Diagnosis of scaphoid fracture and dedicated extremity MRI.

We evaluated the value of dedicated extremity magnetic resonance imaging (E-MRI) in patients with clinical suspicion of a scaphoid fracture and normal initial radiographs. 52 patients underwent E-MRI within a mean of 4 (2-10) days after trauma. Follow-up radiographs were performed at average 11 (8-14) weeks after trauma, and these images were used as the "gold standard". A T1-weighted turbo gradient echo 3D and a tau short inversion recovery STIR were performed, both in coronal planes. The imaging time was less than 10 min. The images were evaluated independently by two radiologists. E-MRI detected occult fractures of the scaphoid in 9 patients, and of the distal radius in a further 6 patients. All these fractures were confirmed at follow-up radiographs. Furthermore, E-MRI revealed a fracture of the capitate bone in 1 patient, and of the triquetrum in 2 patients, and in 8 patients, bone bruise in 1 or more of the carpal bones. However, these fractures and bone lesions could not be confirmed by the follow-up radiographs. The agreement between the two examiners was high (kappa = 0.8) for E-MRI detection of fractures. E-MRI seems to be better than radiographs in the early diagnosis of occult fractures of the scaphoid bone and the wrist.