3-D printing technology allows doctors to create new cartilage for worn-out joints

Medical breakthrough could be game-changer for knee replacements

HOUSTON – About 600,000 Americans undergo knee-replacement therapy every year in the United States to rid themselves of the pain of worn-out joints.

Instead of metal or plastic, imagine doctors inserting a strand of lab-grown cartilage to rejuvenate and cushion the joint. It could be medicine’s next big thing.

It could be from years of grinding, or climbing or just advancing age. Sometimes the knees aren’t what they used to be.

“People can’t even walk," Penn State professor Ibrahim Ozbolat said. "They have a hard time in their daily lives."

Inside the lab, Ozbolat and his team are engineering a solution.

Ozbolat is an expert in 3-dimensional bio-printing, the technique of printing layers of living cells to create a 3-D object, such as a nose, constructed from silicone and printed in the lab.

Now, the team is moving down the human body to the knee, producing cartilage patches to repair defects.

“Many of the strategies that we look at for repairing osteochondral defects involve stem cells,” biomedical engineer Daniel Hayes said.

There are no blood vessels in cartilage tissue, so researchers said it’s a good type of tissue for bio-printing. Using cow cells as a test, Ozbolat’s team grows the cartilage into strands that can be used as an ink substitute.

“So the bio-ink is the biological version of the ink that is used in printers like you can see here,” Ozbolat said.

In the future, Ozbolat said, stem cells would be removed from a patient and cultured in a lab. The cartilage is printed and then transplanted back into a patient. This will allow scientists to print new and compatible human parts someday.

If this process eventually is applied to humans, each individual would probably need to supply his or her own cells to avoid tissue rejection.