Easy on the Joints

April 1, 2007
X-ray of a bone joint

3D4Medical.com

Using a unique weaving machine of their design, Duke Medical Center researchers have created a three-dimensional fabric “scaffold” that could greatly improve the ability of physicians to repair cartilage in damaged joints using a patient’s own stem cells.

Cartilage is a type of connective tissue that lines the ends of bones, providing cushioning and a smooth surface for their movement within the joint. Damage to cartilage can be very painful and is difficult for doctors to treat because the tissue lacks a supply of blood, nerve, and lymph, and has limited capacity for repair.

Strategies currently in use for treating cartilage damage include surgery and implants. In some cases doctors can remove cartilage cells from patients and then “grow” them in a laboratory to form new cartilage. But it can take several months to grow a piece of cartilage large enough to be implanted back into the patient, and often, this laboratory-grown cartilage is not as durable as native cartilage.

In laboratory tests, the fabric scaffold that the researchers have created had the same mechanical properties as native cartilage. In the near future, surgeons will be able to impregnate custom-designed scaffolds with cartilage-forming stem cells and chemicals that stimulate their growth, and then implant them into patients during a single procedure, the researchers say.

“By taking a synthetic material that already has the properties of cartilage and combining it with living cells, we can build a human tissue that can be integrated rapidly into the body, representing a new approach in the field of tissue engineering,” says Franklin Moutos, a graduate student in the orthopedic bioengineering laboratory who designed and built the weaving machine.

“Once implanted, the cartilage cells will grow throughout the scaffold, and over time the scaffold will slowly dissolve, leaving the new cartilage tissue,” he says. “The use of this scaffold will also permit doctors to treat larger areas of cartilage damage, since the current approaches are only suitable for repairing smaller areas of cartilage damage or injury.”
The researchers reported the new technology in the journal Nature Materials. Moutos says he believes the scaffold could be used in clinical trials within three or four years.