Zero-profile implant versus conventional cage-plate implant in anterior cervical discectomy and fusion for the treatment of degenerative cervical spondylosis: a meta-analysis.

Zero-profile implant has become more and more popular in anterior cervical discectomy and fusion (ACDF) for the treatment of degenerative cervical spondylosis. However, there was no enough evidence judging its efficiency and safety. The aim of this analysis was to evaluate the efficacy and safety of Zero-profile implant compared with conventional cage-plate (CCP) in ACDF. All studies directly comparing the outcomes between the Zero-profile implant and CCP implant in ACDF were included, and the search strategy followed the requirements of the Cochrane Library Handbook. Two of the authors extracted relevant data and checked the accuracy independently using standardized data collection form. Seven studies involving 560 patients were included, 262 in the Zero-profile group and 298 in the CCP group. Zero-profile implant had a lower rate of postoperative dysphagia at 2 weeks, 6 months, and 1 year (p = 0.0002, p = 0.008, and p = 0.001, respectively) than CCP implant. Zero-profile also reduced blood loss (p = 0.0001), while operation time and incidence of postoperative transient dysphagia had no statistical significance (p = 0.92, p = 0.42, respectively) between two groups. Based on the results of our analysis, the application of Zero-profile implant in ACDF had a lower rate of postoperative dysphagia at 2 weeks, 6 months, and 1 year than CCP implant. Zero-profile implant also had fewer blood loss during operation. More rigorous and adequately powered prospective randomized controlled trials with larger sample size are required to elucidate a more objective outcome.