A New Manual Alternative to the Ober Test: A Pilot Study of Precision and Accuracy in Healthy Young Adults

The objective of this study was to evaluate the intra-rater and inter-rater reliability of a new clinical test for assessing the hip adductor myofascial system and determine its accuracy by comparison with inertial sensor data. A diagnostic reliability study was conducted involving 46 healthy participants (92 limbs) aged 18-30 years. Each participant underwent a standardized assessment using a newly developed manual test for hip adduction, performed by two trained examiners during two separate sessions (T0 and T1). Inertial sensors were used to measure hip adduction angles as the reference standard. Intra-rater and inter-rater reliability were assessed using intraclass correlation coefficients (ICC). Agreement between visual assessments and instrumented measurements was also analyzed. Post-hoc power calculations were performed for all ICC values. The new test demonstrated good intra-rater reliability, with ICC values of 0.881 for examiner 1 and 0.840 for examiner 2. Inter-rater reliability was also good, with ICC values of 0.888 at T0 and 0.886 at T1. Agreement between visual assessments and inertial sensor measurements was high, with ICC values of 0.898 for examiner 1 and 0.931 for examiner 2. Bland-Altman plots confirmed strong agreement across all comparisons, and power analyses showed sufficient sample size for all ICC calculations. The new test provides a reliable and accurate assessment of hip adductor myofascial extensibility, addressing key limitations of the Ober test. Its good intra- and inter-rater reliability, along with ease of use in clinical settings without instrumentation, make it a promising alternative. Future research should explore its application across diverse populations and its clinical correlation with iliotibial band-related pathologies.