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Updated: Feb 14, 2026

Cell-based Assay Protocol for the Prognostic Prediction of Idiopathic Scoliosis Using Cellular Dielectric Spectroscopy
Published on: October 16, 2013
Torsion bottle, a very simple, reliable, and cheap tool for a basic scoliosis screening
Michele Romano1, Matteo Mastrantonio1
1ISICO (Italian Scientific Spine Institute), Via Bellarmino 13/1, Milan, Italy.
Background:
One of the reasons that make scoliosis a disease that scares so much the parents is its specific characteristic of being difficult to detect on its onset.The aim of this paper is to check the possible usefulness of a simple tool (the torsion bottle) that has been developed with the aim to offer an instrument for home use by parents but also for screening purposes in the low-income countries.
Methods:
Study design: retrospective analysis to evaluate intra-operator reliability of the tools and inter-operator repeatability using the torsion bottle.For the first and the second part of the study, 35 subjects were measured.The goal of the first experiment was to evaluate the reliability of the torsion bottle to identify all individuals who experienced a thoracic or lumbar prominence equal or greater than 7°.The secondary aim was to verify the reliability of blinded inter-operator assessments, performed with the torsion bottle by two physiotherapists on the same patients.
Results:
The reliability of the assessments of the torsion bottle has been performed with the Kappa statistic to evaluate the measurement agreement.The results have shown that the intra-operator reliability of the tool is very high between the measurements collected with the scoliometer® and those collected with the torsion bottle (kappa = 0.9278; standard error = 0.7094).The data of the second part of the study show that the inter-operator reliability is good (kappa = 0.7988; standard error 0.1368).
Conclusion:
The collected data showed that the torsion bottle revealed itself as an efficient tool to execute a basic screening to identify the presence of a prominence in a significant group of adolescents.
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