Interobserver variability among radiologists for diagnosis of scaphoid fractures by computed tomography

To determine the interobserver variability among radiologists for computed tomography (CT) diagnosis of scaphoid fractures.

Four specialized musculoskeletal radiologists evaluated the CT scans of 150 consecutive patients who were clinically suspected of having sustained a scaphoid fracture but whose scaphoid-specific radiographs were normal. The radiologists were asked to determine the presence or absence of a scaphoid fracture and to localize the fracture. Interobserver agreement was calculated using the kappa statistic.

The radiologists diagnosed between 11 (7%) and 22 (15%) scaphoid fractures; the kappa value was 0.51.

Agreement on the presence of a scaphoid fracture and its location on a CT scan was moderate among the 4 radiologists. This finding raises the question as to whether scaphoid fractures could be under- or overdiagnosed in daily practice when CT is used to exclude or confirm a fracture. This should be kept in mind when interpreting clinical and radiological results in patients with suspected scaphoid fractures.