WELL, THIS IS THE 21ST CENTURY, YOU KNOW: Cartilage grown from stem cells could replace hip implants.

“We’ve developed a way to resurface an arthritic joint using a patient’s own stem cells to grow new cartilage, combined with gene therapy to release anti-inflammatory molecules to keep arthritis at bay,” said Farshid Guilak, professor of orthopedic surgery at Washington University, in a statement. “Our hope is to prevent, or at least delay, a standard metal and plastic prosthetic joint replacement.”

The cartilage is made with the patient’s own stem cells taken from fat beneath the skin. A 3-D, biodegradable synthetic scaffold is molded into the shape of the patient’s joint. It is then covered with the cartilage and implanted onto the surface of an arthritic hip. This process helps alleviate arthritic pain and could delay or eliminate the need for hip replacement surgery.

I had been assured that adult stem cells were useless.