The results from this study suggest that there are several key factors involved in the initiation and propagation of anulus failure: axial compressive load, bending and twisting, and disc saturation. If one of these is lacking, anulus failure is harder to achieve.

Changes in viscous damping and myofilament activation in combination may cause pressure-hypertrophied cardiocytes to resist changes in shape during diastole and contribute to diastolic dysfunction.

Variations in disc height may compromise the general conclusions reached from experimental work and analytic studies in which geometric parameters (especially disc height and disc cross-sectional area) are not taken into consideration.

A viscoelastic finite element model of a L2-L3 motion segment was constructed and used to study: (1) the behavior of the intervertebral disc with different amounts of nucleus fluid loss; and (2) the effect of different rates of fluid loss on the viscoelastic behavior of the disc. The results indicate that: (1) The viscoelastic behavior of the intervertebral disc depends to a large extent on the rate of fluid loss from the disc; the intrinsic properties of disc tissue play a role only at the early stage of compressive loading; (2) the axial strain increases, whereas the intradiscal pressure and the posterior radial disc bulge decrease with increasing fluid loss; (3) a decreasing fluid loss rate with a total fluid loss of 10 to 20 percent (from the nucleus) during the first hour of compressive loading best predicts the overall viscoelastic behavior of a disc.