Engineers Create Artificial Cartilage with Hydrogel and Scaffold

Cartilage is one of the most important tissues in the body. It can keep joints moving smoothly and painlessly. Yet over time, cartilage can become damaged or worn down, which can cause pain and lack of mobility. Now, scientists have combined two innovative technologies to create artificial cartilage.

Articular cartilage is the tissue on the ends of bonds where they meet at joints in the body. For example, there's cartilage in the knees, shoulders and hips. This cartilage can erode over time and the replacement of this tissue could bring relief to millions. Yet actually replicating this tissue is a challenge.

In 2007, researchers actually developed a three-dimensional fabric "scaffold" into which stem cells could be injected and successfully "grown" into cartilage tissue. It's constructed out of miniscule woven fibers and each layer of the scaffold is about as thick as a human hair. The finished product is merely a millimeter thick. Yet the main challenge has been to develop the right material to fill the empty spaces of the scaffold.

Now, scientists may have done just that. Using an extremely tough, flexible and formable hydrogel, the researchers worked to integrate it into the fabric of the 3D woven scaffolds.

"It has all the mechanical properties of native cartilage and can withstand wear and tear without fracturing," said Xuanhe Zhao, one of the researchers, in a news release.

The resulting composite material stood up well against previous materials using the same scaffolding. The material was tougher than the competition with a lower coefficient of friction, which would be important when it comes to keeping patients from pain. While it didn't quite meet the standards of natural cartilage, though, it easily outperformed all known potential artificial replacements to date.

"From a mechanical standpoint, this technology remedies the issues that other types of synthetic cartilage have had," said Zhao in a news release. "It's a very promising candidate for artificial cartilage in the future."

The findings are published in the journal Advanced Functional Materials.