Micro-Computed Tomography of Microdamage in Cortical Bone

The exact effects of microdamage on bone strength in vivo are still not well understood, in part due to our limited capability for imaging and measuring microdamage nondestructively. Most current methods of imaging microdamage are inherently twodimensional and provide minimal information regarding the three-dimensional distribution or orientation of cracks. The objective of this study was to develop a nondestructive technique for three-dimensional imaging and quantification of microdamage in cortical bone.

A new three-dimensional and nondestructive technique was developed to image microdamage in cortical bone using micro-computed tomography (micro-CT). In order to image microdamage in micro-CT, lead sulfide (PbS) and barium sulfate (BaSO4) were precipitated within tissue as contrast agents. Four-point bending fatigue was used to induce microdamage bovine cortical bone beams. Symmetric loading on the beam enabled paired specimens to be produced with similar microdamage accumulation. The new technique was validated by direct comparison with paired specimens stained by calcein and imaged using ultraviolet light microscopy. Microdamage in double-notched bovine cortical bone beams was also studied in order to investigate microdamage accumulation at a stress concentration. The new technique was validated qualitatively by comparison between the observed staining shape using micro-CT and finite element analysis, and quantitatively by positively correlating the amount of stain with the number of loading cycles. The combined studies elucidated microdamage mechanisms in bovine plexiform bone under relatively low load and high cycle number. Microcracks initiated at vasculature and lacunae, and propagated along the weak interface between lamellae in the plane of the vascular network.

A limitation of the precipitated contrast agents was incomplete stain penetration. Further investigation showed that the problem could be alleviated by decreasing the specimen size, albeit counter to the objective of this study. Furthermore, in vivo imaging would require that micro-CT contrast agents be deliverable. Therefore, barium sulfate nanoparticles less than 100 nm in size were synthesized. The effects of the reagent solution concentration, molar ratio, feeding order, feeding speed and pH were investigated. Finally, the feasibility of imaging the synthesized barium sulfate nanoparticles in bone using micro-CT was verified.

