Injectable goo could fix joints without surgery, early study suggests

Scientists have invented an injectable "goo" that can regrow cartilage in the body. For now, they've only tested it in sheep, but it could someday be used to repair joint damage in humans, the researchers say.

In particular, they hope the goo can treat damage caused by degenerative diseases, such as osteoarthritis, and Sports-related injuries, including anterior cruciate liGament (ACL) tears.

Cartilage is a strong, flexible tissue that lines the surface of joints, such as the knees. It cushions the joints and prevents the bones within them from grinding against one another during movement. But as we age, the cartilage in our joints gradually deteriorates. It can also become damaged by injury or as a result of chronic overuse. As the cartilage wears away, people may experience joint pain and struggle to walk.

"When cartilage becomes damaged or breaks down over time, it can have a great impact on people's overall health and mobility," co-study author Samuel Stupp, director of Northwestern University's Simpson Querrey Institute for BioNanotechnology, said in a statement. "The problem is that, in adult humans, cartilage does not have an inherent ability to heal."

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That's largely because cartilage doesn't have an active blood supply. As a result, surgery is often needed to repair damaged tissue.

One of the main treatments for cartilage damage is microfracture surgery. During this procedure, surgeons remove damaged cartilage and then create holes in the underlying bone. This enables blood containing specialized growth chemicals to flow into the area, which then triggers cartilage growth. However, often the cartilage that forms after this surgery — fibrocartilage — is weaker and less resistant to wear and tear than the cartilage normally found in joints, called hyaline cartilage.