Disc degeneration and chronic low back pain: an association which becomes nonsignificant when endplate changes and disc contour are taken into account.

INTRODUCTION: The objective of this study was to assess the association between severe disc degeneration (DD) and low back pain (LBP). METHODS: A case-control study was conducted with 304 subjects, aged 35-50, recruited in routine clinical practice across six hospitals; 240 cases (chronic LBP patients with a median pain duration of 46 months) and 64 controls (asymptomatic subjects without any lifetime history of significant LBP). The following variables were assessed once, using previously validated methods: gender, age, body mass index (BMI), lifetime smoking exposure, degree of physical activity, severity of LBP, disability, and findings on magnetic resonance (MRI) (disc degeneration, Modic changes (MC), disc protrusion/hernia, annular tears, spinal stenosis, and spondylolisthesis). Radiologists who interpreted MRI were blinded to the subjects' characteristics. A multivariate logistic regression model assessed the association between severe DD and chronic LBP, adjusting for gender, age, BMI, physical activity, MC, disc protrusion/hernia, and spinal stenosis. RESULTS: Severe DD at ≥1 level was found in 46.9 % of the controls and 65.8 % of the cases. Crude odds ratio (95 % CI), for suffering chronic LBP when having severe DD, was 2.06 (1.05; 4.06). After adjusting for "MC" and "disc protrusion/hernia," it was 1.81 (0.81; 4.05). CONCLUSIONS: The association between severe DD and LBP ceases to be significant when adjusted for MC and disc protrusion/hernia. These results do not support that DD as a major cause of chronic LBP.

Modic changes and associated features in Southern European chronic low back pain patients.

BACKGROUND CONTEXT: Conflicting reports exist regarding the prevalence of Modic changes among low back pain (LBP) patients and factors associated with their existence. PURPOSE: To assess the prevalence of Modic changes and other findings on lumbar magnetic resonance imaging (MRI) among Spanish adult chronic LBP patients and the patient characteristics and radiological findings associated with Modic changes. STUDY DESIGN: A cross-sectional imaging study among chronic LBP patients. PATIENT SAMPLE: Four hundred eighty-seven patients (263 women and 224 men) undergoing lumbar spine MRI examination for chronic LBP. OUTCOME MEASURES: Gender, age, body mass index (BMI), lifetime smoking exposure, degree of physical activity, and image features (disc degeneration, type and extension of Modic changes, disc contour, annular tears, spinal stenosis, and spondylolisthesis). METHODS: Ten radiologists from six hospitals across six cities in Spain consecutively recruited adult patients in whom lumbar MRI had been prescribed for LBP lasting ≥3 months. Patients' characteristics and imaging findings were assessed through previously validated instruments. A multivariate logistic regression model was developed to assess the features associated with Modic changes. RESULTS: Modic changes were found in 81% of the patients. The most common was Type II (51.3%), affecting only the end plate. Variables associated with Type I changes were disc contour abnormalities, spondylolisthesis, and disc degeneration. The same variables were associated with a higher risk of Type II or any type of Modic changes, as well as being male, and having a higher BMI. CONCLUSIONS: Modic changes are found in 81% (95% confidence interval, 77-85) of adult Spanish patients in whom an MRI is prescribed for chronic LBP. Modic changes are more likely to be found in males with a high BMI, who also show disc contour abnormalities, spondylolisthesis, or disc degeneration.

Lumbar spine: agreement in the interpretation of 1.5-T MR images by using the Nordic Modic Consensus Group classification form.

PURPOSE: To evaluate intra- and interobserver agreement for the interpretation of lumbar 1.5-T magnetic resonance (MR) images in a community setting. MATERIALS AND METHODS: The study design was approved by the Institutional Review Board of the Ramón y Cajal Hospital. According to Spanish law, for this type of study, no informed consent was necessary. Five radiologists from three hospitals twice interpreted lumbar MR examination results in 53 patients with low back pain, with at least a 14-day interval between assessments. Radiologists were unaware of the clinical and demographic characteristics of the patients and of their colleagues' assessments. At the second assessment, they were unaware of the results of the first assessment. Reports on Modic changes, osteophytes, Schmorl nodes, diffuse defects, disk degeneration, annular tears (high-signal-intensity zones), disk contour, spondylolisthesis, and spinal stenosis were collected by using the Spanish version of the Nordic Modic Consensus Group classification. The kappa statistic was used to assess intra- and interobserver agreement for findings with a prevalence of 10% or greater and 90% or lower. kappa was categorized as almost perfect (0.81-1.00), substantial (0.61-0.80), moderate (0.41-0.60), fair (0.21-0.40), slight (0.00-0.20), or poor (<0.00). RESULTS: Endplate erosions and spondylolisthesis were observed in less than 10% of images. Intraobserver reliability was almost perfect for spinal stenosis; substantial for Modic changes, Schmorl nodes, disk degeneration, annular tears, and disk contour; and moderate for osteophytes. Interobserver reliability was moderate for Modic changes, Schmorl nodes, disk degeneration, annular tears, and disk contour; fair for osteophytes; and poor for spinal stenosis. CONCLUSION: In conditions close to those of clinical practice, there was only moderate interobserver agreement in the reporting of findings at 1.5-T lumbar MR imaging. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.09090706/-/DC1.