Comparison of Anterior Controllable Antedisplacement and Fusion (ACAF) with Posterior Laminoplasty in the Treatment of Multilevel Cervical Ossification of the Posterior Longitudinal Ligament: A Prospective, Randomized and Control Study with at Least One-year Follow Up

STUDY DESIGN: A prospective, randomized, controlled study. OBJECTIVE: To compare anterior controllable antidisplacement and fusion (ACAF) with laminoplasty in the treatment of multilevel ossification of the posterior longitudinal ligament (OPLL), and evaluate the efficacy and safety of this procedure. SUMMARY OF BACKGROUND DATA: The optimal approach for the treatment of OPLL still remains controversial. Both anterior and posterior approaches have their advantages and disadvantages. METHODS: Between September 2016 and April 2018, a total of 80 patients with multilevel OPLL were randomized in a 1:1 ratio to ACAF group and laminoplasty group. All patients were followed up at least one year. Clinical and radiological results were compared between ACAF group and laminoplasty group. RESULTS: ACAF took a longer operation time. C5 palsy and axial pain occurred more commonly in laminoplasty group, whereas dysphagia and hoarseness appeared easily in ACAF group. At one-year follow-up, the final JOA score and RR were significant higher in ACAF group than those in laminoplasty group, when OR was not less than 60%, or K-line was negative. ACAF was also good at preservation of cervical lordosis and sagittal balance, but ROM of cervical spine in both groups decreased significantly. CONCLUSIONS: Generally speaking, ACAF is a safe and effective alternative for multilevel OPLL. Compared with laminoplasty, ACAF is more effective in the cases when OR is not less than 60%, or K-line is negative. LEVEL OF EVIDENCE: 2.