A grade 1 Meyerding classification describes how much anterior translation?

• A. 0-25% anterior translation
• B. 25-50% anterior translation
• C. 50-75% anterior translation
• D. 75-100% anterior translation

Answer: (A)

Meyerding’s grading assesses how far the upper vertebra slides forward over the one below, expressed as a percentage of the width of the lower vertebral body. For the first grade, this forward translation is 0 to 25%, meaning the slip is mild. On imaging, this is seen as a small forward displacement on a lateral view, and as the percentage increases, the slip becomes more pronounced (25–50%, 50–75%, 75–100%, and over 100% for spondyloptosis).