ABSTRACT
A new impact system for the human spine was introduced (Pope et al., 1987) (see Figure 13.1). The apparatus consists of a platform suspended by soft springs and guided by two linear bearings. The vertical resonance of the system was less than 2 Hz. The frame resonance was 60 Hz, and the platform rotational resonance was approximately 20 Hz. Rotation was minimised if the subject stood or sat in the centre of the platform. The impact was applied by a pendulum to the centre of the platform.
