Iliotibial band syndrome (ITBS) is an overuse or repetitive motion injury resulting in lateral knee pain at the femoral epicondyle.
The etiology of ITBS involves repetitive knee flexion and extension, resulting in inflammation at the lateral knee between the ITB and the lateral femoral epicondyle. Compression of the ITB at the femoral epicondyle is greatest at 20-30 degrees of knee flexion, termed the impingement zone. Biomechanical and frictional factors are thought to play a role.
Epidemiology including risk factors and primary prevention
ITBS is the primary cause of lateral knee pain in runners. In cyclists, it is the source for 15% of overuse injuries.1 It is more common in women, with a reported incidence in female runners of 16%.2 ITBS can be prevented through proper mechanics during activity, particularly avoiding valgus at the knee. Therefore, proper strength and control of the lower limb are important for prevention, as are extrinsic factors such as footwear and bike fit.
The iliotibial band originates from the fibers of the tensor fascia lata, gluteus maximus, and gluteus medius. Distally, the ITB inserts onto the lateral femoral epicondyle and Gerdy’s tubercle primarily. As such, the ITB is a fascial structure that promotes anterolateral stability of the hip and knee in stance and resistance of large varus torques at the knee.1
Pain from ITBS is commonly thought to be due to inflammation at the lateral femoral epicondyle. A long-held theory of the source of inflammation is related to anterior-posterior friction of the ITB over the femoral epicondyle during flexion and extension of the knee. This is referred to as ITB friction syndrome.3 Anterior posterior motion of the ITB over the lateral femoral epicondyle was shown in a 2013 ultrasound study by Jelsing, supporting this theory.4 An alternative concept initiated by Fairclough involves compression, by the ITB, of a highly vascular fat pad just deep to the ITB, creating inflammation and pain.5
The concept of the knee internally rotating during flexion has implications for the biomechanics of ITBS. Consequently, ITBS has been associated with biomechanical abnormalities in the coronal plane, particularly at the hip, which controls orientation of the lower limb during stance. In a study of female runners, ITBS has been associated with greater peak hip adduction, and with greater peak knee internal rotation angle. Foot and ankle mechanics have not yet been shown to contribute to ITBS.2,6
Disease progression including natural history, disease phases or stages, disease trajectory (clinical features and presentation over time)
Pain associated with ITBS tends to be worse with loaded flexion and extension of the knee, and improves with rest. Early on, athletic activities are primarily affected. However, left untreated, ITBS may also affect activities of daily living.
Specific secondary or associated conditions and complications
The biomechanical factors associated with ITBS are noted to be similar to those associated with patellofemoral pain syndrome. Particularly in runners, these disorders may be seen concurrently. In addition, uncorrected mechanics may predispose athletes to other injuries up and down the kinetic chain.
Of note also are proximal ITB issues, also referred to as an external snapping hip. This involves snapping of the posterior border of the ITB at the level of the greater trochanter of the hip. This can be evaluated dynamically by ultrasound and most often is treated conservatively.7
2. ESSENTIALS OF ASSESSMENT
Patients with ITBS describe lateral knee pain associated with repetitive loading in a weight-bearing position. There may be pain more proximally in the lateral thigh and hip area also. A thorough history should assess for acute or traumatic onset of ITB pain versus insidious onset. The patient’s history may elicit recent change in training habits such as load, cadence, hills, addition of cross-training, resistance training, or changes in footwear. The patient should be asked about other concurrent or recent musculoskeletal injuries and for any neurologic symptoms.
In ITBS, there is tenderness at the lateral epicondyle of the femur, and frequently tenderness along the ITB and at the greater trochanter of the hip. Manual muscle testing of the gluteus maximus and gluteus medius should be performed, as well as testing of hip external rotation. There should be no lateral joint line tenderness at the knee, and no sign of intra-articular disorders.
Tests for ITBS include the Noble compression test (tenderness over the femoral epicondyle with the knee at 30 degrees of flexion), and the Ober test and modified Thomas test for ITB tightness. A full discussion of usefulness of these tests, as well as proper performance, can be found elsewhere.8 A recent study has suggested that the flexibility measured from the Ober test comes from structures other than the ITB.9 Regardless, hip adduction flexibility is felt to be important in the biomechanics of ITB syndrome.
The examiner should look for muscle substitutions compensating for weakness in the gluteus medius or gluteus maximus. This includes reliance on other hip musculature, including TFL, hip flexors, and/or hamstrings. Common functional tests are the step-down test and the single-leg squat. Signs of gluteal weakness include internal rotation of the weight-bearing femur, hip adduction, and contralateral hip drop.1
Labs are not commonly included in the assessment of chronic exertional ITBS. Acute pain with any suspicion of infection can be investigated with labs such as CBC, ESR, and CRP.
Magnetic resonance imaging (MRI) may be used to evaluate for thickening of the ITB over the lateral femoral epicondyle. Ultrasound can evaluate ITB anatomy as well, and has added advantages of ability to perform a dynamic exam, and ability to assess for hypervascularity of the fat pad deep to the ITB.
