Spinal analysis using a three-dimensional radiographic technique.

Abstract This paper presents an in vivo clinical method for describing the three-dimensional configuration of spinal segments. The technique is based upon the characterization of each vertebral segment by four points in three-dimensional space using bi-plane roentgenography and subsequent analysis by computer aided descriptive geometry techniques. Tests were conducted to determine the system's accuracy and repeatability. The results of these tests using both a calibrated mechanical model of the spine and actual in vivo spine evaluations are presented.