Cortical Bone Model With a Microcrack Under Tensile Loading

Abstract BackgroundBone is a biological material whose mechanical properties are outstanding. The fracture mechanics research of cortical bone is a major challenge to fully understand the complex behavior of biological composites and for the design of future bioinspired materials. MethodsIn order to characterize the fracture mechanics behavior of cortical bone, the plane problem for the cortical bone with a microcrack located in the interstitial tissue under tensile loading was considered. Using the solution for the continuously distributed edge dislocations as Green's functions, the problem was formulated. ResultsThe singular integral equations with Cauchy kernels were obtained. And the numerical results indicate that the stress intensity factor of the microcrack is dominated by the material constants and the geometric parameters of the cortical bone.ConclusionThe numerical results suggest that a soft osteon promotes the microcrack propagation while stiff one repels it, but this interaction effect is limited near the osteon. Some of the numerical results are in accordance with the results obtained and additional numerical results predicted need to be confirmed.

Download Full-text

Micromechanics of Osteonal Cortical Bone Fracture

Journal of Biomechanical Engineering ◽

10.1115/1.2834290 ◽

1998 ◽

Vol 120 (1) ◽

pp. 112-117 ◽

Cited By ~ 57

Author(s):

X. E. Guo ◽

L. C. Liang ◽

S. A. Goldstein

Keyword(s):

Stress Intensity Factor ◽

Stress Intensity ◽

Fracture Mechanics ◽

Intensity Factor ◽

Cortical Bone ◽

Bone Tissue ◽

Cement Line ◽

Linear Elastic ◽

Age Related ◽

Microcrack Propagation

Microcracks have been associated with age-related bone tissue fragility and fractures. The objective of this study was to develop a simple osteonal cortical bone model and apply linear elastic fracture mechanics theory to understand the micromechanics of the fracture process in osteonal cortical bone and its dependence on material properties. The linear fracture mechanics of our composite model of conical bone, consisting of an osteon and interstitial bone tissue, was characterized in terms of a stress intensity factor (SIF) near the tip of a microcrack. The interaction between a microcrack and an osteon was studied for different types of osteons and various spacing between the crack and the osteon. The results of the analysis indicate that the fracture mechanics of osteonal cortical bone is dominated by the modulus ratio between the osteon and interstitial bone tissue: A soft osteon promotes microcrack propagation toward the osteon (and cement line) while a stiff one repels the microcrack from the osteon (and cement line). These findings suggest that newly formed, low-stiffness osteons may toughen cortical bone tissue by promoting crack propagation toward osteons. A relatively accurate empirical formula also was obtained to provide an easy estimation of the influence of osteons on the stress intensity factor.

Download Full-text

Fatigue damage-fracture mechanics interaction in cortical bone

Bone ◽

10.1016/s8756-3282(01)00696-2 ◽

2002 ◽

Vol 30 (3) ◽

pp. 509-514 ◽

Cited By ~ 56

Author(s):

Y.N Yeni ◽

D.P Fyhrie

Keyword(s):

Fracture Mechanics ◽

Cortical Bone ◽

Fatigue Damage

Download Full-text

Experimental evaluation of fracture properties of bovine hip cortical bone using elastic–plastic fracture mechanics

Bio-Medical Materials and Engineering ◽

10.3233/bme-211220 ◽

2021 ◽

pp. 1-10

Author(s):

Waseem Ur Rahman ◽

Rafiullah khan ◽

Noor Rahman ◽

Ziyad Awadh Alrowaili ◽

Baseerat Bibi ◽

...

Keyword(s):

Fracture Toughness ◽

Plastic Deformation ◽

Fracture Mechanics ◽

Cortical Bone ◽

Elastic Deformation ◽

Compact Tension ◽

J Integral ◽

Elastic Plastic ◽

American Society ◽

Fracture Specimens

BACKGROUND: Understanding the fracture mechanics of bone is very important in both the medical and bioengineering field. Bone is a hierarchical natural composite material of nanoscale collagen fibers and inorganic material. OBJECTIVE: This study investigates and presents the fracture toughness of bovine cortical bone by using elastic plastic fracture mechanics. METHODS: The J-integral was used as a parameter to calculate the energies utilized in both elastic deformation (Jel) and plastic deformation (Jpl) of the hipbone fracture. Twenty four different types of specimens, i.e. longitudinal compact tension (CT) specimens, transverse CT specimens, and also rectangular unnotched specimens for tension in longitudinal and transverse orientation, were cut from the bovine hip bone of the middle diaphysis. All CT specimens were prepared according to the American Society for Testing and Materials (ASTM) E1820 standard and were tested at room temperature. RESULTS: The results showed that the average total J-integral in transverse CT fracture specimens is 26% greater than that of longitudinal CT fracture specimens. For longitudinal-fractured and transverse-fractured cortical specimens, the energy used in the elastic deformation was found to be 2.8–3 times less than the energy used in the plastic deformation. CONCLUSION: The findings indicate that the overall fracture toughness measured using the J-integral is significantly higher than the toughness calculated by the stress intensity factor. Therefore, J-integral should be employ to compute the fracture toughness of cortical bone.

