Quantifying magnification in pedal radiographs.

Morphometric comparison between metatarsals on pedal radiographs and preserved bone specimens provides a method to quantify the amount of magnification imparted on a radiographic image. Conversion factors are presented for dorsoplantar and lateral projection images, which are of value in the preoperative assessment of patients. Factors that influence radiographic quality are discussed, with an emphasis on the geometry of projecting an accurate image.