Risk Factors for Failure of Non-operative Management in Isolated Unilateral Non-displaced Facet Fractures of the Subaxial Cervical Spine: Systematic Review and Meta-Analysis

Study Design: systematic review. Objective: To evaluate risk factors associated with failure of non-operative management of isolated unilateral facet fractures of the subaxial cervical spine in neurologically intact patients. Methods: A systematic review of the PubMed, Embase, LILACS, and Cochrane Library databases was conducted in order to determine risk factors associated with failure of non-operative management in isolated unilateral facet fractures of the subaxial cervical spine without facet and/or vertebral displacement, in neurologically intact patients. Our research was in line with the PRISMA Statement and registered on PROSPERO (CRD42023405699). Results: A total of 1639 studies were identified through a database search on May 5, 2023. In total, 7 studies from the databases were included, along with 1 study found through a manual citation search. The evidence showed high clinical heterogeneity, a serious risk of bias according to the ROBINS-I tool, and a predominance of retrospective cohort studies. In comparison to less complex facet fractures, lateral floating mass fractures were found to have 5.41 times higher odds of failure of non-operative management (OR = 5.41; 95% CI = 1.32, 22.19). We calculated the potential association between lower absolute fracture height and non-operative treatment success [Fracture height (percentage) Mean Difference = −17.51 (−28.22, −6.79 95% CI); Absolute height Mean Difference: −0.46 (−0.60, −0.31 95% CI)]. Other risk factors were not included in the meta-analysis due to lack of data. The level of certainty was rated as “very low”. Conclusions: Lateral floating mass cervical facet fractures and larger fracture fragment size (measured either in absolute terms or as a percentage) are significant risk factors for failure of non-operative treatment.