iliotibial-band-itb-syndrome-pathogenesis-and-clinical-findings

iliotibial-band-itb-syndrome-pathogenesis-and-clinical-findings

Iliotibial Band (ITB) Syndrome: Pathogenesis and clinical findings
Authors: Ciara Hanly, Alyssa Federico Reviewers: Tara Shannon, Hannah Koury, Mehul Gupta
Extrinsic Risk Factors
Intrinsic Risk Factors
Genu varum or valgum (deformity causing outward or inward bowing of knees, respectively
↑ Lengthening of ITB at lateral femoral epicondyle
Ryan Shields*
* MD at time of publication
Leg length discrepancy
Compensatory
unilateral foot pronation and hip drop of shorter leg
↑ Stretch of ITB on longer leg
Sudden ↑ in training volume and overtraining
Repetitive flexion and extension of lower limb (i.e. running, cycling)
Running surface with horizontal or vertical gradient
↑ Knee flexion at foot strike
Excessively long strides
↑ Hip flexion
Hip abductor weakness (gluteus medius, gluteus minimus, tensor fascia latae)
↑ Hip adductionà internal rotation at the knee
Excessive foot pronation
↑ Stretch of ITB
ITB originates from the iliac crest, runs past the lateral femoral epicondyle, and inserts into the lateral aspect of the proximal tibia
Irritation of bursa between ITB and lateral femoral condyle
Lower limb flexion and extension displaces the ITB over the lateral femoral condyle in an anterior-posterior direction
↑ Friction between ITB and lateral femoral condyle
Audible snapping sensation as the band is displaced over bone
Iliotibial bursitis
+ Noble’s compression test:
Patient supine with hip and knee flexed to 90o, pressure is applied to distal ITB while patient extends hip and knee àpain over distal ITB at 30o flexion
Blood vessels, nerves, Pacinian corpuscles (pressure and vibration receptors), and vascularized fat pad are compressed in sub-ITB space
Activation of nociceptors (pain receptors) in femur
Micro-trauma to ITB
Inflammatory response and scar tissue formation
Swelling of ITB
+ Ober test: Patient lays on unaffected side with knee flexed to 90o, hip abducted and extended, and patient asked to adduct hip as far as possibleà unable to adduct farther than the exam table
Tenderness to palpation over lateral femoral epicondyle
Radiating pain in dermatomal distribution to outer thigh and calf
Pain over lateral femoral epicondyle during maximal point of ITB tension, just prior to or during foot strike (i.e. during downhill walking or running)
lateral knee
thickens
Persistent pain throughout exercise
Legend:
Pathophysiology
Mechanism
Sign/Symptom/Lab Finding
Complications
Published May 8, 2022 on www.thecalgaryguide.com