Correlation of Cervical Disc Degeneration with Sagittal Alignments of Cervical Spine

ABSTRACT

OBJECTIVE: To determine the relationship between cervical sagittal parameters and the degree of the cervical disc degeneration at each cervical level by using cervical plain radiographs and disc degeneration grading.METHOD: This study analyzed 110 patients with posterior neck pain. Cervical radiographic measurements included the occipito-cervical (O~C2) angle; sagittal Cobb angles of C1~C2, C2~C7; and sagittal vertical axis (SVA) of C1~C7 and C2~C7. The degenerations of cervical discs at each level were evaluated through Pfirrmann grading system by magnetic resonance images of the cervical spine. The correlations between the cervical sagittal measurements and the disc degeneration at each level were analyzed by Spearman's correlation.RESULTS: A significant correlation was found for the C2~C7 angle with disc degenerations at C2~C6 levels. O~C2 angle was correlated significantly with disc degenerations at C2~C4 and C5~C7 levels. There was significant correlation between C1~C2 angle and disc degeneration at C6~C7 level. No significant relationship was found between the cervical SVA and the cervical disc degeneration at all cervical levels.CONCLUSION: Cervical sagittal parameters representing cervical angles (C2~C7, O~C2, and C1~C2 angles) were significantly correlated with the degree of the cervical disc degeneration. These findings suggest that the loss of the natural cervical lordosis rather than loss of natural SVA could be correlated with progression of the cervical disc degeneration.