The appropriate use of contrast venography and pulmonary angiography in the orthopedic population.

Lower-extremity venous thrombosis and its major complication, pulmonary embolism, occur with an increased prevalence in the orthopedic population, even in patients receiving prophylactic therapy. Compression ultrasound has become the diagnostic test of choice to screen high-risk patients and to evaluate symptomatic patients. Contrast venography should be reserved to evaluate the few patients in whom adequate quality ultrasound examinations are unobtainable. Pulmonary angiography remains the "gold standard" in the diagnosis of pulmonary embolism and should be obtained in all patients in whom ventilation-perfusion scan results are discordant with clinical suspicion, and whenever treatment risks are extraordinary.