PREVENTion of Clot in Orthopaedic Trauma: A Randomized Pragmatic Trial Comparing the Complications and Safety of Blood Clot Prevention Medicines Used in Orthopaedic Trauma Patients

Principal Investigator: Bellal Joseph, MD                 

Funding Source: Patient Centered Outcomes Research Institute (PCORI)

Start Date: November 2017 – December 2021

Enrolling: 12,200 patients across the country

More Information:

Each year, in the United States alone, blood clots are estimated to affect 300,000 – 600,000 patients.1 Even minor blood clots require a minimum of 6 months of medication, often with frequent blood tests and increased risk of medication-related bleeding. At their most severe, PEs are thought to account for 60,000–100,000 deaths per year in the United States.2 Patients who sustain trauma are well known to be at an increased risk for blood clots throughout their body, including fatal PE’s.3 Despite the common nature of these injuries and the potentially devastating impact that blood clots can have on patients’ lives, we currently do not know the best prophylactic regimen for these patients. A recent study on this topic by the Orthopaedic Trauma Association Evidence Based Quality Value and Safety Committee highlighted a knowledge gap surrounding clot prevention in orthopaedic trauma patients and concluded that there is “wide variability in practice patterns, poor scientific support for various therapeutic regimens” and that guidelines are needed to “improve patient care.”4

Purpose: The purpose of this research study is to see what medicine is better to use for preventing death and clinically important blood clots in the lungs in patients who sustain trauma.  There are two types of medicine we will compare in this study: Low Molecular Weight Heparin (LMWH) (Enoxaparin) and Aspirin.

For questions about this study, please contact Andrea Seach at 520-626-2876 or

1. Beckman MG, Hooper WC, Critchley SE, Ortel TL. Venous thromboembolism: A public health concern. Am J Prev Med. 2010;38(4 Suppl):S495-501.

2. Center for Disease Control and Prevention. Venous throboembolism (blood clots). Updated 2015. Accessed 02/11, 2016.

3. Barrera LM, Perel P, Ker K, Cirocchi R, Farinella E, Morales Uribe CH. Thromboprophylaxis for trauma patients. Cochrane Database Syst Rev. 2013;(3):CD008303. doi(3):CD008303.

4. Sagi HC, Ahn J, Ciesla D, et al. Venous thromboembolism prophylaxis in orthopaedic trauma patients: A survey of OTA member practice patterns and OTA expert panel recommendations. J Orthop Trauma. 2015;29(10):e355-62.