Year	Entry
1998	Zioupos P, Casinos A. Cumulative damage and the response of human bone in two-step loading fatigue. J Biomech. September 1998;31(9):825-833.
1989	Schaffler MB, Radin EL, Burr DB. Mechanical and morphological effects of strain rate on fatigue of compact bone. Bone. 1989;10(3):207-214.
1988	Schaffler MB, Burr DB. Stiffness of compact bone: effects of porosity and density. J Biomech. 1988;21(1):13-16.
1995	Schaffler MB, Choi K, Milgrom C. Aging and matrix microdamage accumulation in human compact bone. Bone. December 1995;17(6):521-525.
1998	Roschger P, Fratzl P, Eschberger J, Klaushofer K. Validation of quantitative backscattered electron imaging for the measurement of mineral density distribution in human bone biopsies. Bone. October 1998;23(4):319-326.
2001	Currey JD. Ontogenetic changes in compact bone material properties. In: Cowin SC, ed. Bone Mechanics Handbook. 2nd ed. Boca Raton, FL: CRC Press; 2001:chap 19.
1987	Schaffler MB, Burr DB, Frederickson RG. Morphology of the osteonal cement line in human bone. Anat Rec. March 1987;217(3):223-228.
1979	Lakes R, Saha S. Cement line motion in bone. Science. May 4, 1979;204(4392):501-503.
1981	Frasca P. Scanning-electron microscopy studies of "ground substance" in the cement lines, resting lines, hypercalcified rings and reversal lines of human cortical bone. Acta Anat. 1981;109(2):115-121.
1990	Burr DB, Milgrom C, Boyd RD, Higgins WL, Robin G, Radin EL. Experimental stress fractures of the tibia: biological and mechanical aetiology in rabbits. J Bone Joint Surg. May 1990;72B(3):370-375.
1960	Frost HM. Presence of microscopic cracks in vivo in bone. Henry Ford Hosp Med Bull. 1960;8(1):25-35.
1993	Mori S, Burr DB. Increased intracortical remodeling following fatigue damage. Bone. March–April 1993;14(2):103-109.
1997	Jepsen KJ, Davy DT. Comparison of damage accumulation measures in human cortical bone. J Biomech. September 1997;30(9):891-894.
1977	Carter DR, Hayes WC. Compact bone fatigue damage, I: residual strength and stiffness. J Biomech. 1977;10(5-6):325-337.
2002	Turner CH. Biomechanics of bone: determinants of skeletal fragility and bone quality. Osteoporos Int. February 2002;13(2):97-104.
2004	Nalla RK, Kruzic JJ, Kinney JH, Ritchie RO. Effect of aging on the toughness of human cortical bone: evaluation by R-curves. Bone. December 2004;35(6):1240-1246.
2003	Nalla RK, Kinney JH, Ritchie RO. Mechanistic fracture criteria for the failure of human cortical bone. Nat Mater. 2003;2(3):164-168.
1988	Burr DB, Schaffler MB, Frederickson RG. Composition of the cement line and its possible mechanical role as a local interface in human compact bone. J Biomech. 1988;21(11):939-945.
1998	Taylor D, Lee TC. Measuring the shape and size of microcracks in bone. J Biomech. December 1998;31(12):1177-1180.
2003	Ammann P, Rizzoli R. Bone strength and its determinants. Osteoporos Int. March 2003;14(suppl 3):S13-S18.
1985	Burr DB, Martin RB, Schaffler MB, Radin EL. Bone remodeling in response to in vivo fatigue microdamage. J Biomech. 1985;18(3):189-200.
2000	O’Brien FJ, Taylor D, Dickson GR, Lee TC. Visualisation of three‐dimensional microcracks in compact bone. J Anat. October 2000;197(3):413-420.
2003	O’Brien FJ, Taylor D, Lee TC. Microcrack accumulation at different intervals during fatigue testing of compact bone. J Biomech. July 2003;36(7):973-980.
2002	O’Brien FJ, Taylor D, Lee TC. An improved labelling technique for monitoring microcrack growth in compact bone. J Biomech. April 2002;35(4):523-526.
1996	Pattin CA, Caler WE, Carter DR. Cyclic mechanical property degradation during fatigue loading of cortical bone. J Biomech. January 1996;29(1):69-79.
1987	Reid SA, Boyde A. Changes in the mineral density distribution in human bone with age: image analysis using backscattered electrons in the SEM. J Bone Miner Res. February 1987;2(1):13-22.
1989	Forwood MR, Parker AW. Microdamage in response to repetitive torsional loading in the rat tibia. Calcif Tiss Int. July 1989;45(1):47-53.
2002	Yeni YN, Fyhrie DP. Fatigue damage-fracture mechanics interaction in cortical bone. Bone. March 2002;30(3):509-514.
1994	Schaffler MB, Pitchford WC, Choi K, Riddle JM. Examination of compact bone microdamage using back-scattered electron microscopy. Bone. September–October 1994;15(5):483-488.
1997	Ray NF, Chan JK, Thamer M, Melton LJ III. Medical expenditures for the treatment of osteoporotic fractures in the United States in 1995: report from the National Osteoporosis Foundation. J Bone Miner Res. January 1997;12(1):24-35.
2004	Sobelman OS, Gibeling JC, Stover SM, Hazelwood SJ, Yeh OC, Shelton DR, Martin RB. Do microcracks decrease or increase fatigue resistance in cortical bone? J Biomech. September 2004;37(9):1295-1303.
1990	Schaffler MB, Radin EL, Burr DB. Long-term fatigue behavior of compact bone at low strain magnitude and rate. Bone. 1990;11(5):321-326.
1976	Carter DR, Hayes WC. Fatigue life of compact bone, I: effects of stress amplitude, temperature and density. J Biomech. 1976;9(1):27-34.
1994	Zioupos P, Currey JD, Sedman AJ. An examination of the micromechanics of failure of bone and antler by acoustic emission tests and laser scanning confocal microscopy. Med Eng Phys. May 1994;16(3):203-212.
1974	Reilly DT, Burstein AH. The mechanical properties of cortical bone. J Bone Joint Surg. 1974;56A(5):1001-1022.
1997	Vashishth D, Behiri JC, Bonfield W. Crack growth resistance in cortical bone: concept of microcrack toughening. J Biomech. August 1997;30(8):763-769.
2000	Vashishth D, Tanner KE, Bonfield W. Contribution, development and morphology of microcracking in cortical bone during crack propagation. J Biomech. September 2000;33(9):1169-1174.
1982	Martin RB, Burr DB. A hypothetical mechanism for the stimulation of osteonal remodelling by fatigue damage. J Biomech. 1982;15(3):137-139.
1997	Norman TL, Wang Z. Microdamage of human cortical bone: incidence and morphology in long bones. Bone. April 1997;20(4):375-379.
2001	Jee WSS. Integrated bone tissue physiology: anatomy and physiology. In: Cowin SC, ed. Bone Mechanics Handbook. 2nd ed. Boca Raton, FL: CRC Press; 2001:chap 1.
2003	Martin RB. Fatigue microdamage as an essential element of bone mechanics and biology. Calcif Tiss Int. August 2003;73(2):101-107.
1997	Burr DB, Forwood MR, Fyhrie DP, Martin RB, Schaffler MB, Turner CH. Bone microdamage and skeletal fragility in osteoporotic and stress fractures. J Bone Miner Res. January 1997;12(1):6-15.
2003	Burr D. Microdamage and bone strength. Osteoporos Int. September 2003;14(suppl 5):S67-S72.
1995	Burr DB, Hooser M. Alterations to the en bloc basic fuchsin staining protocol for the demonstration of microdamage produced in vivo. Bone. October 1995;17(4):431-433.
2001	Akkus O, Rimnac CM. Cortical bone tissue resists fatigue fracture by deceleration and arrest of microcrack growth. J Biomech. June 2001;34(6):757-764.
1990	Burr DB, Stafford T. Validity of the bulk-staining technique to separate artifactual from in vivo bone microdamage. Clin Orthop Relat Res. November 1990;260:305-308.
2000	Lee TC, Arthur TL, Gibson LJ, Hayes WC. Sequential labelling of microdamage in bone using chelating agents. J Orthop Res. March 2000;18(2):322-325.
2000	Lee TC, O'Brien FJ, Taylor D. The nature of fatigue damage in bone. Int J Fract. November 2000;22(10):847-853.
1994	Zioupos P, Currey JD. The extent of microcracking and the morphology of microcracks in damaged bone. J Mater Sci. 1994;29(4):978-986.
1998	Burr DB, Turner CH, Naick P, Forwood MR, Ambrosius W, Hasan MS, Pidaparti R. Does microdamage accumulation affect the mechanical properties of bone? J Biomech. April 1998;31(4):337-345.

