Meta-analysis of Randomized Trials in Emergency and Acute Orthopedic Trauma Comparing Aspirin and Low-Molecular-Weight Heparin for Thromboprophylaxis
Abdulelah F. Alshehri, Waleed O. Samarkandi, Leena Muhanad, Hassan E. Mesri, Omar H. Bin Salleeh, Ahmad M. AlAmiri, Abdullah A. Bukhari, Abdulrahman M. Alshehri, Abdullah A. Alrajeh, Faris A. Alrazoq, Abdulrahman A. Alshawaf, Ahmad A. Alzamel, Mohammed M. Alsheikh Tahboub, Mohammed I. Albadawi, Salman S. AlqahtaniBackground
Venous thromboembolism remains an important complication after acute orthopedic trauma. Low molecular weight heparin has historically been the conventional pharmacologic standard for thromboprophylaxis, while aspirin has gained increasing clinical interest as a practical alternative. This systematic review and meta-analysis evaluated randomized controlled trial evidence comparing aspirin with low molecular weight heparin after acute orthopedic trauma.
Methods
PubMed, Scopus, and Web of Science were systematically searched from database inception through March 21, 2026. Randomized controlled trials comparing aspirin with low molecular weight heparin in adults with acute orthopedic trauma requiring thromboprophylaxis were included. Primary outcomes were all cause mortality, bleeding complications, and infection related complications. Quantitative synthesis was performed where appropriate using pooled risk ratios with 95% confidence intervals under a random effects model. Venous thromboembolic outcomes were synthesized qualitatively because of heterogeneous endpoint definitions.
Results
Four publications representing two independent randomized orthopedic trauma trial programs involving 12,540 participants were included. Meta analysis showed no statistically significant differences between aspirin and low molecular weight heparin for all cause mortality (risk ratio 1.02, 95% confidence interval 0.69 to 1.53), bleeding complications (risk ratio 0.96, 95% confidence interval 0.88 to 1.05), or infection related complications (risk ratio 1.05, 95% confidence interval 0.80 to 1.37). No statistical heterogeneity was observed across pooled outcomes.
Conclusion
Aspirin did not demonstrate statistically significant differences from low molecular weight heparin in mortality or major safety outcomes within the currently available randomized orthopedic trauma evidence. However, comparative venous thromboembolic efficacy remains uncertain because thromboembolic outcomes could not be validly pooled. Further trauma specific randomized studies with standardized outcome reporting are needed.