Evidence of structural and material adaptation to specific strain features in cortical bone.
Abstract: Functionally induced strains provide epigenetic signaling for bone modeling and remodeling activities. Strain gauge documentation of the equine third metacarpal reveals a neutral axis passing through the craniolateral cortex, resulting in a narrow band of cortex loaded predominantly in tension, with the remainder of the cortex experiencing a wide range of compression strain magnitudes that are maximal in the caudomedial cortex. This predictable strain pattern provides a model for examining the hypothesis that strain mode, magnitude, and strain energy density are potential correlates of compact bone structural and material organization. Methods: Structural and material variables were quantified in nine equine (standard breeds) third metacarpals for comparison with the in vivo strain milieu that was evaluated in thoroughbred horses. The variables quantified included secondary osteon population density (OPD), fractional area of secondary bone (FASB), fractional area of porous spaces, collagen fiber orientation, mineral content (% ash), and cortical thickness. Each bone was sectioned transversely at 50% of length, with subsequent quantification of eight radial sectors and three intracortical regions (periosteal, middle, endosteal). Linear regression analysis compared these variables to magnitudes of corresponding regional in vivo longitudinal strain, shear strain, and strain energy density values reported in the literature. Results: The craniolateral ("tension") cortex of this bone is distinguished by its 30% lower FASB and with the lateral cortex exhibits 20% darker gray level (more longitudinal collagen) compared with the average of all other locations. Conversely, the remaining ("compression") cortices as a group have a high OPD, are more extensively remodeled, and contain more oblique-to-transverse collagen. The caudal cortices (caudomedial, caudal, caudolateral) are significantly thinner (P < 0.01) and have 4% lower mineral content (P < 0.05) than all other locations. Moderately strong correlations exist between collagen fiber orientation and normal strain (r = 0.752) and shear strain (r = 0.555). When normal and shear strains were transformed to their respective absolute values, thus eliminating the effects of strain mode (tension vs. compression), these correlation coefficients decreased markedly. Conclusions: Collagen fiber orientation is related to strain mode and may function to accentuate rather than attenuate bending. These differences may represent adaptations that function synergistically with bone geometry to promote a beneficial strain distribution and loading predictability during functional loading.
Publication Date: 1996-09-01 PubMed ID: 8876823DOI: 10.1002/(SICI)1097-0185(199609)246:1<47::AID-AR6>3.0.CO;2-CGoogle Scholar: Lookup
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- Journal Article
- Research Support
- U.S. Gov't
- Non-P.H.S.
Summary
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The research examines the relationship between strain features and structural and material adaptations in cortical bone using the equine third metacarpal as a model. It suggests that factors like strain mode, magnitude, and strain energy density could be linked to the organization of compact bone.
Research Methodology
- The researchers analysed the structure and material elements of nine equine third metacarpals from standard breeds.
- There were several variables examined in the study, such as the density of secondary osteon population, the proportion of secondary bone, the proportion of porous spaces, the orientation of collagen fibres, mineral content, and cortical thickness.
- Each bone was sectioned at 50% of its length and was further analysed in eight radial sectors and three intra-cortical regions: periosteal, middle, and endosteal.
- Comparisons were drawn using linear regression analysis between these variables and the corresponding in vivo longitudinal strain, shear strain, and strain energy density values found in existing literature.
Key Findings
- The study found that the craniolateral (‘tension’) part of the bone had a 30% lower proportion of secondary bone and 20% more longitudinal collagen orientation compared to other areas.
- On the other hand, the remaining (‘compression’) cortices, depicted high density of secondary osteon population, a higher prevalence of remodeling, and a higher proportion of oblique-to-transverse collagen.
- The caudal section of the cortices was significantly thinner and had 4% less mineral content than all other areas.
- Correlations were observed between collagen fibre orientation and strain features, which decreased when strain mode disparity (tension vs compression) was removed.
Conclusion
- The research concludes that the orientation of collagen fibre is dependent on the strain mode and can potentially amplify bending rather than reducing it.
- These differences might represent adaptations that work in tandem with bone geometry to facilitate a beneficial distribution of strain and predictability during functional loading.
Cite This Article
APA
Skedros JG, Mason MW, Nelson MC, Bloebaum RD.
(1996).
Evidence of structural and material adaptation to specific strain features in cortical bone.
Anat Rec, 246(1), 47-63.
https://doi.org/10.1002/(SICI)1097-0185(199609)246:1<47::AID-AR6>3.0.CO;2-C Publication
Researcher Affiliations
- Bone and Joint Research Laboratories, V.A. Medical Center, Salt Lake City, UT 84148, USA.
MeSH Terms
- Adaptation, Physiological
- Animals
- Bone Development
- Calcification, Physiologic
- Collagen / ultrastructure
- Horses / anatomy & histology
- Horses / growth & development
- Horses / physiology
- Metacarpus / growth & development
- Metacarpus / physiology
- Metacarpus / ultrastructure
- Stress, Mechanical
Citations
This article has been cited 22 times.- Hoenig T, Ackerman KE, Beck BR, Bouxsein ML, Burr DB, Hollander K, Popp KL, Rolvien T, Tenforde AS, Warden SJ. Bone stress injuries. Nat Rev Dis Primers 2022 Apr 28;8(1):26.
