Evaluation of Post-Operative Outcomes in Patients with Dementia Undergoing Ankle Fracture Open Reduction and Internal Fixation

Research Type: Level 3 - Retrospective cohort study, Case-control study, Meta-analysis of Level 3 studies Introduction/Purpose: Dementia affects over 55 million people worldwide and is associated with an increase in postoperative complications following a variety of surgeies. Although its impact has been studied in other surgical populations, there is very limited data on the impact of dementia on the outcomes of ankle fracture open reduction and internal fixation (ORIF). This study aims to evaluate the effects of preoperative dementia on clinical outcomes following ankle fracture ORIF. Methods: This retrospective study utilized the TriNetX database (2005-2025) to create two cohorts of patients undergoing ankle fracture ORIF. Cohort 1 consisted of patients who were preoperatively diagnosed with dementia, while cohort 2 consisted of controls without dementia. Propensity score matching was used at a 1:1 ratio based on preoperative demographic characteristics and comorbidities, in efforts to control for possible confounders. Following matching, each cohort consisted of 1,110 patients. Cohort 1 (70.4% female) had a mean age of 72.5 years (range 18-100), mean body mass index (BMI) of 30.1 kg/m2 (range 18.5-40), and mean follow-up duration of 606.6 days (range 180-1095.8). Cohort 2 (70.8% female) had a mean age of 72.9 years (range 18-100), mean BMI of 30.5 kg/m2 (range 18.5-40), and mean follow-up duration of 653.8 days (range 180-1095.8). Results: At 6 months, patients with dementia demonstrated statistically significantly increased risks of pneumonia (Risk Ratio [RR]: 1.739; 95% Confidence Interval [CI]: 1.048–2.885), urinary tract infection (UTI) (RR: 1.353; 95% CI: 1.000–1.830), and mortality (RR: 2.500; 95% CI: 1.409–4.437). However, the risk of post-traumatic arthritis was lower in the dementia cohort (Risk Difference [RD]: -0.009; 95% CI: -0.015 to -0.003; p = 0.002). At 2 years, dementia patients had a lower risk of conversion to a fusion (RD: -0.009; 95% CI: -0.015 to -0.003; p = 0.002). No differences in nonunion or malunion were observed between the two cohorts at any timepoint. Conclusion: Patients with dementia undergoing ankle fracture ORIF have increased risks pneumonia, UTIs, and especially postoperative mortality Patients and surgeons should be aware of these elevated risks in this population. Additional research is needed to better characterize this association and its clinical implications.