Ultrasound in forearm fractures: a pragmatic study assessing the utility of Point of Care Ultrasound (PoCUS) in identifying and managing distal radius fractures.

Background: Point of Care Ultrasound (PoCUS) is a safe, non-invasive tool for identifying distal radius fractures and can potentially be utilised to assist clinicians to reduce displaced fractures. We aim to test whether PoCUS is accurate to identify distal radius fractures and to determine how PoCUS performs as a tool to confirm a successful fracture reduction.

Methods: A pragmatic prospective observational study was done in adult patients presenting with forearm injuries resulting in Colle's type distal radius fractures. Adults who presented to the emergency department (ED) with a suspected distal forearm fracture from August 2018 to July 2019 were conveniently sampled for inclusion into the study when a trained ED ultra-sonographer was available. PoCUS scans over the point of maximal tenderness were done using a high frequency linear transducer (7.5-10 mHz) prior to X-ray. Patients who required a manipulation of the fracture had a second ultrasound scan immediately after the procedure before the second X-ray was ordered. PoCUS scans were compared to X-rays for accuracy in both groups.

Results: Fractures were identified in 44 out of 47 included patients using both PoCUS and X-ray modalities. This showed a sensitivity of 100% (95% CI: 90-100%) and specificity of 100% (95% CI: 31-100%). Fracture manipulation was required in 35 out of 44 patients. The sensitivity and specificity of PoCUS in determining alignment accuracy when compared to X-ray were 100% (95% CI: 83-100%) and 64% (95% CI: 32-88%) respectively. The PPV and NPV were 86% (95% CI: 66-95%) and 100% (95% CI: 56-100%) respectively. Ten out of 44 (23%) patients with distal radius fractures ultimately required an Open Reduction and Internal Fixation (ORIF).

Conclusion: Our study supports the use of PoCUS for identifying distal radius forearm fractures and may have some value in assisting clinicians to determine post reduction success. We still advocate using standard X-ray radiographs to confirm successful or adequate cortical alignment following a manipulation.