Pelvic radiography in blunt trauma patients is routinely used in most trauma centers. The purpose of this review was to evaluate the ability of physical examination alone to detect pelvic fractures. Among patients with blunt trauma admitted to the University Hospital del Valle in Cali, Colombia, over a 3-month period, 608 adult patients, with hemodynamic stability, without spinal involvement, and with a Glasgow Coma Scale score greater than 10 were evaluated. All patients had physical examination, pelvic x-ray and adequate follow-up. Fifty-nine (9.7%) patients had pelvic fractures, with 57 of these fractures detected by physical findings. The remaining two patients had stable fractures that required no treatment. After careful analysis, we conclude that a negative physical examination following blunt trauma has a negative predictive value of 99% probability in excluding pelvic fracture, provided that the patient is not a child, is not in coma, is hemodynamically stable without evidence of blood loss, and has no spinal cord injury. A selective use of pelvic x-ray in patients with blunt trauma is a cost-effective policy.