Spinal rotation meter: development and comparison of a new device.

Quantification of the bending test became necessary within a large school screening for scoliosis, which started in 1983 in the central part of the Netherlands. Measurement of the angle of trunk rotation appeared to be the easiest method for the school doctors involved. Since at that time no device was commercially available, a device was developed to permit an easy and reliable angle measurement. Methodological qualities of the device in the measurement of the Cobb angle on radiographs are reported. The results of interobserver variation in measurement of the angle of trunk rotation and in the determination of the Cobb angle on radiographs using this device are compared with data from other studies reported in the literature. We did not find important differences in interobserver variation. Measurements of the Cobb angle with the new device could not be distinguished from the Cobb angle determination using conventional techniques. Therefore, we conclude that the spinal rotation meter described here is a reliable device for the measurement of scoliosis parameters.