Influence of moment arms on lumbar spine subjected to follower loads

Abstract

In this paper, an influence of moment arms on the lumbar spine subjected to the follower load was investigated. A two-dimensional finite element model of the lumbar spine including idealized trunk muscles was developed to evaluate the muscle force activation generating the follower load when the lengths of moment arms varied. The follower forces, the shear forces and the resultant joint moments were also calculated to confirm the generation of the follower load. Finally, the dependence of the lengths of moment arms on the deformed shape of the lumbar spine model concerning the spinal stability was examined. © Springer-Verlag 2004.