Symptomatic ossification of the posterior longitudinal ligament of the cervical spine: pictorial essay

Symptomatic ossification of the posterior longitudinal ligament (OPLL) of the cervical spine is a rare but well-documented condition. It is the causative factor in up to 5% of cases presenting with cervical radiculopathy or myelopathy. Computed tomography is the modality of choice in showing the distinctive characteristics and extent of the disease. Magnetic resonance imaging (MRI) is sensitive in detecting cord compression and its attendant complications. Cervical OPLL commonly affects those of middle and advanced age, and the condition is noted to be particularly common in Japanese, although other racial groups are also affected. A 'mushroom' or 'hill' shape on axial CT typifies OPLL. A sharp radiolucent line separating the posterior vertebral margin from the superficial component of the ossified ligament is a characteristic feature.