Knee pain generally comes from the progressive wear and tear of cartilage known as osteoarthritis, which affects nearly one in six adults – 867 million people – worldwide.

Mechanical testing reveals that the newly developed hydrogel – a material made of water-absorbing polymers – can be pressed and pulled with more force than natural cartilage, and is three times more resistant to wear and tear.

Implants made of the material are currently being developed by Sparta Biomedical and tested in sheep before clinical trials in humans next year.

The researchers took thin sheets of cellulose fibres and infused them with a polymer called polyvinyl alcohol – a viscous goo consisting of stringy chains of repeating molecules—to form a gel.

Image credit: Benjamin Wiley, Duke University

The cellulose fibres...