Rational design of mechanical bio-metamaterials for biomedical applications

Mechanical bio-metamaterials are an emerging class of engineered structures tailored to meet complex mechanical and biological demands in biomedical engineering. This review adopts a new perspective, moving beyond traditional formula-based approaches to explore design inspirations shaped by bioinspired, stimuli-responsive, and function-driven factors. We introduce a novel classification framework that organizes these metastructures from simple to complex and from static to dynamic, encompassing a broad range of structural designs. This structural-based classification emphasizes that it is the structure, rather than the material composition, that primarily defines the unique mechanical and biological properties of these materials. Furthermore, we discuss the transformative role of Artificial Intelligence in advancing the design of mechanical bio-metamaterials, facilitating forward and inverse design approaches, additive manufacturing, and predictive modeling. By establishing the term “mechanical bio-metamaterials,” this review connects structural design to biomedical applications in four key areas: engineered microenvironments, tissue implants, external devices, and invasive devices. This holistic approach aims to create accessible insights for a diverse audience, bridging engineering and clinical perspectives and illustrating how these metastructures influence cellular, tissue and organ behaviors. Finally, a roadmap outlines future directions, proposing evolutionary pathways for mechanical bio-metamaterials in healthcare. These innovations hold the potential to drive next-generation biomedical applications, offering improved patient outcomes and fostering creative advancements.