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A multi-axial test device was designed to obtain the material properties of the lumbar spine in combined loading modes. The custom designed tester consists of a rigid platen driven by three DC powered geared motors. Two motors, each connected to parallel linear actuators control the angular displacement (for flexion and extension) and vertical motion (for tension and compression), while a third DC motor connected to a threaded rod was employed to control the horizontal displacement (for anterior and posterior shear) of the rigid platen. The testing machine is driven in displacement-control mode by a feedback system based on data from three rotary potentiometers. Six entire lumbar spine segments (T12-S1) were potted in aluminum cups with DynaCast and tested within failure limits to compression, tension, anterior shear, posterior shear, flexion, extension, anterior shear-flexion, posterior shear-extension and finally in combined anterior shear-flexion loading.