Modified axial computed tomography classification of cervical ossification of the posterior longitudinal ligament: selecting the optimal operating procedure and enhancing the accuracy of prognosis.

Background: Cervical ossification of the posterior longitudinal ligament (OPLL) causes spinal cord compression, which can lead to myelopathy or radiculopathy. Non-surgical treatments have little effect on this condition. Current OPLL classification systems offer little guidance on the selection of an appropriate operating procedure.