Computation of bone remodelling after Duracon knee arthroplasty using a thermodynamic-based model

Area of Science:

• Biomechanical Engineering
• Computational Biology
• Orthopedic Surgery

Background:

• Bone remodeling is crucial for skeletal health and adapts to mechanical stimuli.
• Total knee arthroplasty (TKA) significantly impacts bone density distribution, particularly in the distal femur.
• Existing models often oversimplify the complex interplay of factors influencing bone remodeling post-TKA.

Purpose of the Study:

• To predict bone density evolution in the distal femur after Duracon total knee arthroplasty (TKA) using a novel literature model.
• To investigate the coupling between mechanical loading and chemical reactions in bone remodeling.
• To compare the predictive accuracy of the new model against the strain energy density model.

Main Methods:

• Utilized a new literature model based on chemical kinetics and irreversible thermodynamics.
• Treated bone as a self-organizing system exchanging matter, energy, and entropy.
• Integrated the model into ANSYS finite element software via a macro to compute distal femoral bone density.

Main Results:

• Predicted significant bone loss in the anterior distal femur, consistent with DEXA scan literature.
• Observed greater bone resorption in the lateral condyle compared to the medial condyle post-TKA.
• The model predicted a gradual, uniform bone density evolution, offering more realistic outcomes than the strain energy density model.

Conclusions:

• The developed model provides a more realistic prediction of bone density changes following TKA.
• The coupling of mechanical loading and chemical kinetics offers a superior approach to modeling bone remodeling.
• This computational approach aids in understanding and potentially mitigating bone loss after joint replacement surgery.