Traumatic atlas fracture patients comprise two subpopulations with distinct demographics and mechanisms of injury

Atlas fractures account for as much as 13% of cervical fractures, yet their epidemiology and its implications remain under-examined.We retrospectively analyzed 97 consecutive cases of isolated, traumatic atlas fractures at our institution over a 17-year period with respect to demographic, clinical, and outcomes data. Unique patient subsets were identified and compared across these parameters.The age of atlas fracture patients showed a bimodal distribution and strong goodness of fit, with one mean centered at an age of 30 years for patients age< 50 (R=0.9409) and mean age of 74 among patients age≥ 50 (R=0.8584). Young patients were more likely to have a high-risk mechanism of injury (57.8% vs. 11.5%, OR=10.49 [3.59, 29.65], p < 0.0001) and injuries while intoxicated (13.3% vs. 0%, OR ∞ [1.704, ∞], p = 0.0082). A greater portion of young patients were managed with halo (33.3% vs. 13.5%, OR=3.21 [1.20, 8.13, p = 0.0281]). Among patients who were managed with halo, a greater proportion had halo-related complications among patients age≥ 50 (57.1% vs. 6.7%, OR=18.67 [1.55, 239.1], p = 0.0207). The median age of atlas fractures increased by ~2.6 years annually (slope 2.637, p < 0.0001, R=0.8079).The atlas fracture patient population may comprise two distinct subpopulations, distinguished by differences in age and mechanism of injury that lead to divergent management decisions. While halo immobilization has a low rate of complications among patients age< 50, the complication among patients age≥ 50 was significantly higher. The median age of atlas fracture patients increased linearly during the study period, highlighting the importance of age-related differences in management.