Trajectories of the center of pressure (COP) of human body during different stances measured on healthy individuals and patients with spine and joint diseases have been measured. Fourier and continuous wavelet transforms have been used for statistical analysis of the trajectories and 3D representation of the spectral power density (SPD) in both frequency and time domains. The corresponding multilink models have been analyzed and the influence of fixation or pathology of separate joints have been studied. Novel indexes for clinical diagnostics of joint pathologies have been proposed.

Keywords: posturography, postural sway, spectral analysis, biomechanics, clinical diagnostics