ISSN:
0736-0266
Keywords:
Viscoelasticity
;
Creep analysis
;
Lumbar motion segment
;
Compression
;
Disc degeneration
;
Aging
;
Life and Medical Sciences
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Medicine
Notes:
The in vitro viscoelastic “creep” behavior was examined in 18 cadaveric human lumbar motion segments subjected to static axial compressive loads. Axial deformation was followed for 30 min under constant applied load. Compressive material constants (moduli and viscosity coefficients) were then determined for each intervertebral disc using a linerization method based on a Taylor series expansion of experimental data for the “three parameter” viscoelastic creep model. The degree of disc degeneration and bone mineral content (BMC) were also assessed. Good correlation between the experimentally determined and model predicted strain values were found, with the average error 〈1%. We found that motion segments from older and more degenerated lumbar discs were less stable and had lower material constants than segments from younger and less degenerated discs. Material constants and BMC correlated closely, suggesting that an interdependency of disc and vertebral body properties exists. No correlation between the creep characteristics and disc height, disc area, segment level, or sex were noted.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jor.1100050402
Permalink
