[Intra-observer variability of measurement of posture with three-dimensional digitization]

A new system based on 3D digitization with magnetic fields has been developed by our research team. The focus of this study was to evaluate the intratester reproducibility of this technique of measurement. Twenty key morphological parameters were used twice to digitize the fourty five female subjects aged 7 to 23 years. The results of variance analysis (ANOVA) for repeated measures showed no statistically significant difference between the two series of measurements for the twenty angles studied. In 56% of the measurements, the difference of the means was less than 1 degree, the greatest being 1.82 degrees. These results confirm the reliability of this new technique of postural evaluation when the measurements are taken by the same tester. Therefore, 3D digitization with magnetic fields could be an interesting alternative to X-Rays for the evaluation of scoliosis.