Validity and reliability of the WIMU™ inertial device for the assessment of joint angulations

Abstract

Range of motion measurement is fundamental in the physical examination and functional evaluation of different joints. WIMU™ is an inertial device that allows the analysis of joint motion easily in real time. This study had a two-fold goal: (i) to evaluate the validity of WIMU™ on the measurement of different angle positions, compared with a standard goniometer and 2D video-based motion analysis software; and (ii) to evaluate the use of WIMU™ in the assessment of angulations in a joint, specifically assessing the validity and reliability of WIMU™ on the measurement of ankle dorsiflexion, compared to a standard goniometer and Kinovea. The intraclass correlation coefficient and Pearson´s correlation coefficient (r) were performed to calculate the concurrent validity, and Bland-Altman plots were performed to analyze agreement between measures. For the analysis of reliability, both relative and absolute indices were used. The results showed excellent validity and reliability of WIMU™ in the assessment of angle positions and ankle dorsiflexion. The current findings conclude that WIMU™ is a valid and reliable instrument to measure angle and joint motions. In short, WIMU™ provides a new clinical and sportive method of angle measurement.