Anterior cervical discectomy and fusion vs posterior laminoplasty for the treatment of myelopathy due to two-level localized ossification of the posterior longitudinal ligament

We conducted a retrospective study to compare the clinical and radiological results of anterior cervical discectomy and fusion (ACDF) and posterior laminoplasty for two-level localized ossification of the posterior longitudinal ligament (OPLL). ACDF and posterior laminoplasty are performed for localized OPLL at the disc and vertebral body levels, respectively. Eighty six patients with two-level localized OPLL who underwent surgery from January 2011 to December 2016 were retrospectively investigated (41, ACDF group; 45, laminoplasty group). Clinical outcomes were reviewed, and radiologic results such as occupying ratio (OR), space available in the spinal cord, cranial and caudal OPLL-to-disc distance (ODD)/posterior body height (PBH) ratios, segmental angle, C2–C7 Cobb angle, T1 slope, C2–C7 sagittal vertical axis (SVA), and range of motion were investigated. Patients were followed-up for an average of 42.7 ± 10.5 months. Clinical outcomes, postoperative OR, and space available in the spinal cord were significantly improved at the final follow-up in both groups. Preoperatively, the OR and cranial and caudal ODD/PBH ratios were not significantly different between the groups. Compared to pre-operative values, differences in the segmental and C2–C7 Cobb angles at the final follow-up were statistically significant for the ACDF group (P