Can the spinal curvature irregularity index (SCII) also predict vertebral fractures in Italian women

Detection and diagnosis of vertebral fractures (VFs) are very important in all stages of osteoporosis. Radiographs or DXA vertebral fracture assessment (VFA) images of thoracolumbar spine are therefore an important tool in the clinical evaluation of osteoporosis. However, diagnosing VFs still can be difficult. There is often no clear distinction between a structural failure and the normal anatomic variation in anterior, middle and posterior height of the vertebrae. The aim of this multicentric study is to determine if the SCII can also identify vertebral deformities in Italian women. The SCII is the integrated average of the vertebral heights (VHs) over the thoracolumbar spine to give a quantitative estimate of the regularity of the spinal curvature (Zebaze et. al. (2004): JBMR, 19; 1099-1104). A large SCII is presumed to correlate with the presence of vertebral deformities. The study was performed with 569 Italian women, aged 28-89 yrs. from 4 different Italian centra. VHs were obtained from VFA (Lunar Prodigy, GE Healthcare). ROC analysis and logistic regression was performed using Minitab. SCII was transformed to ln (SCII) for normality. T-test was used to compare average transformed SCII. 40 women out of the 569 studied subjects had a vertebral deformity. The average SCII was significantly higher for subjects with one or more deformities: 13,40% compared to those without deformities 4,34% (p < 0,001). SCII increases significantly with increasing numbers of vertebral deformities. We conclude that the Spinal Curvature Irregularity Index clearly distinguishes between subjects with and without vertebral deformities also in an Italian population.