The Effect of Segmental Hyper-Mobility on Development of Cervical Disc Degeneration: a Retrospective Study

Background The aging factor, which appears to be the result of chronic repetitive movement, has been identified as a crucial factor of spinal degenerative joint disease (DJD). However, there has been no study to evaluate the relationship between the amount of movement and the prevalence of DJD. Thus, the purpose of our study was to investigate the relationship between segmental mobility of the cervical spine and the prevalence of DJD, and to compare it with other known etiologic factors of DJD. Methods A retrospective analysis of cervical radiographs (neutral, flexion, and extension views) and MRI scans of 101 patients with neck pain (28 male, 72 female; mean age 51.51 ± 6.78 years) was conducted. Amount of segmental range of motion (ROM) from C2/3 to C6/7 was measured. Patients were categorized into three groups: No DJD, Single DJD, and Multiple DJD. To assess the association between segmental mobility angle, demographic factors and multiple DJD progression, one-way ANOVA and multiple linear regression analyses were performed. Results The middle cervical region exhibited the most extensive range of motion, exclusively the C4/5 segment demonstrating the highest mobility (12.70° ± 5.00°). The most prevalent site for DJD was C6/7 (75, 74.3%). Comparison of the groups by the ANOVA, distinct hyper-mobility pattern was the key factor : while the No-DJD group maintained stable motion at C4/5 (10.20°), both the single and multiple DJD groups exhibited a significant increase in hyper-mobility at this segment (p = 0.034). Multiple regression analysis adjusted for confounding factors revealed that C4/5 mobility was a significant independent predictor of multiple DJD progression (ß = 0.342, p = 0.003), whereas age, gender, and BMI did not show a significant effect. Conclusion The middle cervical segment (C4/5) showed the greatest range of motion and correlated with the highest prevalence of multiple DJD. Specifically, segmental hyper-mobility at the C4/5 level, characterized by distinct focal hyper-mobility, is strongly associated with the multiple progression of cervical DJD with this correlation outweighing the effect of age.