The effects of flexion and extension exercises on lumbar discs and low-back pain are controversial. Our goals were to develop a technique and program for digitizing and analyzing discograms and to study the motion of intradiscal dye in response to flexion and extension. Thirty-five patients following awake discography were evaluated with lateral radiographs obtained in an extension position and a flexion position. Fifty-three segments with normal morphology and 47 segments with abnormal morphology were studied. Discograms with normal morphology showed numerically significant change in position with a more anterior position occurring during extension. Changes in the position of intradiscal dye in discs with abnormal morphology were less predictable. Digitizing was an advantageous technique.