Abstract
BACKGROUND: Laboratory nutritional-risk markers have been associated with complications in orthopaedics, yet their influence after humeral shaft fracture management is underexplored. This study compared 90-day and 2-year complications after operative humeral shaft fracture treatment in patients with laboratory-defined nutritional-risk marker positivity versus marker-negative controls. METHODS: This retrospective cohort study used electronic medical records from the TriNetX network. Patients undergoing operative humeral shaft fracture treatment were stratified by laboratory-defined nutritional-risk marker positivity (serum albumin ≤3.5 g/dL and/or leukocyte count ≤1.5 × 10(3)/μL [severe leukopenia] within 1 year before surgery) or no marker positivity. Cohorts were propensity score matched to account for baseline differences. RESULTS: For the 90-day analysis, 6817 marker-positive and 37,857 marker-negative patients were identified, with 6687 per cohort after matching. Laboratory-defined nutritional-risk marker positivity was associated with higher 90-day risks of acute respiratory failure/mechanical ventilation (RR: 2.95; 95% CI: 2.61-3.34), venous thromboembolism (RR: 2.64; 95% CI: 2.20-3.15), blood transfusion (RR: 2.69; 95% CI: 2.18-3.31), postoperative infection (RR: 2.00; 95% CI: 1.61-2.49), wound disruption (RR: 2.36; 95% CI: 1.82-3.08), sepsis (RR: 4.05; 95% CI: 3.24-5.07), acute kidney injury (RR: 2.24; 95% CI: 1.95-2.56), and emergency department utilization (RR: 1.40; 95% CI: 1.30-1.50) (all p < 0.001). For the 2-year analysis, 7052 marker-positive and 39,137 marker-negative patients were identified, with 6919 per cohort after matching. Laboratory-defined nutritional-risk marker positivity remained associated with higher infection (RR: 1.69; 95% CI: 1.44-1.99), hardware removal (RR: 1.61; 95% CI: 1.42-1.81), osteomyelitis (RR: 2.55; 95% CI: 1.52-4.27), and bone grafting (RR: 1.84; 95% CI: 1.06-3.22. CONCLUSIONS: Laboratory-defined nutritional-risk marker positivity was associated with early complications after humeral shaft fracture surgery and increased infection-related and hardware-related morbidity within 2 years. These findings support use of laboratory markers for risk stratification and perioperative management.