Ultrasound studies find fluid at the ITB to be pervasive in both symptomatic and asymptomatic individuals. Such fluid should therefore be interpreted with caution as a sign of ITBS. This fluid likely emanates from the knee joint, representing a synovial fold of the lateral synovial recess.12,13
Supplemental assessment tools
Sport-specific functional tasks may be evaluated. Video gait or cycling analysis may be useful in athletes to detect biomechanical abnormalities during athletic performance. Footwear and bike fit should be assessed.
Early predictions of outcomes
Severity and duration of symptoms at presentation may predict the course of recovery. More severe symptoms predicting a longer course may include pain at rest or with activities of daily living.
Training errors, including rapid changes in mileage, pace, speed work, or hills contribute to overuse injuries (including ITBS), as rapid increases do not allow adaptation to increased levels of stress. Running shoes should be fitted to an individual’s foot type and should be replaced at regular intervals. Bike fit can be adjusted to decrease time in the impingement zone.
Social role and social support system
Social support during recovery for an athlete includes the physician, physical therapist, athletic trainer, coach, teammates, and family.
Safely returning an athlete to practice and competition requires excellent communication between the patient, treating providers (physician, physical therapist, athletic trainer), and coaching staff. Returning an athlete to play too soon may result in re-injury, and ultimately more time away from competitive sport.
3. REHABILITATION MANAGEMENT AND TREATMENTS
Available or current treatment guidelines
While there are no standardized treatment guidelines for treatment of ITBS, most patients improve with non-surgical care focused on treating inflammation and addressing contributing biomechanical factors. A table of recommendations for phases of rehabilitation were published by Fredericson and Wolf and is summarized below from that article.12
Goal: Reduce inflammation of the iliotibial band at the lateral femoral epicondyle.
- Control extrinsic factors, such as rest from running and cycling.
- In severe cases, patients should avoid any activities with repetitive knee flexion-extension and swim using only their arms and a pool buoy.
- The use of concurrent therapies is advised (i.e., ice, phonophoresis, or iontophoresis).
- Corticosteroid injection, if no response to the above methods.
- Up to 2 pain-free weeks before return to running or cycling in a graded progression.
Goal: Achieve flexibility in the iliotibial band as a foundation to strength training without pain.
- Iliotibial band stretching
- Soft tissue mobilization to reduce myofascial adhesions
Recovery strengthening phase
Goal: Strengthen the gluteus medius muscle, including multiplanar closed chain exercises.
- Exercises should be pain free.
- Repetitions and sets of exercises are 8-15 repetitions and 2-3 sets.
- Recommend the exercises of sidelying hip abduction, single leg activities, pelvic drops, and multiplanar lunges.
At different disease stages
For the acute phase, steroid injections in ITBS have been studied. A 2004 trial of steroid vs. placebo injection in runners with ITBS revealed a significant difference in pain with running in the first two weeks after injection.13 Flexibility is important in the subacute phase. Efficacy of ITB stretches were studied by Fredericson. The most effective stretch was performed with the ipsilateral leg extended and adducted behind the other leg. The subject raises the arms overhead and then laterally bends toward the contralateral side.14
The goal of strengthening is improved neuromuscular control. For the recovery strengthening phase, certain strength patterns have been associated with abnormal hip mechanics in ITBS. Hip flexion and internal rotation is increased in individuals with a tight and strong TFL, along with a relatively weak gluteus maximus and gluteus medius. This may result in a Trendelenburg sign and subsequent poor control of the lower limb during stance, increasing stress at the ITB.1 Fredericson confirmed hip abductor strength deficits in patients with ITBS. He also showed resolution of symptoms in 90% of individuals after a six-week strengthening program focusing on the gluteus medius. Improved control of hip adduction and knee varus was noted as well.15
An article by Baker includes specific exercise recommendations based on electromyography (EMG) studies for recruitment of appropriate gluteal muscles. The exercises include an ITB stretch, resisted gluteal strengthening, and functional closed chain exercises.1 A variety of similar exercises to improve motor control of the lower limb are also included in a recent chapter by Baker and Fredericson. These include pelvic drops, step downs, single leg squats, and others. Strengthening of the posterior gluteus medius and of the gluteus maximus are emphasized.16
Mechanics can also be addressed in cyclists, where bike fit is important, avoiding toeing-in and the 30-degree flexion impingement zone.
In refractory cases of ITBS, surgery can be effective. An arthroscopic technique has been shown to have good outcome, and offers opportunity to treat intra-articular pathology of the knee concurrently.17 At least six months of conservative care is recommended prior to surgery.
Coordination of care
Treatment of an athlete with ITBS must involve communication between any affected individuals, including the patient, physical therapist, trainer, and coach.
Patient & family education
As ITBS is an overuse injury, the patient must be educated on training-related issues. These may include mileage, hills, footwear, cycling equipment, and others specific to the affected individual. Gait coaching may be appropriate.
