Twice-daily low-dose aspirin is similar to enoxaparin for thromboprophylaxis after inpatient treatment for fracture (PREVENT CLOT)

Clinical Question

Is twice-daily low-dose aspirin noninferior to a low-molecular-weight heparin for thromboprophylaxis after an extremity, acetabular, or pelvic fracture?

Bottom line

Aspirin is noninferior to enoxaparin for thromboprophylaxis following inpatient treatment of a fracture. It is, of course, much cheaper, more convenient, and preferred by patients. The challenge will be convincing orthopedic surgeons that, in this case, "less is more." 1b

Study design: Randomized controlled trial (single-blinded)

Funding: Government

Setting: Inpatient (any location)


Mark H. Ebell, MD, MS
University of Georgia
Athens, GA

Discuss this POEM



Impact assessment

Very good

Pieter Richard Verbeek

Low dose aspirin vs LMWH post fracture treatment

Interesting statement by reviewer regarding the challenge in convincing surgeons to change their practice. I think this could be exacerbated by the observation of the "number needed to harm = 125" when using ASA instead of LMWH. One wonders if any surgeon would be will to take this risk.


post fracture dvt

asa bid cheaper,easier


ASA as effective as enoxaparin

Good to know. Much cheaper!