A new alternative to the Ober test for evaluating the difference between right and left iliotibial band stiffness: A reliability study

Abstract

Introduction

A dysfunctional stiffness of the iliotibial band can be related to pathologies of the pelvis/lumbar spine and the knee. The classic and modified Ober tests are the gold standard for assessing iliotibial band stiffness. However, to the authors’ knowledge, this test lacks adequate validation, and its specificity is questionable. A more reliable test is needed to better correlate iliotibial band stiffness to pathologies and to support treatment choices.

Method

Two examiners assessed the difference in stiffness (right vs. left limb) of the iliotibial band by direct fingertip palpation in 40 subjects (without clinically evident painful symptoms), before and after a specific 20-h training session. The difference in stiffness was evaluated with both a 3-level and a 7-level graduation. The intra- and inter-examiner (intra-day) reproducibility was calculated, and a validation of the manual assessment was performed with a myotonometric measurement of frequency and stiffness.

Results

The test achieved post-training agreement consistently greater than 0.88 (weighted Cohen's K test) in intra-examiner assessment and 0.72 in inter-examiner assessment. Before training the agreement was less than 0.48 and 0.12, respectively. Manual versus instrumental agreement was fair to moderate (frequency 0.347; stiffness 0.470).

Conclusion

The newly proposed manual test to assess ITB stiffness by direct palpation showed almost perfect intra-examiner reproducibility and good inter-examiner (intra-day) reproducibility. The specific training was fundamental. Comparison of manual vs instrumental stiffness assessment of the iliotibial band, as proposed in this study, is debatable.