Modic changes associated with greater pain relief following anesthetization of the adjacent lumbar intervertebral disc: A retrospective study of chronic low back pain patients.

PURPOSE:To assess the correlation between the degree of pain relief following discoblock and the presence and type of adjacent Modic changes (MC). METHOD:We retrospectively analyzed chronic low back pain (LBP) patients whose pain was suspected to originate from a specific lumbar intervertebral disc (IVD) based on a spine orthopedist's clinical evaluation and magnetic resonance imaging (MRI). Thus, patients were selected to undergo discoblock. We calculated the degree of pain relief following discoblock on Numerical Rating Scale (ΔNRS) and analyzed the MRIs on the basis of MC presence and type on the lumbar spinal segment in question. We assessed the differences in ΔNRS between the groups with absent and present MC and the groups of MC subtypes. RESULTS:Forty-five patients were included in the present study, all of whom underwent discoblock at a single level. The total MC prevalence was 77.8 % (35 patients); pure or dominant MC type 1 (MC1 group) 35.6 % (16 patients); and pure or dominant MC type 2 (MC2 group) 42.2 % (19 patients). ΔNRS was significantly greater in the group with MC compared to the group without MC (median ΔNRS -5.0 vs -2.5, respectively, P = 0.043). In pairwise comparisons, a significant difference in ΔNRS was found between the MC1 group and the group without MC (median ΔNRS -5.0 vs -2.5, respectively, P = 0.012). CONCLUSIONS:We propose that MC type 1 are associated with lumbar spinal pain, and that the pain arises at least partly from the adjacent IVD or endplate.