Fig. 4

Computed tomography images of the ossification of the posterior longitudinal ligament of the cervical thoracic spine on 21 November 2017. a The arrows indicate the ossification of the posterior longitudinal ligament of the third cervical vertebra, b the fourth cervical vertebra, c the third to the fourth cervical vertebrae, d the fourth thoracic vertebra, and e the fifth to the sixth thoracic vertebra