Biomechanical analysis of the annular ligament in Monteggia fractures using finite element models

Abstract Objective: To compare the biomechanical stability of transsacral-transiliac screw fixation and lumbopelvic fixation for “H”- and “U”-type sacrum fractures with traumatic spondylopelvic dissociation.Methods: Finite element models of “H”- and “U”-type sacrum fractures with traumatic spondylopelvic dissociation were created in this study. The models mimicked the standing position of a human. Fixation with transsacral-transiliac screw fixation, lumbopelvic fixation, and bilateral triangular fixation were simulated. Biomechanical tests of instability were performed, and the fracture gap displacement, anteflexion, rotation, and stress distribution after fixation were assessed.Results: For H-type fractures, the three kinds of fixation ranked by stability were bilateral triangular fixation > lumbopelvic fixation > transsacral-transiliac screw fixation in the vertical and anteflexion directions, bilateral triangular fixation > transsacral-transiliac S1 and S2 screw fixation > lumbopelvic fixation in rotation. The largest displacements in the vertical, anteflexion and rotational directions were 0.57234 mm, 0.37923 mm and 0.13076 mm, respectively. For U-type fractures, these kinds of fixation ranked by stability were bilateral triangular fixation > lumbopelvic fixation > transsacral-transiliac S1 and S2 screw fixation > transsacral-transiliac S1 screw fixation in the vertical, anteflexion and rotational directions. The largest displacements in the vertical, anteflexion and rotational directions were 0.38296 mm, 0.33976 mm and 0.05064 mm, respectively.Conclusion: All these kinds of fixation met the mechanical criteria for clinical applications. The biomechanical analysis showed better bilateral balance with transsacral-transiliac screw fixation. The maximal displacement for these types of fixation was less than 1 mm. Percutaneous transsacral-transiliac screw fixation can be considered the best option among these kinds of fracture fixation.

Download Full-text

Biomechanical Analysis of Atlantoaxial Dorsal Fixation Using Finite Element Models

10.21203/rs.3.rs-64835/v1 ◽

2020 ◽

Author(s):

Beomju Bae ◽

Dongwook Kim ◽

Hyejong Oh ◽

Gonhyung Kim

Keyword(s):

Finite Element ◽

Bone Fractures ◽

Clinical Signs ◽

Cord Compression ◽

Biomechanical Analysis ◽

Atlantoaxial Instability ◽

Finite Element Models ◽

Bone Stress ◽

Fixation Techniques ◽

Dorsal Fixation

Abstract Background: Atlantoaxial instability can cause spinal cord compression with clinical signs ranging from cervical pain to tetraplegia and death. Although a variety of dorsal fixation techniques have been described, some of them have been related to the fracture of the dorsal arch of the atlas, leading to surgical failure. We hypothesized that the shape of the dorsal arch of the atlas and types of implants might affect these bone fractures. Thus, the objective of this study was to analyze bone stresses through simulations of the dorsal fixation using finite element models.Results: The width between wires and the length of the bone did not affect the maximum stress on the bone. The maximum bone stress increased as the bone got thinner and the angle of the notch got steeper. The bone with band implant had lower maximum bone stress than that with wire implants. When using wire implants, wires applied beyond the notch of the dorsal arch reduced the maximum bone stress more than wires positioned within it.Conclusions: The fracture of the dorsal arch of the atlas was related to the shape of the bone and types of implant applied. Band implant can effectively reduce the fracture of the dorsal arch compared to wire implant in atlantoaxial dorsal fixation. When considering wire implant, it is recommended to apply wires beyond the notch of the atlas.

Download Full-text

Biomechanical study of transsacral-transiliac screw fixation versus lumbopelvic fixation and bilateral triangular fixation for “H”- and “U”-type sacrum fractures with traumatic spondylopelvic dissociation: a finite element analysis study

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02581-5 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Ye Peng ◽

Gongzi Zhang ◽

Shuwei Zhang ◽

Xinran Ji ◽

Junwei Li ◽

...

