Patient's own cells can repair knee

January 22, 2009 7:02:26 PM PST
A new technique for repairing damaged knees uses a patient's own cells to grow new cartilage. Researchers at UCSF are taking part in the clinical trials.

Ten years after tearing the cartilage in his knee, Michael Coats was facing the final option for his painfully deteriorated joint -- a full knee replacement.

"I'm thinking I'm too young for this," said Michael Coats, a knee patient.

Then Coats learned about an experimental treatment that might allow surgeomichns to patch the chipped surface on his knee joint, known as the articular cartilage.

In a series of surgeries, doctors removed cartilage cells from his knee, then cultured them using a kind of three dimensional frame, to grow a natural piece of cartilage. Dr. Benjamin Ma, M.D., is a surgeon at UCSF in San Francisco, is participating in the nationwide trial.

"We can actually biopsy cartilage cells from the body, grow them in a lab and then implant into a scaffold, almost giving them a house they can live in. Once they live in there, they generally grow cartilage or protoliken, which is the structure of what articular cartilage is and now you have a piece of cartilage, and you can implant it back into the body where the defective cartilage is," said Benjamin Ma, MD, UCSF.

Coats had his surgery performed at Duke University has been pain free for more than a year.

"So far so good, no pain to walk, I can go up stairs," said Coats.

Dr. Ma is hopeful the clinical trial will yield positive results. The procedure is an alternative to microfracture, where surgeons create a hairline break in the damaged area -- and try to coax a scar tissue version of the cartilage to grow back. However Ma says the result rarely duplicates the joint's smooth articular cartilage.

"The two surfaces, when they rub together, are very, very smooth. Smoother than anything we can make with human hands, better than ceramic, better than metal, better than ball bearings, but that is what we're trying to duplicate," said Dr. MA.

He says the procedure takes about 10 weeks to complete, with several months of recovery time after that.

The replacement technique is designed to repair damage to an otherwise healthy knee, but not natural deterioration from age, commonly known as osteoarthritis.