Iliotibial band (ITB) is a thickened band of tissue that runs along the outer side of thigh from the pelvis to the shinbone (just below the knee joint). It helps to transmit forces from the hip to the knee and acts a stabiliser of the outer side of knee, playing an important role in postural control.
With bending and straightening of the knee this band moves over the lower outer end of thigh bone and sometimes repeated motion can cause the ITB to irritate the surrounding tissues. This is addressed as iliotibial band syndrome (ITBS) or IT syndrome. It manifests as pain along the outer side of knee after repetitive motion. Although anyone can develop this condition, it occurs more frequently in athletes and those participating in activities involving frequent knee bending and straightening.
Common presenting features include:
ITBS is uncommon in the inactive population. It is seen more frequently in
The exact cause of iliotibial band syndrome is not clear and there may be multiple factors contributing to its development. Most popular belief is that this is an overuse injury resulting from friction from the movement of the iliotibial band over the lower outer edge of the thigh bone, as during repeated bending and straightening of the leg. Most contact between the ITB and lower end of thigh bone occurs when the knee is bent (flexed) at 30 degrees, which is the angle at which the foot strikes the ground and hence the maximal pain at this time. Other theories attribute the condition to the abnormal compression of the tissues beneath ITB or to the inflammation in the small fluid-filled sac (bursa) bone and tendons in the area.
A combination of issues may contribute to its development including
ITBS occurs more commonly in association with certain other conditions such as outer hip pain (greater trochanteric pain syndrome/ trochanteric bursitis) and pain along the kneecap (patellofemoral syndrome).
Iliotibial band syndrome can be diagnosed on the basis of history and examination findings. There is often history of recent change in level of activities with the typical symptoms as explained previously. Tenderness on the outer side of knee just above the joint and other special clinical tests can help in the diagnosis. Investigations such as the MRI or ultrasound scans can help confirm the diagnosis and rule out other conditions with similar presentation.
Ultrasound scan has the advantage of being a rapid, low cost, widely available, in clinic investigation which can demonstrate swelling, fluid collection, bursitis and thickening of the ITB. It has the advantage of being able to compare with the other side and carrying out a dynamic assessment (assessment with leg movement). MRI may show thickening, tearing of ITB or swelling above / below the ITB.
Optimal management of these patients requires a multidisciplinary team approach with the pain specialists and physiotherapists playing the key role.
During this phase the aim is to relieve pain and limit the inflammatory response. This requires activity limitation or modification and refraining from provoking activities such as running. General principles of management during this phase are
Local injections are considered in severe cases where physical therapy and oral medications fail to provide adequate relief. Local injection can help in confirming the diagnosis, providing prolonged pain relief and facilitating early return to routine physical activities, especially when used early in the disease. Ultrasound guidance throughout the procedure is valuable in improving accuracy and reducing complications. Any fluid collection, if present, can be removed at the same time. Post injection activities can be increased in a graded fashion once the patient has been pain free for two weeks.
Once inflammation is under control exercises focussing on stretching and improving flexibility can be started. This lays the foundation for subsequent strength training. Any contributory factors such as footwear, posture, sports specific technique training etc should be addressed.
Most patients are able to return to activity within 6 to 8 weeks. ITBS however can have a fluctuating course and may relapse during the treatment or return to activity phase. Stretching of the iliotibial band, gluteus muscles and strengthening of the low back, hips, knees, and leg muscles is frequently recommended as part of the treatment plan to prevent reoccurrences. Improving strength around the hip helps to reduce the forces on the IT band.
Identifying and addressing the underlying causes of the problem is important. It may involve analysis of gait, leg length, pelvic tilt, and that of muscle strength, balance and flexibility.
Surgical intervention is reserved for refractory cases not responding to the above-mentioned measures for more than 6 months. Options include ITB release, ITB lengthening, removal of bursa (ITB bursectomy), and arthroscopic ITB debridement.