MRI shows a high incidence of carpal fractures in children with posttraumatic radial-sided wrist tenderness

Background and purpose — The epidemiology and optimal diag- nostics of wrist injuries in children are not known. We describe fractures revealed by magnetic resonance imaging (MRI) in a prospective population of children and adolescents with posttrau- matic radial-sided wrist tenderness, and compare the diagnostic value of radiographs and computed tomography (CT) with that of MRI. Patients and methods — From 2004 to 2007, patients less than 18 years of age who presented at our emergency department were included in the study. 90 wrists in 89 patients underwent clini- cal, radiographic, and low-fi eld MRI investigation. If plain radio- graphs or MRI revealed a scaphoid fracture, a supplementary CT scan was performed. Sensitivity and specifi city of radiographs and CT for diagnosis of scaphoid fractures was calculated using MRI as the reference standard. Results — 74 fractures were diagnosed in 61 of 90 wrists using MRI; 48 wrists had a scaphoid fracture, 8 had a distal radius fracture, 7 had a capitate fracture, and 3 had a triquetrum frac- ture. The most common combination of fractures was scaphoid and capitate. The sensitivity of radiographs for visualization of scaphoid fractures was 54% and the specifi city was 100%. The sensitivity for other fractures was < 50%. The sensitivity of CT for visualization of scaphoid fractures was 96% and it was between 33% and 100% for other fractures. Interpretation — MRI showed a high incidence of fractures in children and adolescents with posttraumatic radial wrist tender- ness, and it led to the diagnosis of more fractures than plain radio- graphs and CT. A scaphoid fracture was the most common carpal injury, followed by fracture of the capitate.