Correlation between MR imaging and discography with provocative concordant pain in patients with low back pain.

OBJECTIVE: this study aimed to correlate magnetic resonance (MR) findings and discography with pain response at provocative discography in patients with low back pain.

METHODS: ninety-three patients who underwent MR imaging of the lumbar spine and subsequent provocation discography as part of a clinical evaluation of low back pain were enrolled in the study. MR images were then evaluated for disc degeneration, high-intensity zone (HIZ), and endplate abnormalities. In the procedure of discography, concordant pain was denoted as positive, whereas discordant pain and no pain were denoted as negative. Finally, MR and discographic findings were analyzed by w2 test based on results of concordant pain.

RESULTS: discography was conducted on 256 discs successfully, 116 discs of which presented with concordant pain, and the others presented with discordant pain. There were 141 discs we reevaluated as Grade I-III on MR images, 17 of which presented with concordant pain; 115 were evaluated as Grade IV-V, 99 of which presented with concordant pain. HIZ was found in 60 discs,52 of which had concordant pain. The endplate abnormalities we reobserved in 58 discs, 51 of which manifested concordant pain. Concordant pain was significant correlated with Type IV-V discs on discography (w2=144.08, r=0.60, P<0.01), Grade IV-V disc degeneration on MR image (w2=137.11, r=0.59, P<0.01), the presence of HIZ (w2=51.93, r=0.41, P<0.01), and endplate abnormalities (w2=52.76, r=0.41, P<0.01).

DISCUSSION: disc degeneration grades on MR imaging showedan association with discographic grades. Type IV-V discs on discography, Grade IV-V disc on MR images, the presence of HIZ,and endplate abnormalities might indicate discogenic pain inpatients with chronic low back pain.