Effect of Modic changes on spinal canal stenosis and segmental motion in cervical spine

Few studies have reported the characteristics of Modic changes (MCs) in the cervical spine in contrast to the lumbar spine. The purpose of this study was to identify the prevalence of MCs in the cervical spine and to elucidate the relationship of MCs with spinal canal stenosis and angular motion. 437 consecutive, symptomatic patients with neck pain with or without neurogenic symptoms were included in this study. MRI in multiple positions was performed with dynamic motion of the cervical spine in upright, weight-bearing neutral, flexion and extension positions. Type of MC, intervertebral disc degeneration grade, spinal cord compression grade and sagittal angular motion between flexion and extension for each segment from C2-3 to C6-7 were evaluated. MCs were observed in 84 out of 437 patients (19.2 %) and in 109 out of 2,185 motion segments (5.0 %) with type 2 changes predominating. Disc degeneration grades and spinal cord compression grades of segments with MCs were significantly higher than those without MCs. Sagittal angular motion of segments with MCs were significantly lower than those without MCs. Multiple logistic regression analysis revealed that significantly elevated odds ratios for MCs were observed in segments with severe disc degeneration, severe spinal canal compression and less angular motion. The cervical segments with MCs were significantly more likely to have disc degeneration and spinal canal stenosis. In addition, the segments with MCs had significantly less angular motion, which suggests MCs may correlate with loss of mobility.