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Articular cartilage is a load-bearing, hierarchically organized tissue composed of a network of type II collagen embedded in an aggrecan-rich polyelectrolyte gel. Its ability to resist deformation and dissipate energy arises from spatially varying matrix composition and architecture. Here, we review experimental and theoretical advances that elucidate the mechanistic basis of cartilage shear mechanics. Recent studies have shown that the tissue operates near a rigidity transition, in which small changes in collagen density, cross-linking, or osmotic stress can produce large, nonlinear changes in shear stiffness. We discuss how this behavior is captured by models rooted in rigidity percolation, continuum elasticity, and micromechanics, and how these frameworks connect depth-dependent composition to macroscale mechanical response. Throughout, we emphasize physical principles that describe observations across native, degraded, and engineered tissues, and we highlight emerging strategies for designing cartilage-inspired materials with tunable, anisotropic mechanics, with applications in soft robotics, synthetic gels, and load-bearing biomaterials.
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This content will become publicly available on April 1, 2027
Permeability of bone and cartilage, and stiffness of collagen within cartilage, influence osteochondral fluid transport during cyclic compression: A study in finite elements
- Award ID(s):
- 2140127
- PAR ID:
- 10693391
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of the Mechanical Behavior of Biomedical Materials
- Volume:
- 176
- Issue:
- C
- ISSN:
- 1751-6161
- Page Range / eLocation ID:
- 107350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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