Do Ober Tests Reflect Iliotibial Band Stiffness? A Preliminary Shear Wave Elastography Study

Area of Science:

• Biomechanics
• Musculoskeletal imaging
• Clinical assessment

Background:

• Iliotibial band (ITB) stiffness is commonly assessed using Ober and modified Ober tests.
• The in vivo accuracy of these tests for evaluating ITB stiffness remains uncertain.
• Alternative clinical tests may offer better insights into ITB stiffness.

Purpose of the Study:

• To investigate the in vivo validity of traditional and alternative clinical tests for assessing iliotibial band (ITB) stiffness.
• To determine which clinical tests best correlate with objective measures of ITB stiffness.

Main Methods:

• Cross-sectional study involving 35 healthy males.
• Clinical tests included traditional Ober, modified Ober, and hip extension with tibial external rotation tests, with defined positive cutoff values.
• Shear wave elastography measured the stiffness of the ITB and surrounding muscles (rectus femoris, tensor fascia lata, gluteus medius, gluteus minimus).
• Multivariable logistic regression analyzed associations between clinical test findings and tissue stiffness.

Main Results:

• Higher ITB stiffness was significantly associated with positive findings in the modified Ober test with the hip in extension (OR=1.03, P=.04) and the hip extension test with tibial external rotation (OR=1.04, P=.03).
• The traditional Ober and modified Ober tests showed no significant association with ITB stiffness.
• Shear wave elastography provided objective in vivo stiffness measurements.

Conclusions:

• Traditional Ober-based tests appear to have limited utility for evaluating iliotibial band (ITB) stiffness in vivo.
• Modified testing positions, specifically the modified Ober test with hip extension and the hip extension test with tibial external rotation, may offer more reliable assessments of ITB stiffness.
• These findings suggest a need to reconsider standard clinical assessment protocols for ITB stiffness.