Research on Constitutive Laws of Lumbar Intervertebral Disc with Biphasic Thoery
Project/Area Number |
08458279
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Biomedical engineering/Biological material science
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Research Institution | HOKKAIDO UNVIERSITY |
Principal Investigator |
TADANO Shigeru Graduate School of Engineering, Hokkaido University, Associate Professor, 大学院・工学研究科, 助教授 (50175444)
|
Co-Investigator(Kenkyū-buntansha) |
ITOH Manabu Medical Hospital, Hokkaido University, Research Associate, 医学部, 助手 (00271677)
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Project Period (FY) |
1996 – 1998
|
Project Status |
Completed (Fiscal Year 1998)
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Budget Amount *help |
¥7,200,000 (Direct Cost: ¥7,200,000)
Fiscal Year 1998: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1997: ¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1996: ¥3,400,000 (Direct Cost: ¥3,400,000)
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Keywords | Lumbar Intervertebral Disc / Biphasic Theory / Consitutive Law / Visco-elastic Deformation / Intradiscal Pressure / Loading Response / 線維輪 / 異方性特性 / シミュレーション |
Research Abstract |
The aim of this research project is to develop the constitutive laws of lumbar intervertebral discs by applying the biphasic theory, and to simulate the visco-elastic deformation of the disc using the computational mechanics. The following results were obtained : (1) To analyze mechanically the visco-elastic deformation of the lumbar intervertebral disc, the constitutive equations were formulated from by the biphasic theory, and was developed a modeling method represented the mechanical behavior of inner tissues in the disc : nucleus pulposus, annulus fibrosus and the trangeint region between them. The computational analysis using the finite element method could simulate the creep deformation of the intervertebral disc taking time dependency into account. (2) The method to measure the intradiscal pressure response to low-frequency vibration loading was developed using a calf lumbar spinal segment which is two vertebral bodies and one intervertebral disc. The experiment was carried out in a physiological saline solution to simulate in vivo conditions. Prior to the vibration test, the equilibrium pressure was measured under the constant load during I hour. The amplitude and frequency were controlled after the intradiscal pressure reached the equilibrium. (3) The macroscopic constitutive law of the lumbar intervertebral disc to be described mathematically with the finite deformation theory. Mechanical behaviors of the cadaveric lumbar disc obtained from continuous cyclic compression-tension test and continuous cyclic axial torsion test were formulated by the constitutive equation with a semi-circular shaped model. These equations were taken with or without nucleus pulposus into account. It was also confirmed that forward-backward bending behavior of the disc could be simulated numerically from these equations.
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Report
(4 results)
Research Products
(16 results)