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Updated: Jun 9, 2026
08:36
Fragility Assessment of Bovine Cortical Bone Using Scratch Tests
Published on: November 30, 2017
Changes in bone fatigue resistance due to collagen degradation
Chrystia Wynnyckyj1, Thomas L Willett, Sidney Omelon
1Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Room 840, Toronto, Ontario, Canada M5G 1X5.
Summary
Collagen degradation significantly reduces bone fatigue resistance at high stresses, a change not detectable by standard clinical tools like DXA or QUS. Mechanical Response Tissue Analyzer (MRTA) shows promise in assessing these critical bone property changes.
Area of Science:
- Biomaterials Science
- Orthopedic Research
- Skeletal Biology
Background:
- Current clinical tools (DXA, QUS) assess bone mineral density but miss collagen matrix changes impacting mechanical properties.
- The Mechanical Response Tissue Analyzer (MRTA) directly measures whole bone mechanical properties, offering a potential advantage over existing methods.
Purpose of the Study:
- To investigate how collagen degradation affects bone fatigue resistance.
- To determine if clinical bone assessment tools can detect fatigue-induced mechanical property changes.
Main Methods:
- Emu tibiae were treated with potassium hydroxide (KOH) to degrade collagen over 1-14 days.
- Bones underwent fatigue testing to failure or to induce stiffness loss.
- Mechanical properties were assessed using MRTA and standard mechanical testing.
Main Results:
- Partial fatigue testing decreased bone modulus, detectable by MRTA, even without KOH treatment.
- KOH-treated bones exhibited significantly lower fatigue resistance at high stresses compared to controls.
- No significant differences in fatigue behavior were observed at low stresses.
Conclusions:
- Collagen degradation, induced by KOH, adversely affects bone mechanical properties, particularly fatigue resistance at high stresses.
- Cyclic creep, influenced by collagen, is a likely mechanism for rapid deterioration in degraded bone.
- MRTA can detect fatigue-induced changes in bone stiffness, suggesting its potential for evaluating bone quality beyond mineral content.
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