Inter-Observer Reproducibility of the “Lumbar Facet Hypersignal Classification” and the Classification of Pfirrmann

Abstract

Objective: To evaluate the inter-observer relationship of the "lumbar facet hypersignal classification" and the correlation with disc degeneration. Methods: Retrospective study of magnetic resonance images obtained from 24 (N=24) patients (9 males and 15 females), aged 35 to 79 years, mean age 48 years and 1 month. The images were reviewed by two spine surgeons, by five orthopedists in training in the specialty of spine surgery and one radiologist to evaluate and quantify the presence of hypersignal lumbar facet and the Pfirrmann Classification for disc degeneration. Results: One hundred and twenty lumbar discs and their joint facets were evaluated by the eight examiners, with data analyzed by the Cronbach test and the Spearman Correlation Analysis with statistically high results, confirming good inter-observer relation for the "Lumbar Facet Hypersignal Classification" and for the classification of Pfirrmann. There was no statistically significant relationship between facet arthrosis and disc degeneration. Conclusions: The results confirm that there is good inter-observer relationship for the classification of Facet Hypersignal and for the Classification of Pfirrmann. However, in spite of a positive relationship, a correlation between facet arthrosis and disc degeneration was not statistically significant. Level of Evidence III; Retrospective Comparative Study.

Grading Systems of Lumbar Facet Joint Inflammatory Changes on Magnetic Resonance Imaging

“…Similarly, Lehman et al 18 developed a system that could be applied to fat-suppressed T2-weighted, or contrast-enhanced, T1-weighted images. Lastly, Longmuir and Conley19 and Rodriguez et al 21 used axial and sagittal T2-weighted to develop their system.…”

“…Czervionke and Fenton,10 Longmuir and Conley,19 and Rodriguez et al 21 used quantitative criteria for their grading systems. The former 2 defined the signal intensity noted within the joint space as the inflammatory marker 19,21.…”

“…They identified the signal abnormality as hyperintensity confined to the FJ capsule or periarticular signal abnormality noted on fat-saturated T2-weighted imaging and used the length of the perimeter of the joint covered by the periarticular signal as the grading parameter 10. All 3 studies used the percentage of the area covered by the FJ signal along the perimeter of the joint cartilage 10,19,21…”

“…After eliminating those that met exclusion criteria, 21 studies were left that described degenerative changes of the FJs, including morphologic and inflammatory changes, using MRI. [9][10][11][12][13][18][19][20][21][23][24][25][30][31][32][33][34][35][36][37][38][39] Six of these 21 studies described a grading system of lumbar FJ inflammatory changes that included edema or synovitis as parameters. 10,11,[18][19][20][21] We focused our detailed analysis on these 6 studies.…”

“…[9][10][11][12][13][18][19][20][21][23][24][25][30][31][32][33][34][35][36][37][38][39] Six of these 21 studies described a grading system of lumbar FJ inflammatory changes that included edema or synovitis as parameters. 10,11,[18][19][20][21] We focused our detailed analysis on these 6 studies.…”