Multiphysics Modeling in Biomechanics: Challenges and Opportunities

Recently, I established a new group focused on Theoretical and Computational Biomechanics, supported by a grant. This multidisciplinary team includes several members from the audience and originates from the Nonlinear Physics and Mathematical Modeling Group to which I belong. Our primary focus will be on biomechanics while exploring various related aspects.

Biomechanics presents several challenges, many of which are widely recognized within the field. One fundamental issue is the multi-scale nature of biological media. At the cellular level, we encounter a cascade of events related to electrophysiology. However, cell-cell communication, another multi-scale problem, is often less studied. Additionally, the organization of cells within complex microstructural tissues and the emergent phenomena resulting from these interactions also represent multi-scale challenges.

Another significant challenge is the necessity for cells to exchange various types of information and exhibit different physical behaviors to sustain life. Active materials, for instance, must demonstrate contractility, motility, and remodeling—behaviors that differ markedly from classical engineering materials. Furthermore, tissues must endure external loading, making the understanding of their structure and microstructure critical. The energetic properties of cells and tissues also vary between physiological and pathological states. Recognizing these energetic aspects is essential for predicting and potentially treating pathologies.

The primary challenge lies in the integration of knowledge. While mathematical modeling is invaluable, it cannot exist in isolation from experimental data. Today, effective design and prediction require computational modeling as well. We must develop new experiments and methods for assimilating vast amounts of data into mathematical models, particularly generalized theories. Without these theories, addressing aspects such as energetics becomes problematic. Ultimately, the creation and optimization of reliable models depend on these foundational steps, making the integration of knowledge a critical and challenging endeavor.

A relevant example from classical engineering materials is electroactive polymers, which have been extensively studied for years. These materials are often discussed in the context of actuating structures, such as artificial muscles. Despite being in a prominent bioengineering center, we are still distant from successfully creating artificial muscles comparable to their biological counterparts. This gap suggests that we may be lacking essential components at the energetic level.