The usefulness of computed tomography following open reduction and internal fixation of acetabular fractures.

PURPOSE To investigate the role of a supplemental imaging modality in postoperative assessment of acetabular fractures following open reduction and internal fixation. METHODS Postoperative axial computed tomographic (CT) scans were compared with plain radiographs of 20 patients with regard to their sensitivity for detecting articular fracture reduction in terms of gap displacement and step deformity or offset. Three observers independently reviewed the plain radiographs and CT scans at 2 separate time points and categorised the outcome as either anatomical or non-anatomical. The inter-observer reliability and intra-observer reproducibility of these measurements was expressed as a kappa statistic. The radiological result was correlated with the clinical outcome measures using the Merle D'Aubigne scale, the Harris Hip Score, and the SF-36 score. RESULTS Plain radiography was less effective in the detection of postoperative articular displacement (mean, 75.1% sensitive). The inter-observer and intra-observer agreement between reviewers was good to excellent in detecting reduction quality between the 2 modalities. Patient management was not altered by the findings of the CT scans. CONCLUSIONS Although postoperative CT scanning of acetabular fractures in selective cases may be useful, issues such as higher cost, less effective allocation of resources, and excessive radiation doses do not support its routine use.