Researchers have shown it is possible to grow properly working joints inside the body using a patient’s own stem cells, after damaged bone has been removed. They say the joints will have a full range of movement, be able to bear weight and may even last longer than the current generation of artificial devices. That would save patients from repeat surgery after their original hip or knee replacement, which usually last 15-20 years, has worn out.
An embryonic stem cell which could help people with knee or hip problems ‘grow’ their own replacement joints An American team carried out a pioneering study on rabbits and believes it paves the way for a future where people can grow bone and cartilage inside their own bodies. They used a computer to help create artificial frames that were the same size and shape as rabbit hip joints.
These frames were infused with a growth hormone and implanted into 10 rabbits after the animals’ hip joints had been removed. Attracted by the growth hormone, the rabbits’ own stem cells went to the location of the missing joint and regenerated cartilage and bone in two separate layers.
Just 3 to 4 weeks after surgery, the rabbits had fully regained movement and could bear weight similar to animals that had never undergone surgery, according to the study published online in The Lancet medical journal. The rabbits had grown the joints using their stem cells, instead of relying on an injection of stem cells into their body.
This is the first time scientists have regenerated a complete limb joint using either harvested stem cells or an animal’s own stem cells. Previously scientists have grown ’spare part tissue’ in the laboratory from patients’ stem cells for use in repairing diseased organs, including heart valves and bladders.
Lead researcher Professor Jeremy Mao of New York’s Columbia University, said: ‘This is the 1st time an entire joint surface was regenerated with return of functions including-weight bearing and locomotion. ‘In patients who need the knee, shoulder, hip or finger joints regenerated, the rabbit model provides a proof of principle.’
But humans could be more challenging as they have only two legs to bear weight. Dr Patrick Warnke from Bond University in Australia said the research offered a ‘promising insight’ into what might happen in the future for patients. A person would also be immobile for a considerable period of time while their new joint grows, he said.
Scientists at Leeds University are also developing a similar treatment and say small replacement body parts, such as patches to repair clogged arteries, could be routinely grown by 2015. But … it may take 20-30 years to develop the more advanced techniques. (HWM and Laura Hope, Daily Mail)