Herniation of cartilaginous endplates in the lumbar spine: MRI findings.

OBJECTIVE

The purpose of this study was to determine reliable MRI findings suggesting disk herniation with cartilage endplate herniation in the lumbar spine.

MATERIALS AND METHODS

The records of 73 patients who underwent lumbar spinal MRI and lumbar microdiskectomy between March 2005 and January 2009 were searched to find those with the diagnosis of disk herniation with cartilage endplate herniation confirmed during surgery. The following morphologic features were assessed: posterior corners (posterior marginal nodes, dorsal corner defects, Modic changes, and posterior osteophytes), mid endplates (endplate irregularities, Modic changes), and heterogeneous low signal intensity of extruded material. The chi-square test and multiple logistic regression analysis with age, body mass index, and sex as covariates were used for the analysis. The ROC curve was obtained with scores of the statistically significant MRI findings.

RESULTS

Posterior marginal nodes, posterior osteophytes, Modic changes in posterior corners, mid endplate irregularities, Modic changes in mid endplates, and heterogeneous low signal intensity of extruded material were significantly more frequent in patients with disk herniation with cartilage endplate herniation (0.000 < p < 0.009). The AUC for diagnosing disk herniation with cartilage endplate herniation with our scoring system of the six MRI findings (0-6) was 0.888.

CONCLUSION

The presence of disk herniation with cartilage endplate herniation could be ascertained with the following MRI findings: posterior marginal nodes, posterior osteophytes, mid endplate irregularities, heterogeneous low signal intensity of extruded material, and Modic changes in posterior corners and mid endplates.