A CT-based approach with 3D modeling to determine optimal radiographic views of the scaphotrapezial and scaphotrapezoid joints.

Overview

PURPOSE: To use a CT-based approach with 3D modeling to determine novel radiographic views of the scaphotrapezial (STl) and scaphotrapezoid (STd) joints. MATERIALS AND METHODS: Consecutive wrist CT scans excluding those with pathology of the distal radius, scaphoid, trapezium, or trapezoid of subjects between ages 18 and 60 years were retrospectively reviewed. Three-dimensional reconstructions of CT scans were created and best-fit planes of the STl and STd joints were generated. Angles of these planes relative to a distal radial coordinate system were calculated to determine tilt of the wrist and the X-ray beam for novel radiographic views of these joints. RESULTS: Fifty eligible wrist CT scans were identified. The mean age was 38 years (range, 18 to 59). For the novel STl PA view, the wrist is supinated 17° from the standard PA view and the X-ray beam is canted 6° caudad. In the STl lateral view, the wrist is pronated 17° from the standard lateral view, and the X-ray beam is canted 20° caudad. In the STd PA tilt view, the wrist is supinated 28° from the standard PA view, and the X-ray beam is canted 13° caudad. In the STd joint lateral tilt view, the wrist is pronated 28° from the standard lateral view, and the X-ray beam is canted 29° caudad. CONCLUSION: We describe novel radiographic views of the STl and STd joints based on 3D modeling of wrist CT scans. Further studies are required to assess the efficacy of these views in detecting joint pathology.