Cohort study of cervical ossification of posterior longitudinal ligament in a Korean populations: Demographics of prevalence, surgical treatment, and disability

Objective: To investigate the demographic characteristics of cervical ossification of posterior longitudinal ligament (OPLL) including prevalence, surgical treatment, and disability in Korean population using Korean National Health Insurance Service National Sample Cohort (NHIS-NSC) data, and to analyze association between accessibility for surgical treatment and socioeconomic factors. Patients and Methods: A population-based cohort study was conducted using stratified representative sampling from NHIS-NSC data from the year 2002 to 2013. We analyzed prevalence and distribution of cervical OPLL according to age, sex, and socioeconomic factors. Multiple logistic regression analysis was conducted to investigate associations between independent variables and the rate of surgical treatment. Results: The overall prevalence of cervical OPLL was 190 per 100,000 people in Korea, and 11.4% of male patients and 4.0% of female patients received surgical treatment. Logistic regression analysis revealed that male patients received more surgical treatment than did female patients, also income level and residential area influence the rate of surgical treatment in females after adjustment of covariates (p< 0.05). Disability rate associated with cervical OPLL was 2.27% in male and 0.99% in female patients. Conclusion: In this cohort study, the prevalence of cervical OPLL was 190 per 100,000 people. Male patients received more surgery, and disability rate of male was higher than female patients. Although surgical treatment is covered by medical insurance in Korea, socioeconomic factors such as income level and residential area influence the treatment plans in females. These findings can help in the understanding of disease progression and can inform surgical treatment plans to reduce disability.