Fig. 2.

Preoperative and postoperative X-ray, CT and MRI of multilevel cervical spondylotic myelopathy treated by different posterior operations. a A 67-year-old female patient underwent C4 to C7 laminoplasty, whose preoperative JOA score was 8. In the final follow-up of 9.5 years, the loss of CI was 2.4 %, final follow-up JOA score was 14 and NDI score was 23. b A 56-year-old male patient underwent C4 to C6 laminectomy, whose preoperative JOA score was 7. In the final follow-up of 7.5 years, the loss of CI was 3.7 %, final follow-up JOA score was 13 and NDI score was 27. c A 61-year-old male patient underwent C3 to C7 laminectomy with lateral mass screw fixation, whose preoperative JOA score was 8. In the final follow-up of 8 years, the loss of CI was 0.4 %, final follow-up JOA score was 16 and NDI score was 2