"Maybe this is a little bit more like Jiffy Lube, an oil change", says Stanford researcher Dr. Michael Longaker, M.D.
RELATED: San Francisco scientists' stem cell research could help in COVID-19 fight
Dr. Longaker and his team at Stanford believe they've isolated a technique that could potentially rejuvenate knee joints.
Their target is the shiny surface, known as articular cartilage. When it's damaged, bone can rub on bone, triggering severe pain. One of the few options has been a surgical treatment known as microfracture, which triggers scarring.
"Orthopedic surgeons do these small drill holes and say whatever cell comes up in the bleeding, then each step we take will become a scar cartilage," Dr. Longaker explains.
WATCH: Paralyzed SF man walks again thanks to groundbreaking treatment
While it does get many patients back on the road again, he says the scar tissue, also known a fibrocartilage, lacks the cushion and durability of natural cartilage. But in a critical discovery, Stanford scientists confirmed that skeletal stem cells in bone actually have the ability to grow different materials, including bone, spongy bone, scar-cartilage, and natural cartilage.
"So all we had to do was compare these different processes and figure out how to shut down the bone and fibroblast making process, and then the stem cell makes cartilage exclusively," explains co-investigator Charles Chan, Ph.D.
Dr. Chan says the answer was addition by subtraction. Using the microfracture technique in mice, the Stanford team introduced a drug called Infuse, which stimulates bone growth. But then, they mixed in another agent, similar to the cancer drug Avastin, which blocked part of the bone-making process. The result: the stem cells created natural cartilage instead.
RELATED: British woman plays violin while undergoing brain surgery
"So now we had something I really thought was doable," says Dr. Longaker.
He says all of the drugs and techniques used in the process are already FDA approved for other uses. Now, the challenge for the Stanford team will be to move the clinical trials to larger animals, and, if successful, to humans.
"I'd be disappointed if we couldn't ride this wave to shore," says Dr. Longaker.
And with more than 50 million Americans suffering from arthritic joint pain, it's a ride many other people could eventually appreciate as well.
The Stanford team says their research was made possible in part with help from the taxpayer funded CIRM, the California Institute for Regenerative Medicine.