Influence of spinal disc translational stiffness on the lumbar spinal loads, ligament forces and trunk muscle forces during upper body inclination

摘要

Inverse dynamic musculoskeletal human body models are commonly used to predict the spinal loads and trunk muscle forces. These models include rigid body segments, mechanical joints, active and passive structural components such as muscles, tendons and ligaments. Several studies used simple definition of lumbar spinal discs idealized as spherical joints with infinite translational stiffness. The aim of the current sensitivity study was to investigate the influence of disc translational stiffness (shear and compressive stiffness) on the joint kinematics and forces in intervertebral discs (L1-L5), trunk muscles and ligaments for an intermediately flexed position (55 degrees).