More than a million Americans undergo knee and hip replacements each year. It’s a last resort treatment for pain and mobility issues associated with osteoarthritis, a progressive disease caused by degeneration of the protective layer of cartilage that stops our bones grinding together when we sit, stand, write, or move around.

But what if doctors could intervene and repair damaged cartilage before surgery is needed?

For the first time, researchers at the Keck School of Medicine of USC have used a stem cell-based bio-implant to repair cartilage and delay joint degeneration in a large animal model. The work will now advance into humans with support from a $6 million grant from the California Institute of Regenerative Medicine (CIRM).