Pfirrmann grading describes lumbar disc degeneration on T2-weighted MRI. The original system has five grades based on structure, signal, distinction between disc regions and disc height. It standardises an imaging description and does not directly measure pain or disability.
Meaning on imaging
This classification provides a common language for describing disc appearance. Grade I represents a relatively homogeneous, bright appearance, while grade V includes marked disc-space collapse. Between these extremes, the criteria describe changes in signal, structure and height. The score refers to the disc, rather than the person as a whole.
Indications and assessment
A radiologist or researcher assigns a grade using appropriate T2-weighted images. Different discs in the same person may receive different grades. The original system was studied for agreement between readers, helping researchers compare findings and describe examinations consistently. Agreement is useful, but does not remove all variation between observers.
Limitations and interpretation
The grade is neither a measure of herniation size nor a percentage of disability. Disc changes may coexist with few symptoms. Reading differences and acquisition protocols can affect comparisons. Clinical decisions require the history, examination and other relevant findings, rather than treating a higher number as an automatic reason for intervention.
Role of TAGMED care
At TAGMED, grading can help explain a report but does not determine session numbers or a device-based treatment indication. No grade supports a promise of regeneration through decompression. Goals should remain functional, with discussion of realistic benefits and limitations, and appropriate medical review when the overall findings require it.
Frequently asked questions
Are there five grades or eight?
The original system has five; some modified versions use a different scale.
Does a high grade require surgery?
No. A surgical indication requires specialist assessment of the clinical situation.
Can function improve without the grade changing?
Yes. Pain and physical abilities can improve without a visible change in grading.
Does the grade date the changes?
No. It describes appearance at the examination and does not provide an exact timeline.
What matters when comparing reports?
Check the classification version, the same disc level and sufficiently comparable imaging conditions.
Original conceptual diagram; no patient diagnostic image.
Medical references
- Pfirrmann et al., Spine, 2001. Magnetic resonance classification of lumbar intervertebral disc degeneration.
- Carragee et al., Spine, 2000. 2000 Volvo Award winner in clinical studies: Lumbar high-intensity zone and discography in subjects without low back problems.
- RadiologyInfo.org — ACR, RSNA et ASRT. Spine MRI.
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