Year

Entry

1998

Zioupos P, Casinos A. Cumulative damage and the response of human bone in two-step loading fatigue. J Biomech. September 1998;31(9):825-833.

1989

Schaffler MB, Radin EL, Burr DB. Mechanical and morphological effects of strain rate on fatigue of compact bone. Bone. 1989;10(3):207-214.

1988

Schaffler MB, Burr DB. Stiffness of compact bone: effects of porosity and density. J Biomech. 1988;21(1):13-16.

1995

Schaffler MB, Choi K, Milgrom C. Aging and matrix microdamage accumulation in human compact bone. Bone. December 1995;17(6):521-525.

1998

Roschger P, Fratzl P, Eschberger J, Klaushofer K. Validation of quantitative backscattered electron imaging for the measurement of mineral density distribution in human bone biopsies. Bone. October 1998;23(4):319-326.

2001

Currey JD. Ontogenetic changes in compact bone material properties. In: Cowin SC, ed. Bone Mechanics Handbook. 2nd ed. Boca Raton, FL: CRC Press; 2001:chap 19.

1987

Schaffler MB, Burr DB, Frederickson RG. Morphology of the osteonal cement line in human bone. Anat Rec. March 1987;217(3):223-228.

1979

Lakes R, Saha S. Cement line motion in bone. Science. May 4, 1979;204(4392):501-503.

1981

Frasca P. Scanning-electron microscopy studies of "ground substance" in the cement lines, resting lines, hypercalcified rings and reversal lines of human cortical bone. Acta Anat. 1981;109(2):115-121.

1990

Burr DB, Milgrom C, Boyd RD, Higgins WL, Robin G, Radin EL. Experimental stress fractures of the tibia: biological and mechanical aetiology in rabbits. J Bone Joint Surg. May 1990;72B(3):370-375.

