Comparison of Laminoplasty and Posterior Fusion Surgery for Cervical Ossification of Posterior Longitudinal Ligament
Abstract This prospective multicenter study formed by the Japanese Ministry of Health, Labour and Welfare at 27 institutions aimed to compare postoperative outcomes between laminoplasty (LM) and posterior fusion (PF) for cervical ossification of the posterior longitudinal ligament (OPLL). Controversy exists regarding the role of instrumented fusion in the context of posterior surgical decompression for OPLL. Among the 479 patients enrolled, 189 (137 and 52 patients with LM and PF, respectively) were included and evaluated using the Japanese Orthopaedic Association (JOA) scores, the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), and radiographical measurements. Basic demographic and radiographical data were reviewed, and the propensity to choose a surgical procedure was calculated. Preoperatively, patient backgrounds, radiographical measurements (K-line or cervical alignment on X-ray, OPLL occupation ratio on computed tomography, and increased signal intensity change on magnetic resonance imaging), or clinical status (JOA score and JOACMEQ) after adjustments showed no significant differences. The overall risk of perioperative complications was lower in LM (odds ratio [OR] 0.40, p = 0.006), and C5 palsy was significantly lower in LM (OR 0.11, p = 0.0002) than in PF. The range of motion (20.91° ± 1.05° and 9.38° ± 1.24°, p < 0.0001) in patients with PF was significantly smaller than in those with LM. However, multivariable logistic regression analysis showed no significant difference in JOA score, JOA recovery rate, or JOACMEQ improvement at two years. In contrast, OPLL progression was greater in LM group than in the PF group (OR 2.73, p = 0.0002). LM and PF for cervical myelopathy due to OPLL resulted in comparable postoperative outcomes at two years after surgery.