How to describe a listhesis (spondylolisthesis) seen on X-ray as anterior or posterior?

To describe a lithesis (vertebral slippage) as anterior or posterior on an X-ray, focus on the direction of displacement relative to the vertebra below it. An anterior lithesis (anterolisthesis) occurs when the upper vertebra slips forward relative to the vertebra beneath it, while a posterior lithesis (retrolisthesis) occurs when the upper vertebra slips backward. On a lateral X-ray view, identify the posterior vertebral body lines—if the upper vertebra's line is positioned anterior to the lower vertebra's line, it's an anterolisthesis; if positioned posterior, it's a retrolisthesis. The severity is typically graded using the Meyerding classification (grades I-IV), based on the percentage of slippage relative to the width of the vertebral body below. When reporting findings, specify the direction (anterior or posterior), the vertebral level involved (e.g., L4-L5), and the grade of slippage. This directional classification is important for treatment planning as different types of lithesis may require different approaches to management, from conservative therapy to surgical intervention depending on severity and associated symptoms.