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Home / Equine Research Bank / Anat Embryol (Berl) / Mechanical implications of collagen fibre orientation in cor...
Anatomy and embryology1993; 187(3); 239-248; doi: 10.1007/BF00195761

Mechanical implications of collagen fibre orientation in cortical bone of the equine radius.

Abstract: Mechanical test specimens were prepared from the cranial and caudal cortices of radii from eight horses. These were subjected to destructive tests in either tension or compression. The ultimate stress, elastic modulus and energy absorbed to failure were calculated in either mode of loading. Analysis was performed on the specimens following mechanical testing to determine their density, mineral content, mineral density distribution and histological type. A novel technique was applied to sections from each specimen to quantify the predominant collagen fibre orientation of the bone near the plane of fracture. The collagen map for each bone studied was in agreement with the previously observed pattern of longitudinal orientation in the cranial cortex and more oblique to transverse collagen in the caudal cortex. Bone from the cranial cortex had a significantly higher ultimate tensile stress (UTS) than that from the caudal cortex (160 MPa vs 104 MPa; P < 0.001) though this trend was reversed in compression, the caudal cortex becoming relatively stronger (185 MPa vs 217 MPa; P < 0.01). Bone from the cranial cortex was significantly stiffer than that from the caudal cortex both in tension (22 GPa vs 15 GPa; P < 0.001) and compression (19 GPa vs 15 GPa; P < 0.01). Of all the histo-compositional variables studied, collagen fibre orientation was most closely correlated with mechanical properties, accounting for 71% of variation in ultimate tensile stress and 58% of variation in the elastic modulus. Mineral density and porosity were the only other variables to show any significant correlation with either UTS or elastic modulus. The variations in mechanical properties around the equine radius, which occur in close association with the different collagen fibre orientations, provide maximal safety factors in terms of ultimate stress, yet contribute to greater bending of the bone as it is loaded during locomotion, and thus lower safety factors through the higher strains this engenders.
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Publication Date: 1993-03-01 PubMed ID: 8470824DOI: 10.1007/BF00195761Google Scholar: Lookup
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  • Journal Article
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research investigates the impact of collagen fibre orientation on the mechanical properties of horse radii bones. The study found that collagen fibre orientation significantly influences bone stiffness and resistance to stress.

Study Design and Methodology

  • The research team prepared mechanical test specimens from the cranial and caudal cortices of radii from eight horses.
  • These specimens were subjected to destructive tests in either tension or compression.
  • Using this data, the ultimate stress, elastic modulus and energy absorbed to failure were calculated.
  • Post-mechanical testing, each specimen underwent analysis to determine density, mineral content and distribution, as well as the histological type.
  • A new technique was applied to sections from each sample to quantify the principal collagen fibre orientation of the bone near the fracture plane.

Key Findings

  • The map of the collagen fibres for each bone corresponded with the previously observed pattern of longitudinal orientation in the cranial cortex and a more oblique to transverse collagen in the caudal cortex.
  • Significantly higher ultimate tensile stress (UTS) was found in the bone from the cranial cortex compared to that from the caudal cortex.
  • This trend was found to be reversed when tested in compression, with the caudal cortex showing relative strength.
  • The cranial cortex bone was significantly stiffer than the caudal cortex bone both in tension and compression.
  • Out of all the factors examined, collagen fibre orientation held the closest correlation with mechanical properties, accounting for 71% of variation in UTS and 58% of variation in the elastic modulus.
  • Mineral density and porosity were the only other factors to show any significant correlation with either UTS or the elastic modulus.

Conclusions and Implications

  • The differences in mechanical properties around the equine radius, which occur in close association with different collagen fibre orientations, provide maximum safety factors in terms of ultimate stress.
  • However, this contributes to greater bending of the bone during locomotion, and thus lower safety factors through the higher strains this creates.
  • The findings reflect the significance of collagen fibre orientation in understanding the mechanical qualities of bone, potentially guiding advancements in the field of orthopedics and biomechanics.

Cite This Article

APA
Riggs CM, Vaughan LC, Evans GP, Lanyon LE, Boyde A. (1993). Mechanical implications of collagen fibre orientation in cortical bone of the equine radius. Anat Embryol (Berl), 187(3), 239-248. https://doi.org/10.1007/BF00195761

Publication

Anatomy and embryology
ISSN: 0340-2061
NlmUniqueID: 7505194
Country: Germany
Language: English
Volume: 187
Issue: 3
Pages: 239-248

Researcher Affiliations

Riggs, C M
  • Department of Large Animal Clinical Science, Royal Veterinary College, North Mymms, Herts, UK.
Vaughan, L C
    Evans, G P
      Lanyon, L E
        Boyde, A

          MeSH Terms

          • Animals
          • Biomechanical Phenomena
          • Bone Density
          • Bone Remodeling
          • Collagen / physiology
          • Elasticity
          • Horses / physiology
          • Microscopy, Electron, Scanning
          • Radius / metabolism
          • Radius / physiology
          • Radius / ultrastructure
          • Regression Analysis

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