Clinical Utilisation of Computed Tomography of the Scaphoid.

Computed tomography is the best imaging modality to assess bony architecture. Scanning in the longitudinal plane of the scaphoid provides a greater appreciation of the humpback deformity. CT scan provides superior assessment of union and has a higher correlation with operative findings. A limitation of CT scanning is partial volume averaging which may give a false impression of a partial union when a nonunion exists. Height-to-length ratio provides superior observer variability for the assesssment of the humpback deformity. CT is useful to be able to "template" the proposed surgery of the scaphoid. It allows the surgeon to determine whether a structural bone graft is required, the preferred screw fixation and whether a volar or dorsal approach is required.