Clinical Biomechanics of Iliotibial Band Syndrome
Original Editors - Jazmin Brown as part of The University of Waterloo Clinical Biomechanics Project
Clinical Definition[edit | edit source]
The iliotibial band is a fascial band that is located on the lateral side of the leg; originating from the gluteus maximus and tensor fascia latae muscles, and extending past the lateral femoral condyle, where it inserts onto the Gerdy’s tubercle on the tibia. Iliotibial Band Syndrome, also known as ITBS, is generally considered to be an overuse injury, and is typically related to the repetitive knee flexion and extension seen during a running gait. Originally, the knee pain associated with ITBS was thought to be caused by friction from the iliotibial band acting on the femoral lateral condyle as it rubbed anteriorly and posteriorly over the bony prominence, specifically during 30˚ of knee flexion. However, a seminal research article examining the functional anatomy of the iliotibial band through magnetic resonance imaging has provided an updated and more accurate theory on the source of the pain associated with ITBS. The results demonstrated that during knee flexion, the iliotibial band does not actually slide over the femoral condyle and cause friction. Instead, the iliotibial band creates compression forces over the condyle, which translate into the highly innervated fat pad beneath it, stimulating mechanoreceptors that lead to pain perception. Females are twice as likely to develop ITBS than males, which suggests that there are anatomical and physiological differences that play a part in the development of ITBS, and that the biomechanical causal factors between sexes are different.
Running Mechanics[edit | edit source]
ITBS is often referred to as “Runner’s Knee”, because of the high prevalence of this injury in runners, primarily due to the increased amount of repetitive knee flexion and extension they experience within a continuous running gait cycle. Although the level of compression forces acting on the lateral femoral condyle by the iliotibial band in each gait cycle is quite small, a build-up of these forces due to overuse, typically associated with changes to training volume, can eventually surpass the local knee tissue’s adaptive capability, resulting in pain and injury. The running gait cycle requires coordination between multiple joints, segments, muscles and passives structures, such that a change or abnormality in any of these components within the kinetic chain can translate up or down the body and create adaptations or compensations in other segments that may also contribute to injury. It is evident though, that not every runner, cyclist, or individual undergoing repetitive knee flexion will go on to develop ITBS; suggesting that there are biomechanical factors related to the kinetic chain that when magnified by repetition and overuse, may result in compression forces that exceed tissue tolerance and progress into the pain associated with iliotibial band syndrome.
Joint Posture and Positioning[edit | edit source]
Prospective cohort research on the running biomechanics of females, has given rise to a variety of potential joint postures and positions in the gait cycle that contribute to the development of ITBS. During the stance phase of running, individuals presenting with a greater amount of knee internal rotation and peak hip adduction went on to develop ITBS. Both of these alterations in limb and joint postures increase the level of strain on the iliotibial band due to the attachments at both the pelvis and the tibia; crossing both the hip and knee joints. The increased amount of strain within the iliotibial band will cause it to tighten against the lateral femoral condyle; increasing the amount of compression on the accompanying fat pad during the specific impingement zone of 30 degrees of knee flexion, and resulting in pain. The internal rotation present at the knee is theorized to be primarily due to an externally rotated femur instead of an excessively internally rotated tibia. This is indicative that the increase in medial knee rotation in individuals who went on to develop ITBS, is likely a result of proximal factors, specifically muscular imbalances at the hip.
Muscular Imbalances[edit | edit source]
Lack of prospective research, and contradicting retrospective research has made it difficult to determine if the muscular imbalances present within an individual are a cause or consequence of ITBS. Nonetheless, multiple theories have been proposed in order to explain potential reasons for how alterations in the proximal musculature can influence the activity of the iliotibial band and lead to harmful levels of compression at the knee. There are two main groups of muscles that are responsible for the level of rotation at the femur. If there is an imbalance within the musculature that allows for an excessive amount of femoral external rotation, it may translate down the kinetic chain and result in an increased level of knee internal rotation during the stance phase, which has been linked to ITBS development. Weakness within the internal femoral rotators such as the gluteus minimus, gluteus medius, and tensor fascia latae will allow the femur to rotate externally without resistance. Likewise, tension and tightness within the external femoral rotators such as the gemellus superior/inferior, obturator internus/externus, piriformis, and quadratus femoris may hold the femur in an externally rotated position during the gait cycle. The increase in peak hip adduction during the stance phase of running is thought to be attributed to a weakness in muscles responsible for hip abduction; the gluteus minimus, gluteus medius and TFL. If these muscles are not strong enough to prevent the hip from going through hyper-adduction, the iliotibial band will be forced to stretch along the lateral thigh and compress the lateral femoral condyle and respective fat pad. Additionally, the iliotibial band may increase tension to attempt to create a compensatory effect against the stretch to maintain hip alignment, furthering the level of compression at the knee. Tension within the iliotibial band will also increase and cause further compression at the knee when the gluteus maximus and tensor fascia latae eccentrically contract in order to decelerate the lower limb during the impingement zone within a running gait. Together all of these muscular imbalances, magnified by overuse, may indirectly or directly increase the level of compression acting on the lateral knee and stimulate pain.
