To determine the limits of spinal displacement before the onset of neurophysiological changes during spinal surgery. Assessing if the type of force applied or the section of the adjacent nerve roots increases the tolerance to displacement. Experimental study in 21 domestic pigs. Three groups were established according to the displacing force applied to the cord: separation (group 1, n=7), root stump pull (group2, n=7) and torque (group3, n=7). Successive records of cord-to-cord motor evoked potential were obtained. The displacing force was removed immediately when neurophysiological changes observed. The experiment was repeated after sectioning the adjacent nerve roots.Objectives
Methods