Validity and Reliability of the WIMU(TM) Inertial Device for the Assessment of Joint Angulations

Range of motion measurement is fundamental in the physical examination and functional evaluation of different joints. WIMU(TM) 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(TM) 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(TM) in the assessment of angulations in a joint, specifically assessing the validity and reliability of WIMU(TM) 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(TM) in the assessment of angle positions and ankle dorsiflexion. The current findings conclude that WIMU(TM) is a valid and reliable instrument to measure angle and joint motions. In short, WIMU(TM) provides a new clinical and sportive method of angle measurement.