Nutritional vulnerability predicts complications in patients with femoral shaft fractures

Malnutrition is common in orthopaedic trauma and may increase postoperative morbidity. This study evaluated the association between laboratory-defined malnutrition and 90-day medical complications and 2-year fracture-related complications after femoral shaft fracture fixation.

Using the TriNetX Research Network (112 healthcare organizations), adults (≥18 years) undergoing operative fixation of femoral shaft fractures were identified. Malnutrition was defined as albumin ≤ 3.5 g/dL and/or leukocytes ≤ 1.5× 10³ /µL measured within 1 year before the index procedure; patients without documented laboratory-defined malnutrition served as controls. Cohorts were propensity score-matched 1:1 on demographics, comorbidities, and selected laboratory measures. Complications were assessed from postoperative day 1 through 90 days (acute respiratory failure/mechanical ventilation, DVT/PE, transfusion, postoperative infection, wound disruption, myocardial infarction, sepsis, acute kidney injury, and emergency department visit) and through 730 days (nonunion/malunion, osteomyelitis, revision fixation, and hardware removal). Risk ratios (RR) with 95 % confidence intervals (CI) were reported.

After matching, 10,943 patients remained in each cohort with good covariate balance (all standardized mean differences <0.10). Within 90 days, malnutrition was associated with higher risk of acute respiratory failure/mechanical ventilation (21.7 % vs 9.5 %; RR 2.29 [95 % CI 2.14-2.45]), sepsis (6.1 % vs 2.9 %; RR 2.09 [1.84-2.39]), DVT/PE (9.7 % vs 5.8 %; RR 1.68 [1.53-1.85]), acute kidney injury (12.8 % vs 8.3 %; RR 1.55 [1.44-1.68]), postoperative infection (4.4 % vs 2.6 %; RR 1.68 [1.46-1.94]), wound disruption (3.1 % vs 1.9 %; RR 1.68 [1.42-2.00]), transfusion (10.9 % vs 8.5 %; RR 1.29 [1.19-1.40]), myocardial infarction (2.4 % vs 1.8 %; RR 1.30 [1.08-1.56]), and emergency department visit (16.4 % vs 14.3 %; RR 1.15 [1.08-1.23]) (all p ≤ 0.005). At 2 years, malnutrition was associated with higher risk of osteomyelitis (1.1 % vs 0.4 %; RR 2.43 [1.74-3.38]), revision fixation (5.9 % vs 4.0 %; RR 1.47 [1.31-1.66]), and hardware removal (9.3 % vs 8.1 %; RR 1.15 [1.06-1.26]) (all p ≤ 0.001), while nonunion/malunion did not differ (3.0 % vs 2.9 %; RR 1.06 [0.91-1.23]; p = 0.472).

Laboratory-defined malnutrition was independently associated with substantially increased 90-day morbidity and higher 2-year infectious and reoperative complications after femoral shaft fracture fixation. These findings support nutritional risk stratification and motivate prospective studies evaluating targeted perioperative optimization.