Quantitative morphometric study of thoracic spine A preliminary parameters statistical analysis

Abstract

Study Design:A quantitative morphometric study of the thoracic spine from TI to T12 was conducted on 5o dried spines. Objective:To quantify anatomic descriptive parameters concerning thoracic vertebrae, and to investigate statistical correlation between some of them, in order to 1) refine knowledge of some dimensions and orientations for clinical applications z) aid for implant's designing, and, 3) improve existing geometric and mechanical models or 3D reconstruction techniques concerning thoracic spine. Summary of Background Data: A few three-dimensional quantitative studies were performed, either on a limited number of parameters, or on a limited series of specimens. No investigation of statistical correlation between parameters was previously performed concerning thoracic vertebrae. Methods: 373 thoracic vertebrae from 5o dried spines were considered. Three spatial coordinates of 14o points spread on the surface for each vertebrae (13o for Tlo, 12o for T11 and T12) were measured using an electromagnetic system (FASTRAK 9 estimated accuracy: + o.4 mm).Descriptive parameters were then calculated using Excel| and statistical correlation was investigated using xlSTAT| Results: The mean values and standard deviations of 81 linear, angular and surfacic parameters were obtained for the thoracic vertebrae on each level. High correlation was found for some parameters, such as interarticularis facet position, pedicles height and width, with the dimensions of the vertebral bodies that can be measured on X-rays. Conclusion: A detailed and accurate quantitative description of thoracic vertebrae is provided. For the first time, statistical correlation is demonstrated between some descriptive parameters which are visible on X-rays, and others which are not.