The Meyerding grade classifies how far one vertebra has slipped relative to the vertebra below it. Displacement is expressed as a proportion of the lower vertebral body's anteroposterior diameter, usually on a lateral radiograph. The grade does not directly measure symptoms.
Meaning on imaging
The system usually describes forward slippage. Grade I extends up to 25%; grade II is greater than 25% through 50%; grade III is greater than 50% through 75%; and grade IV exceeds 75% through 100%. Beyond this, the term spondyloptosis is used, often called grade V.
Indications and assessment
Measurement uses an appropriate lateral image, often obtained while standing. Assessment also considers the cause of slippage, leg symptoms, strength and activity limitations. Additional images may examine the nerves or movement at the segment when that information would influence management. The measured percentage is only part of the evaluation.
Limitations and interpretation
The grade describes static displacement and does not independently establish dynamic instability. A small slip can be symptomatic, while another may be well tolerated. Age, progression, spinal balance and possible nerve compression matter when choosing care. The number cannot serve as a treatment prescription without that clinical context.
Role of TAGMED care
At TAGMED, spondylolisthesis requires assessment of precautions before mechanical care. The grade does not automatically justify traction or a promise to move the vertebra back into place. Suspected instability or evolving neurological findings needs appropriate medical review, with urgency determined by the symptoms and examination.
Frequently asked questions
Is the grade a percentage of pain?
No. It quantifies displacement seen on an image.
Does grade I mean there is no risk?
No. Symptoms, stability and other findings still need assessment.
Will a lying-down MRI give the same result?
Not always. Position and weight-bearing can alter the amount of visible slippage.
Does a high grade always require surgery?
A specialist considers the whole situation; the grade alone does not determine the decision.
Can function improve without reducing the slip?
Yes. Clinical outcomes and the radiographic displacement are different aspects of the condition.
Original conceptual diagram; no patient diagnostic image.
Medical references
- Rivollier et al., Journal of Orthopaedics, 2020. Surgical treatment of high-grade spondylolisthesis: Technique and results.
- American Academy of Orthopaedic Surgeons. Adult Spondylolisthesis of the Low Back.
References document the topic; their inclusion does not imply endorsement of TAGMED services by those organizations.
Educational information from The Spine Page. This entry does not replace an individual assessment. Documentary version: October 12, 2026. Sylvain Desforges, B.Sc., D.O., N.D., osteopath and naturopath.
TAGMED clinic contact details
For non-urgent consultations and information about available services.
Clinique TAGMED — Terrebonne
1150, rue Lévis, Suite 200
Terrebonne (Québec) J6W 5S6
450‑704‑4447
Clinique TAGMED — Montréal
1140, avenue Beaumont
Mont-Royal (Québec) H3P 3E5
1‑877‑672‑9060