Keyword(s):

Finite Element ◽

Screw Fixation ◽

Standing Position ◽

Biomechanical Study ◽

Biomechanical Analysis ◽

Finite Element Models ◽

Biomechanical Stability ◽

Element Analysis ◽

Lumbopelvic Fixation ◽

Biomechanical Tests

Abstract Objective To compare the biomechanical stability of transsacral-transiliac screw fixation and lumbopelvic fixation for “H”- and “U”-type sacrum fractures with traumatic spondylopelvic dissociation. Methods Finite element models of “H”- and “U”-type sacrum fractures with traumatic spondylopelvic dissociation were created in this study. The models mimicked the standing position of a human. Fixation with transsacral-transiliac screw fixation, lumbopelvic fixation, and bilateral triangular fixation were simulated. Biomechanical tests of instability were performed, and the fracture gap displacement, anteflexion, rotation, and stress distribution after fixation were assessed. Results For H-type fractures, the three kinds of fixation ranked by stability were bilateral triangular fixation > lumbopelvic fixation > transsacral-transiliac screw fixation in the vertical and anteflexion directions, bilateral triangular fixation > transsacral-transiliac S1 and S2 screw fixation > lumbopelvic fixation in rotation. The largest displacements in the vertical, anteflexion, and rotational directions were 0.57234 mm, 0.37923 mm, and 0.13076 mm, respectively. For U-type fractures, these kinds of fixation ranked by stability were bilateral triangular fixation > lumbopelvic fixation > transsacral-transiliac S1 and S2 screw fixation > transsacral-transiliac S1 screw fixation in the vertical, anteflexion, and rotational directions. The largest displacements in the vertical, anteflexion, and rotational directions were 0.38296 mm, 0.33976 mm, and 0.05064 mm, respectively. Conclusion All these kinds of fixation met the mechanical criteria for clinical applications. The biomechanical analysis showed better bilateral balance with transsacral-transiliac screw fixation. The maximal displacement for these types of fixation was less than 1 mm. Percutaneous transsacral-transiliac screw fixation can be considered the best option among these kinds of fracture fixation.

Download Full-text

Maximum Principle in Finite Element Models for Convection-Diffusion Phenomena

10.1016/s0304-0208(08)x7173-7 ◽

1983 ◽

Keyword(s):

Finite Element ◽

Maximum Principle ◽

Finite Element Models ◽

Convection Diffusion ◽

Diffusion Phenomena

Download Full-text

Internal Variable and Cellular Automata-Finite Element Models of Heat Treatment

International Journal for Multiscale Computational Engineering ◽

10.1615/intjmultcompeng.v8.i3.40 ◽

2010 ◽

Vol 8 (3) ◽

pp. 267-285 ◽

Cited By ~ 8

Author(s):

Piotr Maciol ◽

Jerzy Gawad ◽

Roman Kuziak ◽

Maciej Pietrzyk

Keyword(s):

Heat Treatment ◽

Finite Element ◽

Cellular Automata ◽

Internal Variable ◽

Finite Element Models

Download Full-text

A Finite Element Analysis of the General Rolling Contact Problem for a Viscoelastic Rubber Cylinder

Tire Science and Technology ◽

10.2346/1.2148795 ◽

1988 ◽

Vol 16 (1) ◽

pp. 18-43 ◽

Cited By ~ 10

Author(s):

J. T. Oden ◽

T. L. Lin ◽

J. M. Bass

Keyword(s):

Finite Element ◽

Variational Principles ◽

Standing Waves ◽

Rolling Contact ◽

Finite Element Models ◽

Viscoelastic Cylinder ◽

Element Analysis ◽

Elastic Rubber ◽

Frictional Effects ◽

Rough Foundation

Abstract Mathematical models of finite deformation of a rolling viscoelastic cylinder in contact with a rough foundation are developed in preparation for a general model for rolling tires. Variational principles and finite element models are derived. Numerical results are obtained for a variety of cases, including that of a pure elastic rubber cylinder, a viscoelastic cylinder, the development of standing waves, and frictional effects.

Download Full-text