1960

Frost HM. Presence of microscopic cracks in vivo in bone. Henry Ford Hosp Med Bull. 1960;8(1):25-35.

1993

Mori S, Burr DB. Increased intracortical remodeling following fatigue damage. Bone. March–April 1993;14(2):103-109.

1997

Jepsen KJ, Davy DT. Comparison of damage accumulation measures in human cortical bone. J Biomech. September 1997;30(9):891-894.

1977

Carter DR, Hayes WC. Compact bone fatigue damage, I: residual strength and stiffness. J Biomech. 1977;10(5-6):325-337.

2002

Turner CH. Biomechanics of bone: determinants of skeletal fragility and bone quality. Osteoporos Int. February 2002;13(2):97-104.

2004

Nalla RK, Kruzic JJ, Kinney JH, Ritchie RO. Effect of aging on the toughness of human cortical bone: evaluation by R-curves. Bone. December 2004;35(6):1240-1246.

2003

Nalla RK, Kinney JH, Ritchie RO. Mechanistic fracture criteria for the failure of human cortical bone. Nat Mater. 2003;2(3):164-168.

1988

Burr DB, Schaffler MB, Frederickson RG. Composition of the cement line and its possible mechanical role as a local interface in human compact bone. J Biomech. 1988;21(11):939-945.

1998

Taylor D, Lee TC. Measuring the shape and size of microcracks in bone. J Biomech. December 1998;31(12):1177-1180.

2003

Ammann P, Rizzoli R. Bone strength and its determinants. Osteoporos Int. March 2003;14(suppl 3):S13-S18.

1985

Burr DB, Martin RB, Schaffler MB, Radin EL. Bone remodeling in response to in vivo fatigue microdamage. J Biomech. 1985;18(3):189-200.

2000

O’Brien FJ, Taylor D, Dickson GR, Lee TC. Visualisation of three‐dimensional microcracks in compact bone. J Anat. October 2000;197(3):413-420.

2003

O’Brien FJ, Taylor D, Lee TC. Microcrack accumulation at different intervals during fatigue testing of compact bone. J Biomech. July 2003;36(7):973-980.

2002

O’Brien FJ, Taylor D, Lee TC. An improved labelling technique for monitoring microcrack growth in compact bone. J Biomech. April 2002;35(4):523-526.

1996

Pattin CA, Caler WE, Carter DR. Cyclic mechanical property degradation during fatigue loading of cortical bone. J Biomech. January 1996;29(1):69-79.

1987

Reid SA, Boyde A. Changes in the mineral density distribution in human bone with age: image analysis using backscattered electrons in the SEM. J Bone Miner Res. February 1987;2(1):13-22.

1989

Forwood MR, Parker AW. Microdamage in response to repetitive torsional loading in the rat tibia. Calcif Tiss Int. July 1989;45(1):47-53.

2002

Yeni YN, Fyhrie DP. Fatigue damage-fracture mechanics interaction in cortical bone. Bone. March 2002;30(3):509-514.

1994

Schaffler MB, Pitchford WC, Choi K, Riddle JM. Examination of compact bone microdamage using back-scattered electron microscopy. Bone. September–October 1994;15(5):483-488.

1997

Ray NF, Chan JK, Thamer M, Melton LJ III. Medical expenditures for the treatment of osteoporotic fractures in the United States in 1995: report from the National Osteoporosis Foundation. J Bone Miner Res. January 1997;12(1):24-35.

2004

Sobelman OS, Gibeling JC, Stover SM, Hazelwood SJ, Yeh OC, Shelton DR, Martin RB. Do microcracks decrease or increase fatigue resistance in cortical bone? J Biomech. September 2004;37(9):1295-1303.

1990

Schaffler MB, Radin EL, Burr DB. Long-term fatigue behavior of compact bone at low strain magnitude and rate. Bone. 1990;11(5):321-326.

1976

Carter DR, Hayes WC. Fatigue life of compact bone, I: effects of stress amplitude, temperature and density. J Biomech. 1976;9(1):27-34.

