A new method to measure vertebral rotation from CT scans

CT measurement methods have good reliability for idiopathic scoliosis trans verse plane deformity evaluation. However, because of application difficult ies and variations in how these methods are applied, more sensitive methods are needed. This paper presents a new method for measurement of vertebral rotation from tomographic scans. First, the method was subject to clinical, intraobserver and inter-observer analysis. Twenty-three patients with adol escent idiopathic scoliosis were studied to test the clinical reliability o f this method. There were no statistical differences between the results of the new method and Ho's method (P = 0.3380) in the clinical study. Intra-o bserver and inter-observer analysis showed that this method was reliable. A n experimental study was then conducted to show the confidence limits of ou r new method, which were found to be +/- 1.6 degrees, and there was no sign ificant difference between the mean rotation value obtained from CT scans u sing our new method and that obtained using the mechanical method. These re sults suggest that our new method is a simple, practical and reliable metho d for measurement of vertebral rotation from CT scans.