A numerical study to determine the effect of ligament stiffness on kinematics of the lumbar spine during flexion

BMC Musculoskeletal Disorders

Research Article

Stefan Auer¹  Michael Putzer¹  Franz Suess¹  Sebastian Dendorfer¹  William Malpica² 

[1] Laboratory of Biomechanics, Ostbayerische Technische Hochschule Regensburg, Josef-Engert-Straße 9, 93053, Regensburg, Germany;Regensburg Center of Biomedical Engineering, OTH and University Regensburg, Josef-Engert-Straße 9, 93053, Regensburg, Germany;Ortho Kinematics, 110 Wild Basin Rd., Suite 250, 78746, Austin, TX, USA;

关键词: Lumbar spine;    Ligament stiffness;    Musculoskeletal modeling;    Biomechanics;   

DOI  :  10.1186/s12891-016-0942-x

 received in 2015-07-01, accepted in 2016-02-10,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundThere is a wide range of mechanical properties of spinal ligaments documented in literature. Due to the fact that ligaments contribute in stabilizing the spine by limiting excessive intersegmental motion, those properties are of particular interest for the implementation in musculoskeletal models. The aim of this study was to investigate the effect of varying ligament stiffness on the kinematic behaviour of the lumbar spine.MethodsA musculoskeletal model with a detailed lumbar spine was modified according to fluoroscopic recordings and corresponding data files of three different subjects. For flexion, inverse dynamics analysis with a variation of the ligament stiffness matrix were conducted. The influence of several degrees of ligament stiffness on the lumbar spine model were investigated by tracking ligament forces, disc forces and resulting moments generated by the ligaments. Additionally, the kinematics of the motion segments were evaluated.ResultsAn increase of ligament stiffness resulted in an increase of ligament and disc forces, whereas the relative change of disc force increased at a higher rate at the L4/L5 level (19 %) than at the L3/L4 (10 %) level in a fully flexed posture. The same behaviour applied to measured moments with 67 % and 45 %. As a consequence, the motion deflected to the lower levels of the lumbar spine and the lower discs had to resist an increase in loading.ConclusionsHigher values of ligament stiffness over all lumbar levels could lead to a shift of the loading and the motion between segments to the lower lumbar levels. This could lead to an increased risk for the lower lumbar parts.

【 授权许可】

CC BY   
© Putzer et al. 2016