Biomechanical analysis of the lumbar spine on facet joint force and intradiscal pressure - a finite element study

BMC Musculoskeletal Disorders

Research Article

Po-Chun Lin¹  Hsuan-Teh Hu¹  Mu-Lin Hseih¹  Ching-Sung Kuo²  Kuo-Yuan Huang³  Ruey-Mo Lin⁴  Zheng-Cheng Zhong⁵ 

[1] Department of Civil Engineering, National Cheng Kung University, Tainan, Taiwan;Department of Civil Engineering, National Cheng Kung University, Tainan, Taiwan;Center for General Education, Nan Jeon Institute of Technology, Yenshui, Taiwan;Department of Orthopaedics, National Cheng Kung University Hospital, Tainan, Taiwan;Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan;Department of Orthopaedics, National Cheng Kung University Hospital, Tainan, Taiwan;National Cheng Kung University Hospital Dou-Liou Branch, Douliou, Taiwan;Department of Physical Therapy and Assistive Technology, National Yang-Ming University, Taipei, Taiwan;

关键词: Lumbar Spine;    Nucleus Pulposi;    Facet Joint;    Rotation Moment;    Intradiscal Pressure;   

DOI  :  10.1186/1471-2474-11-151

 received in 2009-12-10, accepted in 2010-07-05,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundFinite element analysis results will show significant differences if the model used is performed under various material properties, geometries, loading modes or other conditions. This study adopted an FE model, taking into account the possible asymmetry inherently existing in the spine with respect to the sagittal plane, with a more geometrically realistic outline to analyze and compare the biomechanical behaviour of the lumbar spine with regard to the facet force and intradiscal pressure, which are associated with low back pain symptoms and other spinal disorders. Dealing carefully with the contact surfaces of the facet joints at various levels of the lumbar spine can potentially help us further ascertain physiological behaviour concerning the frictional effects of facet joints under separate loadings or the responses to the compressive loads in the discs.MethodsA lumbar spine model was constructed from processes including smoothing the bony outline of each scan image, stacking the boundary lines into a smooth surface model, and subsequent further processing in order to conform with the purpose of effective finite element analysis performance. For simplicity, most spinal components were modelled as isotropic and linear materials with the exception of spinal ligaments (bilinear). The contact behaviour of the facet joints and changes of the intradiscal pressure with different postures were analyzed.ResultsThe results revealed that asymmetric responses of the facet joint forces exist in various postures and that such effect is amplified with larger loadings. In axial rotation, the facet joint forces were relatively larger in the contralateral facet joints than in the ipsilateral ones at the same level. Although the effect of the preloads on facet joint forces was not apparent, intradiscal pressure did increase with preload, and its magnitude increased more markedly in flexion than in extension and axial rotation.ConclusionsDisc pressures showed a significant increase with preload and changed more noticeably in flexion than in extension or in axial rotation. Compared with the applied preloads, the postures played a more important role, especially in axial rotation; the facet joint forces were increased in the contralateral facet joints as compared to the ipsilateral ones at the same level of the lumbar spine.

【 授权许可】

CC BY   
© Kuo et al; licensee BioMed Central Ltd. 2010