Study design: A new magnetic resonance imaging (MRI) classification of disc degeneration was correlated with discography. It was also studied for intraobserver and interobserver variability in interpreting disc abnormality and for the capability in predicting symptomatic disc.
Objective: To correlate the results of discography with a new MRI classification for disc degeneration and the presence of the vertebral endplate changes and the high intensity zone (HIZ).
Summary of background data: MRI and discography have been compared in numerous studies as methods for detecting disc degeneration. The results were conflicting and the role of MRI in assessing discogenic pain remains ambiguous.
Methods: One hundred thirty-one discs in 55 patients were studied with pain provocation discography and MRI. A new MRI classification was correlated to discography and assessed together with the presence of end plate changes and HIZ, by the sensitivity and specificity in predicting a painful disc.
Results: MRI classification had a good intra and interobserver agreement and a significant correlation with discographic findings. The sensitivity and specificity of MRI in predicting painful disc was 94% and 77%. The sensitivities and specificity of HIZs was 27% and 87% and for end plate changes was 32% and 98%, respectively.
Conclusions: Although MRI is an excellent investigation for assessing disc morphology it should be interpreted along with discography findings before planning fusion surgery. The proposed MRI classification is a useful aid in predicting painful degenerative disc. The utility of HIZs and end plate changes is limited due to low sensitivity.