Measuring medial longitudinal arch deformation during gait. A reliability study.

Clinical evaluation of medial longitudinal arch deformation (MLAD) during walking gait is often estimated from static measures of e.g. navicular drop (ND) measured during quiet standing. The aim of the present study was to test the reliability of a new three-dimensional method of measuring the MLAD during gait and to compare this method with a static measure and a 2D dynamic method. Fifty-two feet (26 healthy male participants) were tested twice 4-9 days apart in a biomechanical gait analysis laboratory using a 3D three-marker foot model, a 2D video-based model for the measurement of MLAD during gait, and ND for measurements of MLAD during quiet standing. The 3D method showed the highest test-retest reliability among the measurements of MLAD. Furthermore, the ND showed only moderate correlation with both measurements of MLAD during gait. The new 3D method was found to be highly reliable and showed that ND obtained during quiet standing could not predict the MLAD during gait. The 3D method, or alternatively the 2D method, may be used in clinical settings as reliable methods for easy estimation of the foot longitudinal stability. Copyright Â