An International Multicenter Study to Assess Factors Associated with Successful Fusion in Children Undergoing Occiput to C2 Rigid Instrumentation and Fusion

Introduction: Studies investigating outcomes after pediatric occipital-cervical fusions are limited to small sample sizes. Currently, there is significant variation among pediatric spine surgeons regarding instrumentation, bone graft material and graft extenders, post-operative immobilization, and other factors. The purpose of this study was to identify factors associated with successful fusion in pediatric patients undergoing occiput to C2 posterior spinal instrumented fusion (PSF).

Methods: The Pediatric Spine Study Group (PSSG) registry was queried to identify patients
Results: Fusion failure was identified in 20/53 (38%) patients who required revision surgery (n = 5), had screw haloing or breakage on imaging (n = 12), or had absence of bridging bone on imaging (n = 3). Univariate analysis demonstrated that the use of structural autograft (p < 0.5), cabling to secure bone graft (p < 0.5), and use of BMP (p < 0.5) were associated with successful fusion. Down syndrome was not associated with failure of fusion. Logistic regression demonstrated that use of BMP and structural autograft were strong predictors of successful fusion, with odds ratios of 8.92 (p < 0.5) and 22.32 (p < 0.5), respectively.

Conclusion : Using a multicenter, international registry of pediatric patients undergoing occiput to C2 instrumented fusion, we identified the use of BMP and structural autograft as factors associated with successful fusion. Consideration toward these adjuncts should be considered during operative planning.