Study of indentation of a sample equine bone using finite element simulation and single cycle reference point indentation.

This is a study aiming to understand the mechanical behaviour of bone under stress using finite element simulation and experimental validation. The chosen sample is from equine cortical bone. The study validated its findings through simulations and experiments, showing this method’s potential to provide useful insights into bone pathology like bone fragility.

Methods and Materials

• The study elected equine cortical bone as the test material. The choice of material was influenced by its close resemblance to human bone and its applicability to studying bone pathologies like bone fragility.
• The researchers utilised conventional mechanical property tests to first deduce the stress-strain relationships of the equine cortical bone.
• They developed finite element simulation procedures for indentation analyses, which is a technique used to determine the mechanical properties of materials through the application of a concentrated load.

Validation of Simulation Results

• The validity of the simulations was substantiated through experiments involving two operations: (1) Determining the maximum depth of indentation using a procedure called single cycle type of reference point indentation. (2) Identifying the profile and depth of the unloaded, permanent indentation using atomic force microscopy, a tool to measure forces at the nanoscale.
• The inclusion of a yield criterion in the simulation, calibrated by the tested mechanical properties with distinct values in tension and compression, was exemplified.
• Demonstration of the value of damage consideration through a reduction in a mechanical property known as Young’s modulus (which measures the stiffness of a material) was given in predicting the permanent indentation after unloading and recovery.

Results and Conclusion

• Results showed that the predicted indentation depths agree with experimental data, reinforcing the effectiveness of the finite element simulation methods along with experimental validation.
• The study also revealed that indentation depth is affected by multiple factors and the shape of the permanent indentation contains valuable information about the bone material properties.
• In conclusion, these methods could potentially offer valuable insights into bone pathology. Nevertheless, further research is required to ascertain whether these methods and extensions can give valuable insights into specific bone pathologies like the bone fragility of thoroughbred racehorses.