Serial Radiographic Evolution and All-Cause Mortality in Older Adults with Isolated Type II Odontoid Fractures: A 15-Year Single-Center Cohort Study

Study Design Retrospective cohort study. Objectives To characterize serial radiographic evolution after operative and non-operative management of isolated type II odontoid fractures in older adults and examine all-cause mortality. Methods Adults aged ≥65 years with isolated type II odontoid fractures treated at a Level I trauma center between 2010 and 2025 were included. Serial fracture displacement, angulation, and cervical alignment were assessed through 6 months. Mixed-effects models evaluated longitudinal changes, with fixation-technique comparisons explored within the operative subgroup. All-cause mortality from definitive treatment initiation was assessed using Kaplan–Meier analysis and age-adjusted Cox regression. Results Eighty-six patients were included: 33 operative and 53 non-operative. Among patients with available follow-up imaging, operative reduction was maintained, and no statistically significant progressive displacement or angulation was detected after non-operative management. No significant timepoint-by-technique interaction was detected for displacement (p=0.092) or angulation (p=0.823). Fifty deaths occurred. Non-operative management was not significantly associated with mortality compared with operative treatment (HR 0.93, 95% CI 0.51–1.70; p=0.806), whereas increasing age was independently associated with mortality (HR 1.09 per year, 95% CI 1.05–1.13; p<0.0001). Including calendar year did not materially alter the treatment estimate (HR 0.88, 95% CI 0.48–1.63; p=0.688). Conclusions Through 6 months, operative reduction was maintained and no statistically significant radiographic progression was detected after non-operative management among patients with available imaging. All-cause mortality was associated with age, whereas no significant association with treatment strategy was detected. These findings do not establish treatment superiority or equivalence.