Conservative versus Surgical Treatment for Odontoid Fracture: Is the Surgical Treatment Harmful? Systematic Review and Meta-Analysis

International audienceBackground: Odontoid fracture is a common injury especially in elderly people. Despite some recent studies arguing in favor of surgery, the best treatment is still being debated.Objective: We systematically review and analyze the comparative literature between surgical and conservative treatments of odontoid fractures.Methods: We systematically searched Medline and the Cochrane Library for studies reported from January 1990 to May 2019 in English. Comparative studies evaluating the results of surgical and conservative treatments for odontoid fractures were eligible for inclusion. Combined relative risks (RRs) for mortality at last follow-up, union or nonunion rates, and complications were calculated. Methodological quality was assessed using the Newcastle-Ottawa Scale. Influence of age and year of publication on treatment effect was explored using a meta-regression analysis.Results: A total of 1438 articles were identified, of which 30 articles with 2463 patients were eligible for inclusion. There was a trend toward lower mortality in the surgical group (RR, 0.80; 95% confidence interval [CI], 0.63-1.02). Nonunion rates (RR, 0.41; 95% CI, 0.28-0.6) were lower in the surgical group. Union rates were higher in the surgical group (RR, 1.26; 95% CI, 1.11-1.45). No significant influence of age or year of publication on treatment effect was found.Conclusions: Based on this meta-analysis of nonrandomized comparative studies, surgical treatment seems not to be inferior to conservative treatments. The conclusions of this study remain limited by the low quality of the evidence available. Randomized controlled studies are required