- Wu YF, Guo HM. The effect of corticotomy on the compensatory remodeling of alveolar bone during orthodontic treatment. BMC Oral Health 2021 Mar 19;21(1):134.
- Nguyen JT, Barak MM. Secondary osteon structural heterogeneity between the cranial and caudal cortices of the proximal humerus in white-tailed deer. J Exp Biol 2020 Jun 11;223(Pt 11).
- Skedros JG, Doutré MS. Collagen fiber orientation pattern, osteon morphology and distribution, and presence of laminar histology do not distinguish torsion from bending in bat and pigeon wing bones. J Anat 2019 Jun;234(6):748-763.
- Skedros JG, Henrie TR, Doutré MS, Bloebaum RD. Sealed osteons in animals and humans: low prevalence and lack of relationship with age. J Anat 2018 May;232(5):824-835.
- Hayes M, Gao X, Yu LX, Paria N, Henkelman RM, Wise CA, Ciruna B. ptk7 mutant zebrafish models of congenital and idiopathic scoliosis implicate dysregulated Wnt signalling in disease. Nat Commun 2014 Sep 3;5:4777.
- Schlecht SH, Jepsen KJ. Functional integration of skeletal traits: an intraskeletal assessment of bone size, mineralization, and volume covariance. Bone 2013 Sep;56(1):127-38.
- Rubin CT, Seeherman H, Qin YX, Gross TS. The mechanical consequences of load bearing in the equine third metacarpal across speed and gait: the nonuniform distributions of normal strain, shear strain, and strain energy density. FASEB J 2013 May;27(5):1887-94.
- Longrich NR, Field DJ. Torosaurus is not Triceratops: ontogeny in chasmosaurine ceratopsids as a case study in dinosaur taxonomy. PLoS One 2012;7(2):e32623.
- Skedros JG, Clark GC, Sorenson SM, Taylor KW, Qiu S. Analysis of the effect of osteon diameter on the potential relationship of osteocyte lacuna density and osteon wall thickness. Anat Rec (Hoboken) 2011 Sep;294(9):1472-85.
- Skedros JG, Kiser CJ, Keenan KE, Thomas SC. Analysis of osteon morphotype scoring schemes for interpreting load history: evaluation in the chimpanzee femur. J Anat 2011 May;218(5):480-99.
- Gorman KF, Handrigan GR, Jin G, Wallis R, Breden F. Structural and micro-anatomical changes in vertebrae associated with idiopathic-type spinal curvature in the curveback guppy model. Scoliosis 2010 Jun 7;5:10.
- Nyman JS, Leng H, Dong XN, Wang X. Differences in the mechanical behavior of cortical bone between compression and tension when subjected to progressive loading. J Mech Behav Biomed Mater 2009 Dec;2(6):613-9.
- McFarlin SC, Terranova CJ, Zihlman AL, Enlow DH, Bromage TG. Regional variability in secondary remodeling within long bone cortices of catarrhine primates: the influence of bone growth history. J Anat 2008 Sep;213(3):308-24.
- Judex S, Boyd S, Qin YX, Miller L, Müller R, Rubin C. Combining high-resolution micro-computed tomography with material composition to define the quality of bone tissue. Curr Osteoporos Rep 2003 Jun;1(1):11-9.
- Goldman HM, Thomas CD, Clement JG, Bromage TG. Relationships among microstructural properties of bone at the human midshaft femur. J Anat 2005 Feb;206(2):127-39.
- Skedros JG, Hunt KJ. Does the degree of laminarity correlate with site-specific differences in collagen fibre orientation in primary bone? An evaluation in the turkey ulna diaphysis. J Anat 2004 Aug;205(2):121-34.
- Goldman HM, Bromage TG, Boyde A, Thomas CD, Clement JG. Intrapopulation variability in mineralization density at the human femoral mid-shaft. J Anat 2003 Aug;203(2):243-55.
- Skedros JG. A 50-year perspective on the use and potential of artiodactyl calcanei in bone adaptation studies. Biol Rev Camb Philos Soc 2026 Feb;101(1):437-485.
- Skedros JG, Dayton MR, Cronin JT, Mears CS, Bloebaum RD, Wang X, Bachus KN. Roles of collagen cross-links and osteon collagen/lamellar morphotypes in equine third metacarpals in tension and compression tests. J Exp Biol 2024 Jul 15;227(14).
- Skedros JG, Dayton MR, Bloebaum RD, Bachus KN, Cronin JT. Strain-mode-specific mechanical testing and the interpretation of bone adaptation in the deer calcaneus. J Anat 2024 Mar;244(3):411-423.
- Bowers KM, Terrones LD, Sun X, Rifkin R, Croy E, Adair HS 3rd, Mulon PY, Hecht S, Anderson DE. Changes in tibial cortical dimensions and density associated with long-term locking plate fixation in goats. J Exp Orthop 2023 Nov 7;10(1):111.
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