Numerical analysis on quantitative role of trunk muscles in spinal stabilization

Abstract

The human lumbar spine can support much larger compressive loads if it is applied along a follower load path that approximates the tangent to the curve of the lumbar spine compared with the vertical load path. In this study, a musculoskeletal finite element model of the simplified lumbar spine including idealized psoas major muscles in the frontal plane was developed and the quantitative role of psoas major muscles was investigated to generate the follower load by using stiffness methods when vertical loads are given. The muscle force distributions were analyzed under various loading cases and follower load constraints. The validity of the developed model was assessed through comparison with previous modeling and experimental studies.