1994

Zioupos P, Currey JD, Sedman AJ. An examination of the micromechanics of failure of bone and antler by acoustic emission tests and laser scanning confocal microscopy. Med Eng Phys. May 1994;16(3):203-212.

1974

Reilly DT, Burstein AH. The mechanical properties of cortical bone. J Bone Joint Surg. 1974;56A(5):1001-1022.

1997

Vashishth D, Behiri JC, Bonfield W. Crack growth resistance in cortical bone: concept of microcrack toughening. J Biomech. August 1997;30(8):763-769.

2000

Vashishth D, Tanner KE, Bonfield W. Contribution, development and morphology of microcracking in cortical bone during crack propagation. J Biomech. September 2000;33(9):1169-1174.

1982

Martin RB, Burr DB. A hypothetical mechanism for the stimulation of osteonal remodelling by fatigue damage. J Biomech. 1982;15(3):137-139.

1997

Norman TL, Wang Z. Microdamage of human cortical bone: incidence and morphology in long bones. Bone. April 1997;20(4):375-379.

2001

Jee WSS. Integrated bone tissue physiology: anatomy and physiology. In: Cowin SC, ed. Bone Mechanics Handbook. 2nd ed. Boca Raton, FL: CRC Press; 2001:chap 1.

2003

Martin RB. Fatigue microdamage as an essential element of bone mechanics and biology. Calcif Tiss Int. August 2003;73(2):101-107.

1997

Burr DB, Forwood MR, Fyhrie DP, Martin RB, Schaffler MB, Turner CH. Bone microdamage and skeletal fragility in osteoporotic and stress fractures. J Bone Miner Res. January 1997;12(1):6-15.

2003

Burr D. Microdamage and bone strength. Osteoporos Int. September 2003;14(suppl 5):S67-S72.

1995

Burr DB, Hooser M. Alterations to the en bloc basic fuchsin staining protocol for the demonstration of microdamage produced in vivo. Bone. October 1995;17(4):431-433.

2001

Akkus O, Rimnac CM. Cortical bone tissue resists fatigue fracture by deceleration and arrest of microcrack growth. J Biomech. June 2001;34(6):757-764.

1990

Burr DB, Stafford T. Validity of the bulk-staining technique to separate artifactual from in vivo bone microdamage. Clin Orthop Relat Res. November 1990;260:305-308.

2000

Lee TC, Arthur TL, Gibson LJ, Hayes WC. Sequential labelling of microdamage in bone using chelating agents. J Orthop Res. March 2000;18(2):322-325.

2000

Lee TC, O'Brien FJ, Taylor D. The nature of fatigue damage in bone. Int J Fract. November 2000;22(10):847-853.

1994

Zioupos P, Currey JD. The extent of microcracking and the morphology of microcracks in damaged bone. J Mater Sci. 1994;29(4):978-986.

1998

Burr DB, Turner CH, Naick P, Forwood MR, Ambrosius W, Hasan MS, Pidaparti R. Does microdamage accumulation affect the mechanical properties of bone? J Biomech. April 1998;31(4):337-345.

Year	Entry
2011	Landrigan MD, Li J, Turnbull TL, Burr DB, Niebur GL, Roeder RK. Contrast-enhanced micro-computed tomography of fatigue microdamage accumulation in human cortical bone. Bone. March 2011;48(3):443-450.
2007	Akhtar R. Micromechanical Behaviour of Bone [PhD thesis]. University of Manchester; 2007.
2013	Turnbull TL. The Spatial Distribution of Fatigue Microdamage Accumulation in Cortical Bone and Factors Influencing Fracture Risk [PhD thesis]. University of Notre Dame; July 2013.

Year

Entry

2011

Landrigan MD, Li J, Turnbull TL, Burr DB, Niebur GL, Roeder RK. Contrast-enhanced micro-computed tomography of fatigue microdamage accumulation in human cortical bone. Bone. March 2011;48(3):443-450.

2007

Akhtar R. Micromechanical Behaviour of Bone [PhD thesis]. University of Manchester; 2007.

2013

Turnbull TL. The Spatial Distribution of Fatigue Microdamage Accumulation in Cortical Bone and Factors Influencing Fracture Risk [PhD thesis]. University of Notre Dame; July 2013.