Hypovitaminosis D and Cervical Disk Herniation among Adults Undergoing Spine Surgery

Study Design Single-center, retrospective study. Objective Suboptimal concentrations of vitamin D have been linked to hip and knee osteoarthritis in large, population-based cohort studies. We sought to examine the association of vitamin D levels with intervertebral disk disease. Methods From January 2010 through May 2011, 91 consecutive, eligible adult spine surgery patients who had undergone cervical magnetic resonance imaging (MRI) and preoperative serum 25-hydroxyvitamin D (s25D) measurement were retrospectively included. MRI was read for C2-T1 disk herniation and degeneration (grades I to V). Logistic regressions were performed. Results Compared with the 384 disks of nondeficient patients, 162 disks of vitamin D-deficient (< 20 ng/mL) patients were more frequently herniated (40% versus 27%, p = 0.004); deficiency was not predictive of individual disk grade (unadjusted odds ratio [uOR] = 0.98, p = 0.817). On regression analysis, deficiency was associated with increased number of herniations per patient (uOR = 2.17, 95% confidence interval [CI] = 1.22 to 3.87, p = 0.009; adjusted odds ratio [aOR] = 2.12, 95% CI = 1.11 to 4.03, p = 0.023). When disks were analyzed individually, and levels (e.g., C5 to C6), additionally controlled for, deficiency correlated with greater likelihood of herniation per disk (uOR = 1.81, 95% CI = 1.22 to 2.66, p = 0.003; aOR = 2.06, 95% CI = 1.25 to 3.41, p = 0.005). Conclusion Among adults undergoing spine surgery at our institution, vitamin D deficiency was associated with cervical disk herniation. Considering the current epidemics of vitamin D insufficiency and neck pain, further investigation is warranted, as these data were retrospectively collected and subject to sampling bias.