Sensitivity of various material properties to the intervertebral disc biomechanics

This study aims to conduct a parameter sensitivity analysis to identify the most influential material properties governing intervertebral disc creep behavior. The 12 key material properties include water contents (ϕw), fixed charge densities (cf), and mechanical properties (μ, λ, k1)) across the nucleus pulposus, annulus fibrosus, and cartilaginous endplate. Finite element simulations of creep tests were validated against experimental bounds. Of 600 simulations, 58 fell within experimental bounds (R2 > 0.8). Water content was the most influential parameter across all creep response variables, followed by fiber reinforcement and fixed charge density. Our findings are important for understanding disc biomechanics.