Preoperative malnutrition is associated with increased early complications and long-term mortality following pilon fracture ORIF: A retrospective cohort study

Malnutrition is a modifiable condition linked to poorer outcomes after orthopedic surgery. Its influence on perioperative and long-term results following pilon fracture open reduction and internal fixation (ORIF) remains uncertain. This study examined the association between preoperative malnutrition and postoperative complications and mortality in patients undergoing pilon fracture ORIF. A retrospective cohort study using the TriNetX US Collaborative Network identified adults who underwent pilon fracture ORIF (CPT 27827, 27828) between 2005 and 2023. Preoperative malnutrition was defined by abnormal laboratory markers within one year before surgery (albumin ≤3.5 g/dL, transferrin ≤204 mg/dL, or leukocyte count ≤1.5 × 10 3 /μL). Malnourished patients (n = 2,565) were propensity score matched 1:1 to controls from 17,883 eligible cases, yielding two groups of 2,396 with balanced demographics and comorbidities (standardized mean differences < 0.1). 90-day outcomes included readmission, emergency department visits, venous thromboembolism, renal, cardiac, and pulmonary events, infection, wound complications, and pneumonia. 2-year outcomes assessed mechanical failure, nonunion, malunion, revision, and mortality. Associations were expressed as risk ratios (RR) with 95% confidence intervals (CI). At 90 days, malnourished patients had significantly higher rates of readmission (13.0% vs. 6.7%; RR 1.94, p<0.001), infection (10.4% vs. 5.6%; RR 1.87, p<0.001), wound dehiscence (6.9% vs. 4.0%; RR 1.75, p<0.001), and pneumonia (4.8% vs. 1.5%; RR 3.08, p<0.001). Risks of thromboembolic, renal, and cardiac events were also elevated. At two years, malnutrition increased the risks of mechanical complications (RR 1.47, p=0.001), revision for malunion or nonunion (RR 1.39, p=0.005), and mortality (RR 2.70, p<0.001). Preoperative malnutrition independently predicted higher medical and surgical complication rates, revision risk, and mortality after pilon fracture ORIF. Routine nutritional assessment and optimization should be considered to improve outcomes, with prospective studies warranted to define effective perioperative dietary strategies. Level III Retrospective Comparative Cohort Study