Background The aim of this study was to determine whether a normal range of elbow movement can be used as a rule out tool for significant injury after blunt trauma in the paediatric population.

Methods A prospective observational study was set up in an Australian tertiary paediatric emergency department. Patients from 3 to 16 years old were included. Active range of elbow movement (flexion, extension, supination and pronation) was recorded as either normal or abnormal. All participants received standard elbow x-rays. Range of movement (ROM) was compared to the radiologist's final x-ray report. An x-ray was considered abnormal if it showed a fracture, dislocation or isolated elbow effusion.

Results 177 patients were included in the study, of which all received elbow x-rays. 146 had a restricted ROM (82%). 106 x-rays were reported as abnormal (60%). An abnormal ROM had a sensitivity of 93.4% (95% CI 86.9% to 97.3%), specificity 33.8% (95% CI 23.0% to 46.0%) and negative predictive value of 77.4% (95% CI 58.9% to 90.4%) for an abnormal x-ray. There were seven false-negative results in this group. Clinical management was changed in four of these patients due to abnormalities seen on x-ray.

Conclusion In the setting of blunt trauma resulting in elbow injury in children, a normal ROM does not rule out a significant injury and should not be used as a screening tool.