Mortality From Combined Fractures of the Atlas (C1) and Axis (C2) in Adults

Study design A retrospective case report of all upper cervical spine fractures diagnosed by CT imaging between 01/01/2013 and 31/12/2015 in NHS Greater Glasgow and Clyde, Scotland. Objective To compare the mortality following combined fractures of the atlas and axis to that of isolated fractures of either vertebra. Background The mortality from axis fractures is well documented in the literature. However, a combined fracture of the atlas and axis is seldom reported, leading to relatively unknown outcomes and mortality. Methods A total of 171 patients with atlas and/or axis fractures. Thirty-three presented with concurrent lower cervical spine fractures and were excluded from further analysis. Kaplan-Meier curves were used to compare survivorship between 108 patients with isolated and 30 with combined fractures. Similar analysis adjusted for comorbidities, including dementia and previous fragility fractures. Results Patients were followed up for 47.3±10.3 months (SD). Patients with isolated atlas fractures were significantly younger than those with an axis or combined fracture. Nearly half (8/17) of combined fracture mortalities occurred within the first 120 days. The mortality at 120 days was 26.7% in the combined fractures group and 18.5% in the isolated fracture group. There was no significant difference in the 120-day and overall mortality between these injury patterns. Furthermore, cognitive impairment and previous fragility fractures bore no significant impact on mortality. Nevertheless, mortality in the combined fracture group with previous fragility fractures did trend to shorter survivorship. Conclusions Patients with combined fractures are older and with the ever-increasing elderly population, the incidence of these injuries is expected to rise. While our data show that the 120-day mortality is proportionally higher in the combined fractures group, no long-term statistically significant difference is demonstrated. This evidence contests the notion that combined fractures of the atlas and axis have higher mortality than isolated injuries of either cervical vertebra.