Journal Club

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Journal Club

08 January 2012Simin Li

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The structure and mechanics of bone -anniversary review

• John D Currey

• Department of Biology, University of York

• Journal of Materials Science JAN 2012 DOI 10.1007/s10853-011-5914-9

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World wide research Groups in bone community

● UK: 2; ●USA: 6; ● Irland: 1; ●Japan: 1Others: to be added …

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Prof. John. D. Currey: Department of biology, University of York, UK

Publication: 1959-now; 117 publication hits in web of knowledgeResearch group: Biochemistry and BiophysicsResearch interest: specialist in bone tissueThe mechanical properties of mineralised tissues, at the moment, deer antler. The role of microdamage in determining the toughness of boneBooks: The mechanical adaptations of bones; Bones: structure and mechanics 2002,1. The effect of porosity and mineral-content on the youngs modulus of

elasticity of compact-bone (360 cites)2. Changes in the stiffness, strength, and toughness of human cortical bone

with age3. Prediction of mechanical properties of the human calcaneus by

broadband ultrasonic attenuation

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Dr Peter Zioupos : Department of Engineering and Applied Science, Cranfield University, UK

Publication: 1992-now, 70 publication hits in web of knowledge (with Currey, Rho)Research interest: biomaterial hard tissues (simulation and exp)Biomechanics of Materials research group (strain rate, simulation etc)

1. The effect of strain rate on fracture toughness of human cortical bone: a finite element study.

2. Simulation of Creep in non-homogeneous samples of human cortical bone

3. The Effect of Strain Rate on the Mechanical Properties of Human Cortical Bone

4. The importance of the elastic and plastic components of strain in tensile and compressive fatigue of human cortical bone in relation to orthopaedic biomechanics

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Prof. Stephen C. Cowin :Department of Mechanical Engineering The City College, NY USA

Publication: 1972-now; 87 publication hits in web of knowledgeResearch group: Musculoskeletal Biomechanics research centersResearch Interests: (bone theory, test)His current publications are in orthopedic biomechanics and anisotropic elasticity. Books: Bone Mechanics Handbook; Mechanical Properties of Bone; Tissue Mechanics

1. A model for the excitation of osteocytes by mechanical loading-induced bone fluid shear stresses (502)

2. On the dependence of the elasticity and strength of cancellous bone on apparent density

3. A continuous wave technique for the measurement of the elastic properties of cortical bone

4. Bone poroelasticity

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A.Prof. Q. D. Yang: Mechanical and Aerospace Engineering Department University of Michigan, USA; Brian N Cox: Rockwell

Scientific Co., LLC

Publication: 1990-now; 128 publication hits in web of knowledgeGroup: Materials Research GroupResearch interests: (FEA, CZ element, A-FEM)

1. Mixed-mode fracture analyses of plastically-deforming adhesive joints (96)

2. High-Fidelity Simulations of Multiple Fracture Processes in Laminated Composites in Tension

3. Cohesive models for damage evolution in laminated composites4. An augmented finite element method for modeling arbitrary

discontinuities in composite materials

With Ritchie and Nalla

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Prof. Robert O. Ritchie; Ravi Kiran Nalla (RA): Department of Materials Science & Engineering, University of California, Berkeley USA; Materials

Sciences Division, Lawrence Berkeley National Laboratory

Publication: 1986-now; 102 publication hits in web of knowledgeResearch interest: (fracture mechanics)Structure material; fracture mechanics and fatigue-crack propagationBook: Small fatigue cracksRitchie:1. On the relationship between critical tensile stress and fracture toughness in mild steel

(927 in Google scholar)2. Propagation of short fatigue cracks3. Fracture toughness and fatigue-crack propagation in a Zr–Ti–Ni–Cu–Be bulk metallic

glassNalla: 32 hits 4. Mechanistic fracture criteria for the failure of human cortical bone (187)5. Mechanistic aspects of fracture and R-curve behavior in human cortical bone6. On the origin of the toughness of mineralized tissue: microcracking or crack bridging?

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A. Prof. Elisa budyn: Department of Mechanical and Industrial Engineering University of Illinois at Chicago USA

Publication: 2003-now; 8 publication hits in web of knowledgeLaboratory Computational Mechanics LaboratoryResearch interest: (Multi-scale, XFEM)

1. An extended finite element method with higher-order elements for curved cracks (66)

2. A method for multiple crack growth in brittle materials without Remeshing

3. Fracture strength assessment and aging signs detection in human cortical bone using an X-FEM multiple scale approach

4. Bovine Cortical Bone Stiffness and Local Strain are Affected by Mineralization and Morphology

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Rho J Y: Department of Biomedical Engineering, University of Memphis, Memphis USA

Publication: 1997-2011 51 publication hits in web of knowledgeResearch interest: ultrasonic characterization of biomaterials; Nanoindentation

