Vertebral fracture assessment using the lateral scoutview of computed tomography in comparison with radiographs

Semiquantitative vertebral fracture assessment was compared between lateral computed tomography (CT) scoutviews and conventional thoracolumbar spinal radiographs. Vertebral levels T4-L4 were assessed by both techniques in a g roup of 56 women (mean age 60 +/- 13 years). In order to compare inter- and intraobserver variabilities for the two techniques, the images were analyz ed twice by two independent observers, and percentage agreement and kappa s tatistics were measured both between readings and between observers. Percen tage agreement and kappa statistics were also used to quantify differences between techniques. In the CT scoutviews, noise and artifacts from overlyin g tissues in the thoracic spinal levels rendered 3.4% of the vertebrae unre adable for the first observer and 8.3% for the second observer. For the CT scoutviews the agreement between readings was 98.1%, 97.3% and 100% (kappa = 0.87, 0.83 and 1.0) on T4-L12, T4-12 and L1-4, respectively for the first observer, and 97.8%, 97.1% and 99.5% (kappa = 0.79, 0.73 and 0.92) for the second observer. For the lateral radiographs, the agreement between readin gs was 97.7%, 96.9% and 100% (rc = 0.87, 0.85 and 1.0) on T4-L12, T4-12 and L1-4, respectively for the first observer, and 98.4%, 97.7% and 99.5% (kap pa = 0.86, 0.82 and 0.95) for the second observer. The agreement between ob servers was 96.1%, 94.4% and 100% (kappa = 0.68, 0.58 and 1.0) on T4- L12, T4-12 and L1-4, respectively for the CT scoutviews and 96.8%, 95.9% and 99. 0% (kappa = 0.79, 0.76 and 0.91) for the lateral radiographs. The inter-tec hnique was 95.8%, 94.2% and 99.5% (kappa = 0.73, 0.68 and 0.95) on T4-L12, T4-12 and L1-4, respectively for the first observer and 95.6%, 94.2% and 99 .0% (kappa = 0.64, 0.55 and 0.90) for the second observer, with the scoutvi ew technique detecting, on average, 23% fewer fractures than the lateral ra diographs. Although the vertebral fracture detection in lumbar spine is qui te comparable to that of conventional radiographs, given its reduced sensit ivity for vertebral fracture detection in thoracic spine, the lateral CT sc outview technique should not be substituted for conventional radiographs wh ere diagnosis of all vertebral fractures is of primary importance.