Reformatted magnetic resonance imaging scans of 27 normal wrists were examined in incremental degrees of rotation around the central axis of the radial shaft to 30° in both directions from true lateral. A line was superimposed on the outer border of the radial dorsal cortex and continued distally to the carpal region. Measurements were made from the superior pole of the lunate to this line. This distance did not change significantly with rotation. This allows a quick and accurate way of assessing distal radial fracture reduction from poorly taken lateral radiographs. In addition, the relevant landmarks are not obscured by implants or casts.

Level of evidence: III, diagnostic study