Implementation of strain rate as a bone remodeling stimulus

Area of Science:

• Biomechanics
• Bone Biology
• Computational Modeling

Background:

• Surface bone remodeling is crucial for skeletal adaptation.
• Existing models often use peak strain magnitude as the primary stimulus.
• The role of strain rate in bone remodeling requires further investigation.

Purpose of the Study:

• To compare surface bone remodeling predictions using strain rate versus peak strain magnitude as stimuli.
• To analyze the evolutionary paths and final shapes predicted by each stimulus.
• To validate the strain rate stimulus against experimental animal data.

Main Methods:

• Development of idealized models for trabecular bone structures (cruciform, square diamond, brick wall patterns).
• Simulation of surface remodeling under periodic compressive loads using both strain rate and peak strain magnitude stimuli.
• Mathematical derivation of conditions under which both stimuli yield similar predictions.
• Application of developed models to experimental data from Goldstein et al. (1991).

Main Results:

• Both strain rate and peak strain magnitude predict the same final bone shape under periodic compressive loading for idealized models.
• Distinct evolutionary pathways to the final shapes were observed for the two stimuli.
• The strain rate stimulus accurately predicted bone remodeling patterns observed in animal experiments.
• Conditions for agreement between the two stimuli were mathematically derived.

Conclusions:

• Strain rate is a viable and potentially more accurate stimulus for surface bone remodeling than peak strain magnitude.
• While final shapes may converge, the dynamic remodeling process differs significantly between the two stimuli.
• The strain rate stimulus offers a promising model for understanding and predicting bone adaptation in response to mechanical loading.