A biplane radiographic method of determining vertebral rotation in postmortem specimens.

Vertebral axial rotation can be measured by accurate identification of three bony landmarks: the tips of the superior articular facets; the inferior bases of the pedicles; the tips of the inferior articular facets. Geometric solution for the movement of these three points in space does not require an initial unrotated view, and can be proved with accuracy of up to 4 degrees in the thoracic spine and 3 degrees in the lumbar spine under experimental conditions. The method is applicable to the problem of measurement of structural scoliotic deformities on routine clinical roentgenograms.