Incidence of Incidental Musculoskeletal Injury on Lower Extremity Doppler Ultrasound in the Emergency Versus...

To determine the proportion of cases of lower extremity symptoms attributable to underlying musculoskeletal (MSK) rather than thrombotic etiologies in emergency versus non-emergency settings.

We retrospectively reviewed all lower extremity Venous Doppler ultrasounds performed on emergency department (ED) and non-ED patients over a 1-year period at a single institution. Using radiology report data mining software, keywords including tear, tendon, hematoma, and muscle were used to identify cases of MSK pathology of the lower leg. All reports were also reviewed for findings of venous thrombosis. Statistical significance between ED and non-ED patients for both incidental MSK pathology and venous thrombosis was assessed using chi-squared tests.

A total of 5714 lower extremity Doppler ultrasounds were performed at a single institution during the 1-year period, 1829 in the ED and 3885 in non-ED settings. Sixty-nine of 1829 (3.8%) ED patients had incidental MSK pathology of the lower extremity compared to 53/3885 (1.4%) in the non-ED setting (p < .001). Two hundred sixty-seven of 1829 (14.5%) ED patients had evidence of venous thrombosis and/or chronic post-thrombotic change. When combined with thrombotic pathology as positive cases, incidental MSK injury accounted for 69/336 (20.5%) of ED cases with positive sonographic findings.

MSK pathology of the lower leg is significantly more likely to contribute to lower extremity symptoms in the ED compared to a non-ED setting. Therefore, a brief sonographic evaluation of the MSK apparatus may be beneficial in a subset of ED patients, particularly those with focal pain but no identifiable thrombotic etiology.