Comparative evaluation of postreduction intra-articular distal radial fractures by radiographs and multidetector computed tomography.

BACKGROUND: Computed tomography can be an adjunct to radiographs when evaluating intra-articular fractures of the distal part of the radius. Acute-phase multidetector computed tomography has better temporal, spatial, and contrast resolution than a conventional scanner has. The aim of this study was to determine prospectively whether the addition of a multidetector computed tomography scan (with various reconstructions) results in changes in the evaluation of intra-articular distal radial fractures and thus changes in the plans for further management.
METHODS: Radiographs and multidetector computed tomography scans were compared prospectively in the evaluation of 117 patients (120 wrists) with acute intra-articular distal radial fractures. The parameters that were measured included the ability to detect intra-articular step and gap displacements, central articular depression, coronal plane fracture, the number of articular fragments, comminution, and associated injuries in the wrist region (carpal bone fractures, distal radioulnar joint disruption, and ulnar styloid fracture).
RESULTS: The average measurements for intra-articular step and gap were 0.4 mm and 0.9 mm, respectively, on post-reduction radiographs and 1.3 mm and 2.4 mm, respectively, on sagittal multidetector computed tomography images (p < 0.0001 for each). Central articular depression was found in twenty-one wrists (18% of the total) on radiographs, but on multidetector computed tomography it was found to be present in seventy-four wrists (62% of the total) (p < 0.0001). Twenty-six radiographically occult injuries in the wrist region, including six scaphoid fractures, were detected with the help of multidetector computed tomography. Overall, the recommended treatment plan changed in 23% of the cases when the evaluation included multidetector computed tomography images in addition to conventional radiographs. Interobserver and intraobserver agreements were significantly increased when radiographs and multidetector computed tomography images both were available for evaluation (κ = 0.73 and 0.91, respectively) as compared with interobserver and intraobserver agreement with radiographs alone (κ = 0.43 and 0.69, respectively).
CONCLUSIONS: Multidetector computed tomography provides more accurate information regarding the anatomy of intra-articular distal radial fractures than radiography provides. The addition of multidetector computed tomography to plain films frequently changes the therapeutic recommendations for such cases.