Clinical and Radiological Characteristics of Ossification of the Posterior Longitudinal Ligament of the Cervical Spine in Patients without Myelopathy: Results of a 1-year Pilot Study

AIM: We analyzed the demographics, clinical and radiological characteristics of non-myelopathic cervical ossification of the posterior longitudinal ligament (OPLL) patients. MATERIAL and METHODS: This study included 115 patients with cervical OPLL but without myelopathy. Demographic features of age, sex, and the nature of the patient's symptoms were evaluated. Clinically, visual analog scale (VAS) scores for the neck and arm, and Japanese Orthopaedic Association (JOA) scores were evaluated. Radiologically, the number of involved segments, type of OPLL, and the maximal compression ratio were analyzed using a computed tomography (CT) scan. The relationship between clinical scores and radiological parameters was analyzed. RESULTS: At the time of diagnosis, there was absence of symptoms in 23, axial neck pain in 44, radiculopathy in 40, and tingling sensation of fingers in 8. VAS score for the neck was 4.42 and that for the arm was 3.64. The mean JOA score was 16.13. Radiologically, the mean number of involved segments was 3.55. The type of OPLL mass was continuous, mixed, segmental, and local in 10, 43, 42, and 20 cases, respectively. The maximal compression ratio was 0.38. There was a significant relationship between the maximal compression ratio and the number of involved segments (p<0.001). No relationship was found between clinical symptoms, clinical scores, and radiological findings. CONCLUSION: Some non-myelopathic cervical OPLL patients showed no symptoms, some presented axial neck pain and radiculopathy. Radiologically, a significant relationship between the maximal compression ratio and the number of involved segments was found. However, there was no relationship between clinical symptoms and radiological findings in neurologically intact patients.