Fig. 2

Atlantoaxial dislocation (Type II), female, 51 years old. a, b Lateral and open-mouth view radiographs of cervical spine showed that the C2–C7 angle was 8°. c, d Flexion–extension radiographs of cervical spine indicated a partially reducible dislocation of the atlantoaxial joint. e, f CT scan of cervical spine also indicated the atlantoaxial dislocation. g One month after operation, lateral radiograph of cervical spine showed that the dislocation had been fully reduced, and the C2–C7 angle was 8°. h Seven months after operation, lateral radiograph of cervical spine showed the loss of subaxial lordosis and the C2–C7 angle was 2°