The jelly made from stem cells that can mend your wobbly knees

Doctors are using a type of jelly made from stem cells to treat arthritic knees. The stem cells, which are extracted from donated umbilical cord blood, appear to trigger the repair and re-growth of damaged cartilage.
A small study found the one-off treatment led to a 67 per cent improvement in cartilage repair, and researchers believe it could become an alternative to joint replacement surgery. Two clinical trials are under way assessing its effects.
Cartilage acts as a shock absorber in the joint, and provides a smooth surface that allows the bones to glide smoothly over each other. However, this layer can break down with age-related wear and tear, triggering pain and swelling — a condition known as osteoarthritis.

The stem cells are extracted from donated umbilical cord blood

Once damaged, joint cartilage does not renew itself as easily as other tissues, as it is poorly supplied with blood vessels and nerves. Current treatments include painkillers, physiotherapy and steroids — or partial or total knee replacement. Around 40,000 of these procedures are carried out every year, but the hope is that stem cells may reduce this.

Stem cells are like blank slates, and can turn into a variety of different cells in the body. There are some stem cells found naturally in the knee, and while these can turn into cartilage cells, their number reduces with age and they become less efficient, so cannot cope with the damage. To overcome this, scientists extract stem cells from the knee, then increase their numbers in a lab before implanting them back into the knee. 
However, this requires extraction and implantation, and due to the limited number of stem cells available, it seems only to repair small areas of damage.
The latest treatment is based on stem cells from donated umbilical cord blood. These are much more active than adult stem cells, and animal studies suggest they are better at producing cartilage.
The blood is collected by the NHS Cord Blood bank — usually umbilical cords are discarded after birth, but some mothers agree to donate them in order to help others. Stem cells are removed from the blood then grown in a lab and turned into a gel-like material — the orthopaedic surgeon uses keyhole surgery techniques to put the gel into the damaged area. 

The treatment could be particularly suited to older patients as their own stem cell reserve is depleted

Researchers say this could be particularly suited to older patients (as their own stem cell reserve is depleted), as well as those with large areas of damage.
Following an early, small study involving ten patients in Seoul, there are now two trials under way with 50 people at Rush University in Chicago, and Brigham and Women’s Hospital, Massachusetts, and at seven hospitals in Korea.
Professor Alan Silman, Medical Director of Arthritis Research UK, said: ‘Using stem cells from various sources to regenerate cartilage has huge potential.
‘The debate is whether to use an adult individual’s stem cells or to take advantage of the more widely available embryonic stem cells such as those in an umbilical cord. There are advantages and disadvantages to both approaches.
‘Although the technology is still some way off being available for routine use, this is an area of research with substantial activity and could provide an alternative to surgical joint replacement in the future.’