<prompt> According to Denis classification, the middle column includes all of the following, except:Posterior longitudinal ligamentPosterior elements of the spinePosterior pa of the veebral discPosterior pa of the veebral body  <response>: Denis classificationof the structural elements of the spine: Anterior column Middle component Posterior complex Anterior pa of of the veebra and disc Anterior longitudinal ligament Posterior pa of the veebra and disc Posterior longitudinal ligament Posterior elements- pedicles, lamina, spinous processes, facet joints, and the remaining ligaments Association for the Study of Internal Fixation ASIF system reves back to the original two-column theory: Anterior column consisting of veebral body and disc Posterior column consisting of pedicles, laminae, facets and posterior ligamentous complex. 