Email updates

Keep up to date with the latest news and content from Scoliosis and BioMed Central.

Open Access Research

The three-dimensional easy morphological (3-DEMO) classification of scoliosis – Part III, correlation with clinical classification and parameters

Stefano Negrini* and Alberto Negrini

Author Affiliations

ISICO (Italian Scientific Spine Institute), Milan and Fondazione Don Carlo Gnocchi IRCCS-ONLUS, Milan, Italy

For all author emails, please log on.

Scoliosis 2007, 2:5  doi:10.1186/1748-7161-2-5

Published: 19 March 2007

Abstract

Background

In the first part of this study we proposed a new classification approach for spinal deformities (3-DEMO classification). To be valid, a classification needs to describe adequately the phenomenon considered (construct validity): a way to verify this issue is comparison with already existing classifications (concurrent and criterion validity).

Aim

To compare the 3-DEMO classification and the numerical results of its classificatory parameters with the existing clinical classifications and the Cobb degrees on the frontal and sagittal planes respectively.

Methods

118 subjects (96 females) with adolescent idiopathic scoliosis (age 15.9 ± 3.1, 37.4 ± 12.5° Cobb) have been classified according to 3-DEMO, SRS-Ponseti, King and Lenke classifications as well as according to sagittal configuration. For all patients we computed the values of the 3-DEMO parameters and the classical Cobb degrees measurements in the frontal and sagittal planes. Statistical analysis comprised Chi Square and Regression analysis, including a multivariate stepwise regression.

Results

Three of the four 3-DEMO parameters (Direction, Sagittal and Frontal Shift) correlated with SRS-Ponseti, King and sagittal configuration classifications, but not with Lenke's one. Feeble correlations have been found among numerical parameters, while the stepwise regression allowed us to develop almost satisfactory models to obtain 3-DEMO parameters from classical Cobb degrees measurements.

Discussion

These results support the hypothesis of a possible clinical significance of the 3-DEMO classification, even if follow-up studies are needed to better understand these possible correlations and ultimately the classification usefulness. The most interesting 3D parameters appear to be Direction and mainly Phase, the latter being not at all correlated with currently existing classifications. Nevertheless, Shift cannot be easily appreciated on classical frontal and sagittal radiographs, even if it could presumably be calculated.