In this study, we assessed spasticity objectively and quantitatively using the pendulum foot drop test. Twenty-eight patients with spasticity and ten healthy subjects participated in the study. A newly designed table for the motion analysis system using infrared cameras and a foot release mechanism were used. Electromyograph (EMG) was recorded from eight muscles of the lower limb during a foot drop maneuver. The study investigators suggest ‘modified relaxation index’ as a good representative parameter for describing spasticity. This parameter is based on quantitative measurement rather than investigator discretion, as in the modified Ashworth scale (MAS).