Discogentic lumbar pain: association with MRI and discography / 中华放射学杂志

ABSTRACT

Objective To evaluate the correlation between MRI and X-Ray discography findings and pain response at provocative discography in patients with discogenic back pain. Methods Two hundred and fifty-six lumbar intervertebral discs in 93 patients who underwent MRI and X-Ray discography were included in this study. MR images were retrospectively evaluated regarding disc degeneration, endplate abnormalities and high intensity zone. Disc degeneration was graded according to the modified criteria of Pearce, et el. Evaluation of disc morphology was performed with X-Ray discography by using the classification of Adams, et al. Endplates and adjacent bone marrow abnormalities were classified according to Modic,et al. During discography concordant pain was regarded as positive, whereas discordant pain and no pain were regarded as negative. The data were analyzed using the Chi-squnre test. Results There were 116 discs with concordant pain and 140 discs with discordant pain or no pain. Of 256 discs on discography, 17 discs were type Ⅰ17(6.6%),type Ⅱ were 25(9.8%),type Ⅲ were 91(35.5%), type Ⅳ were 77(30.1%) and type Ⅴ were 46(18.0% ). On MR images, discs of grade Ⅰ were 23 (9.0%) ,grade Ⅱ were 34(13.3%), grade Ⅲ were 84(32.8%), grade Ⅳ were 85 (33.2%) and grade Ⅴ were 30(11.7%). There was positive correlation between Pearce graded of MRI and classification of Adams of discography (r=0.62, X2 =160.87,P <0.01).In 123 discs of type Ⅳ to type Ⅴ on discography, 104 discs were with concordant pain. There was positive correlation between type Ⅳ-Ⅴ and concordant pain( r=0.60, X2 = 144.08, P < 0.01). In 115 discs of Ⅳ-Ⅴ grade degeneration, 99 discs presented with concordant pain. There was positive correlation between Ⅳ-Ⅴ grade disc degeneration and concordant作者单位510120 广州,中山大学附属第二医院放射科 pain(r = 0.59, X2 = 137.11, P <0.01 ). In 60 discs with high intensity zone(HIZ), 52 discs presented with concordant pain. There was positive correlation between HIZ and concordant pain ( r=0.41, X2= 51.93, P <0.01 ). In 58 discs with endplate degeneration, 51 presented with concordant pain. There was positive correlation between Modic degeneration and concordant pain ( r = 0.41, X2= 52.76, P < 0.01 ). Conclusion In patients with chronic low back pain, MR imaging may present moderate to severe disc degeneration, high intensity zone, endplates and adjacent bone marrow abnormalities. MR findings with concordant pain can raise the diagnostic possibility of discogenic lumbar pain. Typical discography findings, fissured or ruptured disc, with concordant pain are important diagnostic evidence for discogenic lumbar pain.