a track in a single direction, or a workout along a uneven crowned road, may all precipitate further stresses on the IT band. IT band problems may also arise when distance runners enter the preseason phase of their training and they increase their mileage too quickly relative to their training base, or when the runner wears shoes that are overly worn on the outside of the heel.
While running is the primary source of IT band injuries, the sports of weightlifting and cycling can also contribute to this condition.
The friction associated with the overuse or associated injury to the IT band usually is first noted as pain on the lateral or outside edge of the knee. Less frequently, the pain may be noted at the hip where the IT crosses the hip joint. The knee pain does not always occur when the athlete is at rest; pain will often become sufficiently prominent after running approximately 2 mi (3 km). The resultant knee pain may often be most prominent while the athlete is running downhill. In addition to sensations of pain near the knee joint, the affected area is usually tender to the touch and somewhat swollen. IT band friction can persist indefinitely unless treated; treatment may take up to six months to be completely effective, although most cases of IT band friction will resolve themselves within six weeks, if rehabilitation is thorough.
As painful as IT band friction may be for the athlete, it is usually a problem that is capable of being permanently remedied. The solutions are diverse and they must be assessed in the context of the individual circumstances of each athlete. The remedies include can include: reducing both the volume and the intensity of training; running only on smooth, flat surfaces, to minimize the stresses on the IT band; using ice after all workouts; considering the use of anti-inflammatory medications for a brief period (not to exceed 10 days); beginning and maintaining a thorough stretching and flexibility program; employing cross-training methods; using custom-made orthotics; and returning to full workouts should be progressive, with increases of no more than 5% training volume per week to further protect against reinjury.