Clinical and imaging characteristics of cervical ossification of the posterior longitudinal ligament and factors influencing its severity: a retrospective cross-sectional study

Abstract Background Although the prevalence of cervical ossification of the posterior longitudinal ligament (OPLL) and its risk factors for onset and postoperative progression have been well documented, a comprehensive profile of patients with this condition remains lacking, and the determinants of its radiological severity are poorly understood. This study, therefore, aimed to delineate the clinical and imaging characteristics of cervical OPLL and to identify factors influencing its severity. Methods We retrospectively reviewed patients hospitalized in our hospital between January 2010 and December 2019 for degenerative cervical myelopathy (DCM), degenerative cervical radiculopathy (DCR), or cervical spinal cord injuries (CSCI). After screening for patients with cervical OPLL, their demographic, clinical, and imaging data were analyzed. The impact of various factors on the severity of OPLL was assessed, using the maximum occupying ratio and the number of involved segments as evaluation criteria. Results Among patients hospitalized for DCM, DCR, and CSCI, the prevalence of OPLL was 18.0% (547 of 3035), predominantly in middle-aged/elderly males. High rates of overweight (39.2%), hypertension (40.2%), and diabetes (21.2%) were observed. C5 (69.7%) and C6 (60.7%) were the most affected levels. Gender, BMI, diabetes, hypertension, and rheumatoid diseases were identified as factors influencing the severity of cervical OPLL. Conclusion This study provides a comprehensive characterization of the demographic, clinical, and imaging features of cervical OPLL and further identifies key factors associated with its severity. These findings may facilitate clinical risk stratification and offer new insights into the pathogenic mechanisms underlying OPLL progression.