A revolutionary way to mend damaged cartilage and bones by using a patient's own stemcells is being developed by scientists in an effort to speed up the repair process.

The University of Edinburgh researchers are developing therapy that would take stemcells from a patient's bone marrow and re culture it into bone or cartilage cells. The cells would then be placed in a "bioactive scaffold" made of a rigid mesh structure covered with molecules that benefit the cells. The scaffold would protect the stemcells and the molecules would stimulate their growth into bone or cartilage.

"We hope that this will kick-start the body's natural healing process es, enabling cells to grow and carry out repair to the damaged area,"researcher Dr Brendon Noble said.

The scientists believe there would be a number of circumstances where the therapy could be used including cartilage injuries orsevere fractures.

Results from an Australian trial released last week showed that stemcell therapy used to treat bone fractures was successful in all 10patients in the study. The small trial at Royal Melbourne Hospital onpatients who had non-healing long bone leg fractures injected partici pants with stemcells from their own bone marrow.

None of the patients had shown evidence of new bone formation in the months before the treatment and many were bed and wheelchairbound with debilitating fractures.

After the stemcell therapy, all 10 had new bone formation and seven had their long bone fractures healed over an average period of about five months. The higher the dose of the stemcells, the less time the fracture took to heal, with the median dose of stemcells implanted 14 per cent higher in patients whohad a union of their long bone.

Professor Silviu Itescu, founder of Mesoblast, the company that led the trial and has worldwide rights to the technology, said the results showed it was safe and effective forspeeding up bone fracture repair.

Standard treatment for patients with non-healing long bone frac tures is a bone graft where bone is harvested from the pelvis but this can lead to pain and infection. Some involved in the trial had already unsuccessfully tried bone graft treatment. "We've shown that at a minimum our procedure has elim inated that need for a bone graft procedure," Professor Itescu said.

Mesoblast will conduct bigger studies in the US and Australia , with the aim of developing a widely available treatment within four years.