multiaxial loading | Force and Motion

multiaxial loading

Multigenerational growth approach to incorporate residual stress in an intervertebral disc finite element model with validation in multi-axial loading

Residual stresses are known to exist in human intervertebral discs but have not been incorporated in finite element models. A multigeneration model was applied to the annulus fibrosus of the intervertebral disc to simulate residual stresses arising from growth and remodeling. The intervertebral disc shape and compressive creep were used to verify that the multigeneration approach generates realistic values of residual stress. The model was then validated by comparing its 6 degree-of-freedom mechanical response to experimental data. Human intervertebral discs were tested in a custom-built hexapod in all 6 degrees-of-freedom (lateral shear, anterior-posterior shear, torsion, bending, flexion, and compression). Incorporating residual stresses resulted in a finite element model which can predict 4 degrees-of-freedom while excluding residual stresses produces a finite element model that can only predict 2 degrees-of-freedom.
Listed In: Biomechanical Engineering, Biomechanics, Orthopedic Research