1. Mechanical properties and the hierarchical structure of bone (407)2. The characterization of broadband ultrasound attenuation and fractal

analysis by biomechanical properties3. Elastic properties of human cortical and trabecular lamellar bone measured

by nanoindentation4. Youngs modulus of trabecular and cortical bone material - ultrasonic and

microtensile measurements

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Surgeon group: Dr. ALBERT H. BURSTEIN; Dr. Donald T Reilly

Dr. Donald T Reilly: publication from 1972-2010; 64 publication hits in web of knowledgeALBERT H. BURSTEIN publication from 1968-2008; 145 publication hits in web of knowledge

Most from 1970s (early research of mechanical properties)

1. Elastic and ultimate properties of compact bone tissue (577)2. Review article - mechanical-properties of cortical bone (289)3. Aging of bone tissue - mechanical-properties4. Ultimate properties of bone tissue - effects of yielding

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Prof. D. Taylor: Department of Mechanical Engineering, Trinity Centre for Bioengineering, Trinity College Dublin, Ireland

Publication: 1990-now; 78 publication hits in web of knowledge on ‘bone’ 231 in totalResearch group: Trinity Centre for BioengineeringResearch interest: (The Theory of Critical Distances-TCOD, Bone Mechanics)Development of new approaches in fracture mechanics, using theoretical analysis and experimental testing; Investigations into the strength and fracture of bone, including repair and adaptation; Theoretical modelling and experimental studies

1. PREDICTION OF BONE ADAPTATION USING DAMAGE ACCUMULATION (122)2. Micro-damage and mechanical behaviour: predicting failure and remodeling

in compact bone3. The Cellular Transducer in Damage-Stimulated Bone Remodelling4. Micro-crack accumulation at different intervals during fatigue testing of

compact bone

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Japan group: Prof. Mamoru Mitsuishi: Department of Mechanical Engineering, School

of Engineering, The University of Tokyo, JPPublication: 27 hits in web of knowledge in ‘bone’Research interests: bone cutting -experimental based

newest on bone publication 2010 1. Relationship between anisotropic tissue and cutting stress characteristics

in pig cortical bone2. New cutting method for bone based on its crack propagation

characteristics3. A study of bone micro-cutting characteristics using a newly developed

advanced bone cutting machine tool for total knee arthroplasty4. Fluoroscopic bone fragment tracking for surgical navigation in femur

fracture reduction by incorporating optical tracking of hip joint rotation center

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The structure and mechanics of bone

• Catigrized hierarchical structure into 4 levels– Nano, micro, meso, whole bone

• Different levels of simplification• Fracture mechanics• Size effect• The role of genetics and external forces

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Elastic behaviour

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Fracture behaviour

• Mineral-collagen interaction in bone through either ions or hydrogen bonds:– Ionic interactions – Sliding of layered water films – Sacrificial bonds and hidden lengths – Virtual internal bonds

• Bone becomes insensitive to flaws or cracks at sub-micro level

• Counter-arguments: flaw weaken strength of nanotube compare with flawless one

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Stiffness v.s. toughness

• Stiffness and toughness go against each other• Increase stiffness with increasing

mineralization. – mineral stiffer

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Increase mineral decrease toughness

• Denser crystal inhibit collagen from deformation

• Reduce post-yield deformation• Less micro-damage, means lease total work to

be done for breakage.

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Micro scale level

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Compact bone

Woven bone Osteonal bonePlexiform

bone=fibrolamellar bone=laminar

Lamellar bone

Primary Secondary

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Primary bone

Woven bone

Secondary and plexiform bone

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• Woven bone: found in infant or fractue callus; randomly arranged collagen fibers; pool mechanical properties, quick grow

• Osteonal bone: • primary (no haversian system): are likely formed by mineralization of

cartilage, less lamellae than secondary, small vascular channels (no haversian), may be stronger than secondary

• Secondary osteon (haversian system, cement line): always younger then the bone replaced, so, less mineral, low E(stiffness) than interstitial; cement line: discontinuity between inter and secondary, so cracks are likely initiate there or divert from

• Plexiform bone=fibrolamellar bone=laminar• Rapid grow, offer increased mechanical support for longer periods of time.

more surface area then osteonal, This increases the amount of bone which can be formed in a given time frame and provided a way to more rapidly increase bone stiffness and strength in a short period of time. greater stiffness than primary or secondary cortical bone

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• Lamellae• Osteoclasts• Lacunae• Canaliculi

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Fracture mechanics in micro-scale

• Micro-structure interface, discontinuity cause cracks are likely to initiate or divert from here

• Uncrack bridges• R-curve• Old people low KC and low R-curve (brittle)

• Young people High KC and high R-curve (tough)

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Low mineral content 48% High mineral content85%

Work of fracture 6200J m-2 work of fracture 20 J m-2

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• Size effect remain puzzling

• Bone shape is determined by gene