Knee joints endure immense stress throughout life, and aging often leads to cartilage degradation. Now, researchers at Duke University have engineered a hydrogel that replaces damaged knee cartilage, restoring strength and flexibility.
Athletes and active individuals know the knee faces extreme demands. Yet, osteoarthritis remains its primary foe—a chronic condition from repeated cartilage stress that destroys tissue. In France, it affects 35% of women and 21% of men aged 65-75.
Annually, France implants tens of thousands of knee prostheses, but these last only about 20 years and often reduce mobility. Published in Advanced Functional Materials on June 26, 2020, Duke University experts introduced a hydrogel designed to replace faulty cartilage.
Previous hydrogel attempts fell short, but this one achieves the ideal balance of strength and flexibility—bearing body weight while absorbing shocks. Shaped like a coin-sized disc and composed of 60% water, it supports 45 kilograms (see image below).
In rigorous tests, the hydrogel endured over 100,000 stretches without deformation or tears—matching titanium prostheses in durability. It's highly wear-resistant, non-toxic to humans and the environment.
The innovation lies in its architecture: two intertwined polymer networks—one stretchy like spaghetti for toughness, the other rigid like a basket for compression—plus a cellulose nanofiber mesh that prevents fractures.
Project leaders project market availability by 2023, pending further viability tests.
