Prediction of clinically relevant initiation and progression of tears within annulus fibrosus.
Internal disc disruption and annular tears are some of the causes of back and leg pain. It is difficult to observe location of internal damage and its distribution and propagation in cadaveric experiments or via imaging in clinical scenarios. Finite element analysis is useful for understanding the effects of different loading conditions on the location of initiation and propagation of tears in the annulus. In this study, a hyperelastic anisotropic material model in conjunction with biaxial properties was used for modelling annulus fibrosus material under a variety of loading conditions. The loading conditions considered included compression, flexion, extension, and their combinations. Tsai-Wu criterion was used to evaluate the damage, considering strength anisotropy and asymmetry. Damage predictions based on this criterion are in better agreement with available experimental studies and clinical observations, as compared to other approaches. Therefore, the use of Tsai-Wu criterion is suggested as an appropriate mechanical parameter to quantify damage, its initiation locations, and its distribution in annulus fibrosus under different loading conditions. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:113-122, 2017.
Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio, 43606.
Narjes Momeni
NM
Shahraki
Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio, 43606.
Ali
A
Fatemi
Engineering Center for Orthopaedic Research Excellence (E-CORE), Departments of Bioengineering and Orthopaedic Surgery, Colleges of Engineering and Medicine, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio, 43606.
Anand
A
Agarwal
Engineering Center for Orthopaedic Research Excellence (E-CORE), Departments of Bioengineering and Orthopaedic Surgery, Colleges of Engineering and Medicine, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio, 43606.
Vijay K
VK
Goel
D000070616:Annulus Fibrosus / Q000293:injuries* / Q000502:physiology; D020342:Finite Element Analysis; D006801:Humans; D016474:Weight-Bearing
Tsai-Wu criterion; annulus fibrosus; intervertebral disc disruption