Microdamage Accumulation in Bovine Trabecular Bone in Uniaxial Compression

Abstract

In this study we investigated how microdamage accumulated with increasing compressive strain in bovine trabecular bone. We found that little damage is created in the linear elastic region, up to -0.4 percent strain. At an average strain of -0.76 percent +/-0.25 percent, the stress-strain curve became nonlinear, and peaked at -1.91 percent +/-0.55 percent strain. Microdamage increases rapidly during the peak of the stress-strain curve, and a localized band of damage formed. At strains beyond the ultimate strain, the damaged band widened and the density of damage within the band increased. Microdamage occurred as groupings of cracks; the majority of damage occurred as regions of cross-hatching. All microdamage parameters increased with increasing maximum compressive strain. We also observed exponential relationships between crack numerical density and damage (1(o) - (o)Esec/E0) and between crack length density and damage.

Irradiation Does Not Modify Mechanical Properties of Cancellous Bone Under Compression

“…As a result, post hoc power analysis suggests the microdamage measures could only detect effect sizes of 66% to 125% between groups with a power of 0.80 (a = 0.05). The variance in microdamage assays in the current study was comparable to that achieved by other groups [27,32] and most likely requires more precise measurement approaches. Recent developments in threedimensional imaging approaches have been reported to be less variable [30].…”

“…Gamma radiation sterilization (25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35) is commonly used to reduce the risk of disease transmission through bone allograft [15]. In cortical bone, gamma radiation at typical sterilization doses causes reductions in ultimate strength [20], bending strength [13], work to fracture [2,20], fatigue life [1], and resistance to fatigue crack growth [26].…”

Experimental and numerical characterisation of the elasto-plastic properties of bovine trabecular bone and a trabecular bone analogue

“…The present study focuses on elasto-plastic behaviour, in particular focusing on the role of pressure (hydrostatic stress) in the yield behaviour of trabecular bone. Inelastic deformation can occur due to excessive loading or fatigue and may lead to microdamage, fracture, compaction and crushing of trabecular bone (Moore and Gibson, 2002b). Inelastic loading also occurs during the subsidence of prostheses, such as vertebral fusion devices, and the implantation of press-fit prostheses in total joint arthroplasty (Taylor et al, 1998;Kelly and McGarry, 2011).…”

“…Previous studies investigating non-linear trabecular bone mechanics have uncovered viscoelastic, damage and elasto-plastic behaviour (Linde, 1994;Keaveny et al, 1999;Moore and Gibson, 2002a). The present study focuses on elasto-plastic behaviour, in particular focusing on the role of pressure (hydrostatic stress) in the yield behaviour of trabecular bone.…”

Detection of trabecular bone microdamage by micro-computed tomography

“…Microdamage also stimulates adaptive remodeling (Burr, et al, 1985). As such, experimental studies of microdamage formation (Arthur Moore and Gibson, 2002) and propagation (Wang, X and Niebur, 2006;Wang, X S, et al, 2005) should improve our understanding of both bone fragility and mechanobiology. Techniques to assess microdamage that allow further mechanical testing could enhance capabilities to study microdamage effects on bone fragility.…”