Efficacy and safety of Vertebral Body Sliding Osteotomy (VBSO) versus Anterior Cervical Corpectomy and Fusion (ACCF): A systematic review and meta-analysis.

Anterior cervical corpectomy and fusion (ACCF) is an established treatment for complex cervical myelopathy and ossification of the posterior longitudinal ligament (OPLL), yet it carries risks of dural injury and graft-related failure. Vertebral body sliding osteotomy (VBSO) is a novel technique that avoids direct OPLL manipulation by translating the vertebral body anteriorly to enlarge the spinal canal. Although early studies suggest VBSO may reduce complications, evidence remains limited to retrospective cohorts from the technique's developers, with no high-level synthesis directly comparing it to ACCF. We therefore conducted this meta-analysis to compare clinical outcomes, complications, and radiographic parameters between VBSO and ACCF, while critically evaluating the certainty of the evidence and its generalizability. A systematic search of PubMed, Embase, Scopus, the Cochrane Library, and Web of Science (through June 2025) identified four retrospective cohort studies (449 patients; VBSO n = 209, ACCF n = 240). A critical limitation of the included evidence is that all studies originated from a single institution (Asan Medical Center, Seoul, Korea) with overlapping enrollment periods (2006-2020), increasing the risk of duplicate patient cohorts. Furthermore, the first author (D.-H. Lee) is the same across all included studies, introducing substantial surgeon-expertise bias. Outcomes included neurological recovery, functional outcomes, complications, and radiographic parameters. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. Neurological recovery and functional outcomes were comparable between groups. ACCF showed slightly higher postoperative JOA scores (MD -0.59, 95% CI -0.96 to -0.22; p < 0.01), though the clinical relevance is uncertain. VBSO was associated with reduced risks of graft subsidence (RR 0.23; p < 0.01), pseudarthrosis (RR 0.25; p < 0.01), revision surgery (RR 0.17; p < 0.01), and neurological deterioration (RR 0.17; p = 0.02). CSF leakage appeared to be less frequent with VBSO, but the difference was not statistically significant. VBSO was also associated with greater postoperative cervical lordosis and shorter hospital stays. However, these findings must be interpreted with extreme caution: leave-one-out sensitivity analyses revealed that the results for postoperative JOA score, neurological deterioration, and pseudarthrosis were fragile and driven by a single large study, meaning these apparent advantages may not be robust. In addition, GRADE assessment revealed very low certainty across all assessed outcomes. Given the very low certainty of evidence, the preliminary nature of the available data, the fragility of several key findings, and the critical limitations of the underlying studies (single institution, overlapping patient cohorts, developer bias, and systematic imbalance in follow-up duration), the observed differences should be considered hypothesis-generating rather than definitive. VBSO should not be considered a proven superior alternative to ACCF based on the current evidence. Prospective, multicenter, international studies with balanced follow-up durations conducted by independent surgical teams are required before broader adoption can be recommended.