A successful outcome in ITBS is pain-free return to play. Athletes treated for ITBS may resume sports when they can perform exercises in proper form without pain. They should also exhibit pain-free range of motion (ROM), full strength, normal Noble testing, and have no ITB tenderness. Exercise should be resumed gradually on a flat surface.1
Translation into practice: practice “pearls”/performance improvement in practice (PIPs)/changes in clinical practice behaviors and skills
An understanding of lower limb biomechanics, so the practitioner may treat the root cause of ITBS, rather than localized symptoms, is important for full recovery. Mechanics are influenced by training habits, so a thorough training history is essential. A biomechanical physical exam should be performed, addressing the complete kinetic chain, including the core as well as proximal and distal control of the lower limb.
4. CUTTING EDGE/EMERGING AND UNIQUE CONCEPTS AND PRACTICE
Cutting edge concepts and practice
The newest anatomical information in ITBS involves the universal presence of fluid at the ITB, not from an inflamed bursa, but from the knee joint itself.10,11
As the evidence base grows for regenerative injection therapies, there may be utility in treatment of ITBS.
5. GAPS IN THE EVIDENCE-BASED KNOWLEDGE
Gaps in the evidence-based knowledge
Although physical exam is the gold standard for diagnosis, there are no standards for interpretation of MRI or ultrasound imaging in ITBS.
In addition, more research is needed in the subset of patients who have biomechanical abnormalities distal to the knee contributing to ITBS.
- Baker RL, Souza RB, Fredericson M. Iliotibial band syndrome: soft tissue and biomechanical factors in evaluation and treatment. PM&R. 2011;3(6):550-561.
- Noehren B, Davis I, Hamill J. ASB clinical biomechanics award winner 2006: Prospective study of the biomechanical factors associated with iliotibial band syndrome. Clin Biomech (Bristol, Avon). 2007;22(9):951-956.
- Orchard JW, Fricker PA, Abud, AT, Mason BR. Biomechanics of iliotibial band friction syndrome in runners. Am J Sports Med. 1996;24:375-379.
- Jelsing EJ, Finnoff JT, Cheville AL, Levy BA, Smith J. Sonographic evaluation of the iliotibial band at the lateral femoral epicondyle: does the iliotibial band move? J Ultrasound Med. 2013;32(7):1199-206.
- 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. 2006;208(3):309-316.
- Ferber R, Noehren B, Hamill J, Davis IS. Competitive female runners with a history of iliotibial band syndrome demonstrate atypical hip and knee kinematics. J Orthop Sports Phys Ther. 2010;40(2):52-58.
- Choi YS, Lee SM, Song BY, Paik SH, Yoon YK. Dynamic sonography of external snapping hip syndrome. J Ultrasound Med. 2002;21:753-758.
- Malanga GA, Nadler SF. Musculoskeletal Physical Examination: an Evidence-Based Approach. Philadelphia, PA: Elsevier; 2006:253-254.
- Willett GM, Keim SA, Shostrom VK, Lomneth CS. An anatomic investigation of the Ober test. Am J Sports Med. 2016;44(3):696-701.
- Jelsing EJ, Finoff J, Levy B, Smith J. The prevalence of fluid associated with the iliotibial band in asymptomatic recreational runners: an ultrasonographic study. PMR. 2013;5(7):563-7.
- Jelsing EJ, Maida E, Finnoff JT, Smith J. The source of fluid deep to the iliotibial band: documentation of a potential intra-articular source. PMR. 2014;6(2):134-8.
- Fredericson M, Wolf C. Iliotibial band syndrome in runners: innovations in treatment. Sports Med. 2005;35(5):451-459.
- Gunter P, Schwellnus MP. Local corticosteroid injection in iliotibial band friction syndrome in runners: a randomized controlled trial. Br J Sports Med. 2004;38(3):269-272.
- Fredericson M,White JJ, Macmahon JM, et al. Quantitative analysis of the relative effectiveness of 3 iliotibial band stretches. Arch Phys Med Rehabil 2002;3:269-72.
- Fredericson M, Cookingham CL, Chaudhari AM, Dowdell BC, Oestereicher N, Sahrmann SA. Hip abductor weakness in distance runners with iliotibial band syndrome. Clin J Sports Med. 2000;10:169-175.
- Baker RL, Fredericson M. Iliotibial band syndrome in runners: biomechanical implications and exercise inventions. Phys Med Rehabil Clin N Am. 2016;27:53-77.
- Michels F, Jambou S, Allard M, Bousquet V, Colombet P, de Lavigne C. An arthroscopic technique to treat the iliotibial band syndrome. Knee Surg Sports Traumatol Arthrosc. 2009;17(3):233-236.
Original Version of the Topic:
Heather D. Fullerton, MD. Iliotibial band syndrome. Publication Date:2012/12/28.
Heather D. Fullerton, MD
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