Changes

Anterolisthesis is classified by degree of the slippage, as measured as percentage of the width of the vertebral body:<ref>{{cite web|url=http://www.massgeneral.org/ortho-childrens/conditions-treatments/spondylolysis.aspx|title=Spondylolysis and Spondylolisthesis of the Lumbar Spine|website=[[Massachusetts General Hospital]]|accessdate=2016-12-14}}</ref>