Effect of Different Types of Modic Changes on Segmental Motion and Disc Degeneration in Cervical Spine

Abstract

Background: Few studies have reported the segmental motion characteristics of different types of Modic changes (MCs) in the cervical spine in contrast to the lumbar spine. Considering the close relationship between MCs and disc degeneration (DD), this study is designed to elucidate the relationship of MCs with DD and DD-based angular motion in the cervical spine.Methods: MRI of C2/3~C6/7 from 594 patients were reviewed and those with MCs were selected and evaluated. MCs were defined as type 0, I, II, and III, and the grade of DD was classified from A to E (recorded from 1 to 5 points) as previously reported. DD score of each segment (sDD), total sDD of the entire cervical spine (tDD), and VAS score (neck pain) of each patient with MC were also recorded. Cervical lordosis (CL), C7 slope (C7S), segmental angular motion (sROM) and total angular motion of the entire cervical spine (tROM) were calculated from X-ray images.Results: Totally 135 MC segments were evaluated. In the two groups of DD D and DD E, the sROM of MC I and III segments are smaller than that of MC 0 segments, and the sROM of MC II segments are similar to that of MC 0. In addition, MC I segments present smaller sROM than that of MC II in the group of DD E, and their sROM are larger than that of MC III in the group of DD D. No difference is found in tROM between the patients with MC I, II and III. Our results also show that MC I and III segments are associated with high sDD and tDD scores. Finally, the patients with MC I have larger CL and C7S than those with MC III, and there is no statistical difference in VAS scores of neck pain between the patients with MC I, II and III. Conclusions: In the cervical spine, both MC I and III indicate decreased segmental angular motion and high disc degeneration grade. Cervical MCs may not be a sign of unstable neck pain or an indication for interbody fusion.