Comparison of anterior and posterior approaches for the treatment of cervical ossification of the posterior longitudinal ligament: a meta-analysis of 28 cohort studies.

At present, the choice of approach for the surgical treatment of cervical ossification of the posterior longitudinal ligament (OPLL) remains controversial. We performed this meta-analysis to compare the efficacy of the anterior and posterior approaches in the treatment of cervical OPLL. PubMed, EMBASE and the Cochrane Library were systematically searched for all eligible articles as of August 3, 2023, without any publication date restrictions. We used the random effects model to pool standardized mean differences (SMDs) or odds ratios (ORs) with 95% confidence intervals (CIs). We conducted subgroup analyses to explore the potential sources of heterogeneity, and sensitivity analyses were used to evaluate the robustness of the findings via the leave-one-out procedure. In addition, we evaluated publication bias by observing the symmetry of the funnel plot and using Egger's test, and the trim-and-fill method was employed to A total of 28 studies including 6,324 participants met the inclusion criteria. The meta-analysis revealed that, compared with the posterior approach, the anterior approach was significantly associated with a superior recovery rate (SMD, 0.83; 95% CI, 0.41 to 1.25), a greater number of patients with a recovery rate ≥ 50% (OR, 2.13; 95% CI, 1.16 to 3.92), higher Japanese Orthopaedic Association (JOA) scores (SMD, 0.62; 95% CI, 0.31 to 0.94), and better recovery of cervical lordosis (SMD, 1.83; 95% CI, 0.95 to 2.72). Furthermore, the results revealed that the complication rate (OR, 1.45; 95% CI, 1.01 to 2.09) with the anterior approach was significantly greater than that with the posterior approach. However, our study revealed no significant differences between the two surgical groups in terms of the postoperative visual analogue scale (VAS) score, postoperative space available for the spinal cord, postoperative range of motion of the cervical spine, duration of symptoms, operation time, blood loss, or length of stay. The anterior approach is superior to the posterior approach in terms of the postoperative recovery rate, the number of patients with a recovery rate ≥ 50%, JOA scores, and recovery of cervical lordosis. Combined with the results of the above outcome and subgroup analysis, we advocate for the anterior approach in patients with a canal-occupying ratio exceeding 50% or 60%.