Forty Degree Angled Coronal CT Scanning of Scaphoid Fractures through Plaster and Fiberglass Casts

A method for obtaining coronal CT scans angled 40 degrees to the longitudinal axis of the wrist, parallel to the long axis of the scaphoid, is described. Its potential for evaluating scaphoid fractures is assessed in 10 patients with healing or clinically suspected fractures. Overlapping 3 mm thick angled coronal CT scans were obtained for each patient both in and out of cast. The CT images were compared to plain films and tomography. Comparisons were also made of CT images obtained through fiberglass and plaster casts. All fractures apparent by plain films and tomography were apparent by CT; one case suspected of fracture on initial plain films showed no evidence of fracture on CT and subsequent clinical course and plain films. Osseous union of healing fractures was more reliably assessed on CT than on plain films and plain film tomography. There was no degradation of CT images by either fiberglass or plaster casts; fiberglass casts allowed easy planning of tomographic slices from scout films. We conclude that direct 40 degree angled coronal CT examination of the scaphoid is a quick reliable method to detect scaphoid fractures and to assess their healing without the need of cast removal.