Dynamic evolution of equivalent von Mises stress in a lumbar spine segment (the patient underwent bilateral Facectomy at the L5-L4 level) during stance phase of a mild running scenario. The applied force corresponds to the vertical force component of the ground reaction force as registered by a force plate. A detailed description of model on which this scenario was preformed, may be found in the Journal of Clinical Biomechanics 28 (9-10) (2013) 949-955.