Download Full-text

3D analysis of the osteonal and interstitial tissue in human radii cortical bone

Bone ◽

10.1016/j.bone.2019.07.028 ◽

2019 ◽

Vol 127 ◽

pp. 526-536 ◽

Cited By ~ 4

Author(s):

Rémy Gauthier ◽

Hélène Follet ◽

Cécile Olivier ◽

David Mitton ◽

Françoise Peyrin

Keyword(s):

Cortical Bone ◽

Interstitial Tissue ◽

3D Analysis

Download Full-text

A fracture mechanics and mechanistic approach to the failure of cortical bone

Fatigue & Fracture of Engineering Materials & Structures ◽

10.1111/j.1460-2695.2005.00878.x ◽

2005 ◽

Vol 28 (4) ◽

pp. 345-371 ◽

Cited By ~ 89

Author(s):

R. O. RITCHIE ◽

J. H. KINNEY ◽

J. J. KRUZIC ◽

R. K. NALLA

Keyword(s):

Fracture Mechanics ◽

Cortical Bone ◽

Mechanistic Approach

Download Full-text

Finite-Part Singular Integral Equations in Elasticity and Fracture Mechanics

Singular Integral Equations ◽

10.1007/978-3-662-04291-5_3 ◽

2000 ◽

pp. 133-171

Author(s):

E. G. Ladopoulos

Keyword(s):

Fracture Mechanics ◽

Integral Equations ◽

Singular Integral ◽

Singular Integral Equations ◽

Finite Part

Download Full-text

MODELING PULL-OUT TEST OF DENTAL IMPLANTS

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237203000201 ◽

2003 ◽

Vol 15 (04) ◽

pp. 133-142 ◽

Cited By ~ 1

Author(s):

ANNA DOLLAR ◽

KEVIN P. MEADE

Keyword(s):

Continuous Distribution ◽

Singular Integral Equations ◽

Analytical Techniques ◽

Relative Displacement ◽

Interface Failure ◽

Bony Tissue ◽

Bone Implant ◽

Pull Out ◽

Edge Dislocations ◽

Quantities Of Interest

The objective of this paper is to investigate bone-implant interface failure using analytical techniques of fracture mechanics. The implant usually is anchored to the surrounding bone by growth of bony tissue into the surface of the implant. A mechanical interlock is formed between the implant and the bone. Plane strain conditions are imposed. By using a continuous distribution of edge dislocations to represent interfacial debonding, the problem reduced to a system of singular integral equations that was solved numerically using standard collocation techniques. Quantities of interest are the extent of the debonded zone, the relative displacement between the implant and the bone and the stresses at the bone-implant interfaces, all of which depend on the load in a nonlinear fashion.

Download Full-text

Equine cortical bone exhibits rising R-curve fracture mechanics

Journal of Biomechanics ◽

10.1016/s0021-9290(02)00362-7 ◽

2003 ◽

Vol 36 (2) ◽

pp. 191-198 ◽

Cited By ~ 76

Author(s):

C.L. Malik ◽

S.M. Stover ◽

R.B. Martin ◽

J.C. Gibeling

Keyword(s):

Fracture Mechanics ◽

Cortical Bone ◽

Curve Fracture

Download Full-text

Effects of Microstructure Characteristics of Cortical Bone on its Microcrack Propagation

E3S Web of Conferences ◽

10.1051/e3sconf/202018503027 ◽

2020 ◽

Vol 185 ◽

pp. 03027

Author(s):

Yu-xi Liu ◽

Ai-hua Li ◽

Yan-hua Li

Keyword(s):

Crack Initiation ◽

Cortical Bone ◽

Phase Model ◽

Propagation Path ◽

Extended Finite Element ◽

Two Phase ◽

Cement Line ◽

Microstructure Characteristics ◽

Microcrack Propagation ◽

Analysis Models

Scanning electron microscope (SEM) was used to observe and analyze the microstructure of the cross section of cortical bone. The observation results illustrated that the cortical bone is composed of cylindrical osteons and interstitial bone between osteons, and the osteon are unevenly distributed. Based on the microstructure characteristics of cortical bone, three types of cortical bone mesoscopic analysis models were established. Then, the extended finite element method (X-FEM) was used to simulate the microcrack propagation process in bone. The simulate results show that the crack initiation strain of the two-phase model is 19.1% larger than that of the single-phase model, and the three-phase model is 57.8% larger than that of the two-phase model, which demonstrated that the osteons and cement line can significantly enhance the crack initiation strain of bone. In addition, under the same boundary conditions, the model with cement line can effectively change the propagation path of microcrack and prevent the propagation of crack. Therefore, the cement lines in cortical bone can effectively increase the fracture resistance of bone and enhance the fracture toughness of cortical bone.

Download Full-text