A novel micromorphic approach captures non-locality in continuum bone remodelling

Area of Science:

• Biomechanics
• Continuum Mechanics
• Biomaterials Science

Background:

• Continuum bone remodeling models treat bone as a continuous material on the macroscale.
• Bone's trabecular microstructure and osteocyte mechanosensing exhibit size-dependent and non-local behaviors.
• Existing models do not fully capture these microstructural influences on macroscale bone remodeling.

Purpose of the Study:

• To introduce a novel phenomenological approach for continuum bone remodeling using a micromorphic formulation.
• To investigate the influence of microstructural characteristics and scale coupling on bone density distribution.
• To compare the proposed micromorphic model against established local formulations.

Main Methods:

• Development of a micromorphic continuum formulation for bone remodeling.
• Application and analysis of the model using benchmark examples: unit cube, rod-shaped bone, and a 3D femur model.
• Comparison of simulation results from the micromorphic and local formulations.

Main Results:

• The micromorphic formulation effectively captures the interaction between macroscale continuum points and their microscale neighborhood.
• Analysis reveals the influence of microcontinuum characteristic size on bone remodeling.
• The model demonstrates how scale coupling affects the distribution of nominal bone density.

Conclusions:

• The micromorphic approach provides a more comprehensive representation of bone remodeling by incorporating microstructural effects.
• This formulation enhances the prediction of macroscale bone density distribution.
• The study highlights the importance of considering micro-macro interactions in bone mechanics.