Musculoskeletal injuries in a resource-constrained environment: comparing diagnostic accuracy of on-the-spot ultrasonography and conventional radiography for bone fracture screening during the Paris-Dakar rally raid

Background: Ultrasound (US) is a good first-line alternative for the diagnosis of bone fractures in adults as well as children. Our study shows that, compared to X-ray, in a resource-constrained environment, on-site US has a high sensitivity (98%) and specificity (96%) in the diagnosis of bone fractures. Purpose: To compare the accuracy of on-the-spot US with conventional radiography in the screening for bone fractures during the Paris-Dakar rally raid. Material and Methods: Eighty-three patients (81 men, 2 women) with clinically suspected bone fractures were included in 2013 and 2014. They underwent X-ray and US on the spot, blindly interpreted by two musculoskeletal radiologists. Using X-ray as gold standard, we calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for US, for each anatomic location. The accuracy of US and radiography were also assessed, as were the number of fragments and their degree of displacement (Student's t-test). Results: Compared with X-ray, sensitivity, specificity, PPV, and NPV of on-site US were, respectively, for the presence (or absence) of fractures: 98%, 98%, 100%, and 95%. The accuracy of US was 99%. Only one radial styloid process fracture was misdiagnosed with US. There was no significant difference between US and X-ray (P > 0.93) concerning the number of fragments and their degree of displacement. Conclusion: Bedside musculoskeletal ultrasound performed by trained musculoskeletal radiologists is a useful method in determining and assessing bone fractures in a resource constrained environment.