Patients could grow new joints, shows rabbit study

PEOPLE with knee or hip problems could in future “grow” their own replacement joints using their own stem cells, scientists said.

A team of experts has, for the first time, shown it is possible to grow joints inside the body which have a full range of movement and can bear weight.

The joints could potentially last longer than commonly used artificial joints, saving elderly patients from having to undergo gruelling operations to replace those that have worn away.

The pioneering study was carried out on rabbits but researchers believe it paves the way for a future where people grow their own bone and cartilage.

Professor Jeremy Mao and his team at Columbia University Medical Centre in New York led the study with colleagues from the University of Missouri and Clemson University.

They used a computer to help create artificial scaffolds anatomically the same size and shape as rabbit hip joints. The scaffolds were infused with a growth factor and implanted into 10 rabbits after their own hip joints had been removed.

Attracted by the growth factor, their own stem cells went to the location of the missing joint and regenerated cartilage and bone in two separate layers.

Just three to four weeks after surgery, the rabbits had fully regained movement and could bear weight similar to animals who had never undergone surgery.

The rabbits had grown their own joints using their own stem cells instead of relying on an injection of stem cells into their body.

The study was published online in The Lancet medical journal.

Prof Mao said: “In patients who need the knee, shoulder, hip or finger joints regenerated, the rabbit model provides a proof of principle. Several scientific and regulatory issues must be dealt with prior to patient applications.”

In an accompanying comment article, Dr Patrick Warnke from Bond University in Australia, said today’s research offered a “promising insight” into the future for patients.

However, he warned not everyone would have the same capacity for natural regeneration, for example elderly people with diabetes may not react as positively.