Comparison of two anterior fusion methods in two-level cervical spondylosis myelopathy: a meta-analysis

Objective The aim of this study was to evaluate the efficacy and safety of anterior cervical corpectomy and fusion (ACCF) and anterior cervical discectomy and fusion (ACDF) for treating two-adjacent-level cervical spondylosis myelopathy (CSM). Design A meta-analysis of the two anterior fusion methods was conducted. The electronic databases of PubMed, the Cochrane Central Register of Controlled Trials, ScienceDirect, CNKI, WANFANG DATA and CQVIP were searched. Quality assessment of the included studies was evaluated using the Cochrane Risk of Bias Tool and the Methodological Index for Non-Randomised Studies criteria. Pooled risk ratios of dichotomous outcomes and standardised mean differences (SMDs) of continuous outcomes were generated. Using the χ2 and I2 tests, the statistical heterogeneity was assessed. Subgroup and sensitivity analyses were also performed. Participants Nine eligible trials with a total of 631 patients and a male-to-female ratio of 1.38:1 were included in this meta-analysis. Inclusion criteria Randomised controlled trials (RCTs) and non-randomised controlled trials that adopted ACCF and ACDF to treat two-adjacent-level CSM were included. Results No significant differences were identified between the two groups regarding hospital stay, the Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS) scores for neck and arm pain, total cervical range of motion (ROM), fusion ROM, fusion rate, adjacent-level ossification and complications, while ACDF had significantly less bleeding (SMD=1.14, 95% CI (0.74 to 1.53)); a shorter operation time (SMD=1.13, 95% CI (0.82 to 1.45)); greater cervical lordosis, total cervical (SMD=−2.95, 95% CI (−4.79 to −1.12)) and fused segment (SMD=−2.24, 95% CI (−3.31 to −1.17)); higher segmental height (SMD=−0.68, 95% CI (−1.03 to −0.34)) and less graft subsidence (SMD=0.40, 95% CI (0.06 to 0.75)) compared to ACCF. Conclusions The results suggested that ACDF has more advantages compared to ACCF. However, additional high-quality RCTs and a longer follow-up duration are needed.