Neuromuscular Control[edit | edit source]
Strain rate is described as the change in the amount of iliotibial band strain between the initial touchdown and maximum knee flexion within a running gait cycle. Despite no difference in the impingement duration, females who have gone on to develop ITBS did initially present with a higher strain rate within their iliotibial band than their injury-free counterparts, implying that rate of strain may be a contributing causal factor to this injury. Research and discussion around the role of musculature hypothesizes that it is the timing of muscle activation, not the magnitude, that may be responsible for the changes seen in joint kinematics and increases in strain rate, present in individuals who go on to develop ITBS. Specifically, patterns of early hip flexion and early knee flexion during a running gait have been associated with individuals with ITBS. Reduced joint coordination and segmental control may also contribute to ITBS pain by increasing the amount of stress on the related tissue. Individuals more likely to develop ITBS have been shown to present with atypical coupling patterns within the hip and lower limb; specifically lower ranges of hip abduction/adduction coupling. A reduced ability to achieve highly varying movement coupling is thought to limit the amount of possible coordination patterns within the gait cycle and as a result, perform abnormal and repetitive motor patterns that stress the iliotibial band.
Injury Prevention[edit | edit source]
By identifying potential biomechanical causal factors of ITBS that are present in individuals who engage in high volumes of running, changes in training can be made to address and prevent further development of these factors to avoid experiencing the debilitating pain associated with this syndrome. Choice of footwear is crucial in determining the effects of the foot on the proximal aspects of the kinetic chain. Although individuals with a leg length discrepancy may benefit from custom designed footwear to promote symmetry within running mechanics, this is not the case for every runner. Barefoot running has been shown to decrease hip adduction and knee internal rotation in comparison to running shod, and although this may not be attainable during long distance training, it demonstrates that careful thought should be put into determining the most suitable type of footwear for related activities. Feedback provided on running gait mechanics has also been shown to reduce abnormal arthrokinetics within the lower limb that are linked to overuse injuries, such as the larger hip adduction angles seen in those who develop ITBS. Verbal and visual feedback; specifically in the form of mirror gait retraining, are successful in encouraging individuals to consciously pay attention to their gait patterns and adjust accordingly to achieve movement patterns that reduce the level of tissue stress. Cueing individuals to run with adequate space between their knees, while still having them point forwards, along with activation of their gluteal muscles can result in decreased hip adduction and reduce the amount of stress the iliotibial band places on the lateral femoral condyle.
Injury Management[edit | edit source]
- The treatment of ITBS is usually non-operative, and physiotherapy should be considered the first and best line of treatment.
- The best exercises to start will depend on the causative factors obtained from the subjective and objective assessment.
- Myofacial treatment can be effective in reducing the pain experience in acute phase, when pain and inflammation in the insertion is felt.
- The use of a foam roller on the tight muscles could also be beneficial.
- Exercises to strengthen the abductor muscles and stabilise the hip can be helpful if clinically indicated.
- Activity modification should also be addressed.
- Pain management with modalities, medications can be given.
References[edit | edit source]
- 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. Journal of Anatomy. 2006;208(3):309-316.
- Taunton JE. A retrospective case-control analysis of 2002 running injuries. British Journal of Sports Medicine. 2002;36(2):95-101.
- Bertelsen ML, Hulme A, Petersen J, et al. A framework for the etiology of running-related injuries. Scandinavian Journal of Medicine & Science in Sports. 2017;27(11):1170-1180.
- Ceyssens L, Vanelderen R, Barton C, Malliaras P, Dingenen B. Biomechanical Risk Factors Associated with Running-Related Injuries: A Systematic Review. Sports Medicine. 2019;49(7):1095-1115.
- Noehren B, Davis I, Hamill J. ASB Clinical Biomechanics Award Winner 2006. Clinical Biomechanics. 2007;22(9):951-956.
- Louw M, Deary C. The biomechanical variables involved in the aetiology of iliotibial band syndrome in distance runners – A systematic review of the literature. Physical Therapy in Sport. 2014;15(1):64-75.
- Worp MPVD, Horst NVD, Wijer AD, Backx FJG, Maria W. G. Nijhuis-Van Der Sanden. Iliotibial Band Syndrome in Runners. Sports Medicine. 2012;42(11):969-992.
- Hamill J, Miller R, Noehren B, Davis I. A prospective study of iliotibial band strain in runners. Clinical Biomechanics. 2008;23(8):1018-1025.
- Ferber R, Noehren B, Hamill J, Davis I. Competitive Female Runners With a History of Iliotibial Band Syndrome Demonstrate Atypical Hip and Knee Kinematics. Journal of Orthopaedic & Sports Physical Therapy. 2010;40(2):52-58.
- Miller RH, Meardon SA, Derrick TR, Gillette JC. Continuous Relative Phase Variability during an Exhaustive Run in Runners with a History of Iliotibial Band Syndrome. Journal of Applied Biomechanics. 2008;24(3):262-270.
- Kerrigan DC, Franz JR, Keenan GS, Dicharry J, Della Croce U, Wilder RP. The Effect of Running Shoes on Lower Extremity Joint Torques. PM&R. 2009;1(12):1058-1063.
- McCarthy C, Fleming N, Donne B, Blanksby B. Barefoot Running and Hip Kinematics. Medicine & Science in Sports & Exercise. 2015;47(5):1009-1016.
- Letafatkar A, Rabiei P, Farivar N, Alamouti G. Long‐term efficacy of conditioning training program combined with feedback on kinetics and kinematics in male runners. Scandinavian Journal of Medicine & Science in Sports. 2019;30(3): 429–441.
- Willy RW, Scholz JP, Davis IS. Mirror gait retraining for the treatment of patellofemoral pain in female runners. Clinical Biomechanics. 2012;27(10):1045-1051.