Clinical study of anterior controllable antedisplacement and fusion for the treatment of cervical ossification of posterior longitudinal ligament

Objective To investigate the clinical effect of anterior controllable antedisplacement and fusion (ACAF) for the treatment of ossification of the posterior longitudinal ligament (OPLL) of the cervical spine. Methods The data of 45 cases with cervical posterior longitudinal ligament ossification treated by ACAF from March 2017 to October 2017 were retrospectively analyzed, including 25 males and 20 females, age 45-68 years, average 57.5 years. There were 18 cases involving C3 vertebral body, 30 cases involving C4 vertebral body, 40 cases involving C5 vertebral body, 34 cases involving C6 vertebral body, and 7 cases involving C7 vertebral body. The function of the neural function was evaluated by the Japanese Orthopaedic Association (JOA) scoring system at preoperation and latest follow-up. The curvature of the cervical spine was measured on the lateral X-ray film of the cervical spine, the maximum occupying ratio of the spinal canal was measured on the cross section of the CT scan, and compression of the cervical spinal cord was evaluated by the cervical MRI. Results Patients were followed up for 3 to 6 months (average, 3.9 months). The improvement of neurological function was obtained in all the patients. The JOA score improvement rate at the latest follow-up was 71.3%±9.6%. The cervical lordosis was improved from preoperative 4.5°±3.8° to 10.3°±4.8° at the latest follow-up. The canal stenosis ratio was decreased from preoperative 54.3%±8.2% to 12.5%±5.3% at the latest follow-up. MRI showed that the cervical spinal cord was adequately decompressed in situ. No specific complications were identified that were associated with this technique. Conclusion The present study elaborates the surgical tips and demonstrates the satisfactory outcome of ACAF for the treatment of OPLL. This novel technique has the potential to serve as an alternative surgical technique for the treatment of cervical OPLL. Key words: Cervical vertebrae; Ossification of posterior longitudinal ligament; Treatment outcome