Human static postures analysis using empirical mode decomposition

The goal of this paper is to analyze the human stability during static postures using stabilometric signals. The effects of subject's visual input, feet position, age and gender are analyzed. Twenty eight healthy subjects have participated in this study. The center of pressure displacements were measured along the Medio-Lateral (ML) and Antero-Posterior (AP) directions. Empirical mode decomposition method is used to decompose the stabilometric signal into several elementary signals called Intrinsic Mode Functions (IMF). A stabilogram-diffusion method is used to generate the related diffusion curve of each IMF and a resulting index called Critical Point (CP) is calculated. The CP parameter showed significant differences between groups using repeated measure ANOVA, particularly in the ML direction in terms of visual modality, feet position, age and gender. The present findings may guide the rehabilitation process. Our proposed method compares favorably to conventional stabilometric analysis based on the center of pressure excursion calculation.