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. 2012;20(1):17-20.
doi: 10.1590/S1413-78522012000100003.

Photoelastic analisys in the lower region of vertebral body L4

Sarah Fakher Fakhouri  1 , Ariane Zamarioli  1 , Marcos Massao Shimano  2 , Helton Luiz Aparecido Defino  1 , Cleudmar Amaral Araujo  3 , Antonio Carlos Shimano  1
Affiliations

Photoelastic analisys in the lower region of vertebral body L4

Sarah Fakher Fakhouri et al. Acta Ortop Bras. 2012.

Abstract

Objective: To analyze the shear forces on the vertebral body L4 when submitted to a compression force by means of transmission photoelasticity.

Methods: Twelve photoelastic models were divided into three groups, with four models per group, according to the positioning of the sagittal section vertebrae L4-L5 (sections A, B and C). The simulation was performed using a 15N compression force, and the fringe orders were evaluated in the vertebral body L4 by the Tardy compensation method.

Results: Photoelastic analysis showed, in general, a homogeneous distribution in the vertebral bodies. The shear forces were higher in section C than B, and higher in B than A.

Conclusion: The posterior area of L4, mainly in section C, showed higher shear concentrations, corresponding to a more susceptible area for bone fracture and spondylolisthesis. Economic and Decision Analyses - Development of an Economic or Decision Model. Level I.

Keywords: Biomechanics; Spine; Tension.

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Conflict of interest statement

All the authors declare that there is no potential conflict of interest referring to this article.

Figures

Figure 1
Figure 1
Diagram of the three unilateral sagittal sections (A, B and C) created in vertebral body L4 to obtain the geometries of the photoelastic models. I- Location of the sagittal sections (A, B and C) in vertebral body L4. II– Geometry of sections A, B and C. III– Photoelastic models of sections A, B and C.
Figure 2
Figure 2
Diagram of a polytetrafluorethylene (Teflon®) mold with the disc made of T-208 resin, positioned in the center of the mold.
Figure 3
Figure 3
Diagram of the points selected for analysis of the shear forces in the three vertebral sections.
Figure 4
Figure 4
Distribution of shears in sections A, B and C. In section A, the shear concentration was higher in the anterior and posterior regions of the vertebra (arrows). In sections B and C, the shear concentration was higher in the posterior region (arrows).
See this image and copyright information in PMC

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References

    1. Prakash, Prabhu LV, Saralaya VV, Pai MM, Ranade AV, Singh G, et al. Vertebral body integrity: a review of various anatomical factors involved in the lumbar region. Osteoporos Int. 2007;18:891–903. - PubMed
    1. Fyhrie DP, Hoshaw SJ, Hamid MS, Hou FJ. Shear stress distribution in the trabeculae of human vertebral bone. Ann Biomed Eng. 2000;28:1194–9. - PubMed
    1. Yeni YN, Hou FJ, Vashishth D, Fyhrie DP. Trabecular shear stress in human vertebral cancellous bone: intra- and inter-individual variations. J Biomech. 2001;34:1341–6. - PubMed
    1. Yeni YN, Kim DG, Divine GW, Johnson EM, Cody DD. Human cancellous bone from T12-L1 vertebrae has unique microstructural and trabecular shear stress properties. Bone. 2009;44:130–6. - PMC - PubMed
    1. Lochmüller EM, Pöschl K, Würstlin L, Matsuura M, Müller R, Link TM, et al. Does thoracic or lumbar spine bone architecture predict vertebral failure strength more accurately than density? Osteoporos Int. 2008;19:537–45. - PubMed

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