A computerized technique for vertebral morphometry

A new technique for morphometric measurement of vertebral bodies has been described, in which a computerized image analysis system was used to digitize and measure standardized lateral radiographs of the thoracic and lumbar spine. The sources of error in the radiographic system and the image analysis system were assessed using vertebral phantoms and test images. Oblique projection in the radiographic image of a vertebra did not produce a significant error in the measured area. The radiographic magnification was approximately 35%. Optical non-uniformity was detected in the image analysis system, and was ascribed to the lens optics. The maximum intra-observer and inter-observer variations in vertebral area were 3.1% and 5.3% respectively for experienced observers. The technique is applicable to clinical studies of large populations, and has value in investigating vertebral deformity in the management of metabolic bone disease.