QUANTITATION OF INCIDENT SPINAL FRACTURES - COMPARISON OF VISUAL DETECTION WITH QUANTITATIVE MORPHOMETRY

The value of quantitative morphometry in detection of new spinal fract ures was assessed in serial radiographs from 83 patients with osteopor osis, From vertebral landmarks on lateral spine radiographs, a compute r program allowed calculation of vertebral heights and area, By compar ing vertebral dimensions in the two sets of films, incident spinal fra ctures could be quantitated based either on the minimum criteria of 15 % reduction in vertebral height (CM2) or a fall in height and area of 20% and 10% (CM1). The results of quantitative morphometry were compar ed with those of the consensus and individual readings of visual detec tion by three experienced investigators in the same paired sets of spi nal films, For incident new fractures, the visual consensus method (VC ) showed a very good agreement with individual visual detection (kappa of 0.794 to 0.916) as well as with CM1 (kappa of 0.821), However, the re was a poor agreement between the results of consensus reading and o f detection by CM2 (kappa of 0.341), due to excessive number of fractu res identified by CM2, but not by the visual method, For incident recu rrent fractures, there was a poor agreement between V-C and individual visual detection, and between V-C and quantitative morphometry (kappa of 0.306 to 0.496), It was due to severe compression fractures at bas eline, which caused further changes in vertebral dimensions difficult to measure accurately by either visual or quantitative morphometry, Th us, if the visual detection of fractures by a consensus of experienced investigators is considered as the ''gold standard,'' quantitative mo rphometry, based on minimum reduction in vertebral height of 20% accom panied by a minimum decline in area of 10%, provides an objective dete ction of incident new spinal fractures but not of recurrent fractures.