Sporty Mary is pain-free after new knee treatment Surgeons have had limited success in repairing cartilage or stimulating its growth. Microfracture, for example, in which small holes are created in the bone to encourage growth, does not always have long-lasting results, while techniques to grow cartilage cells in a laboratory followed by a knee transplant are costly and expensive. The new procedure, called BioPoly, uses an implant made from hyaluronic acid - a natural lubricant produced by joints - and a form of the plastic polyethylene. This creates a flexible yet strong material which, surgeons think, will mimic normal cartilage and protect the ends of joints. Dinesh Nathwani, a consultant orthopaedic surgeon at the London Clinic who took part in the trial, says the new implant is not suitable for everyone and would benefit younger and middle-aged patients most. "This implant has minimal interference with the bone structure," he says. Patients can weight-bear almost immediately after surgery, compared to several weeks of enforced rest for other procedures. Yet given recent concerns over hip and knee implants, people may have reservations about this new procedure. Mr Nathwani says that the 35 patients in the trial - approved by a UK ethics committee - will be carefully monitored for five years, so any problems should be identified early. Marcus Green, orthopaedic consultant at the BMI Priory Hospital in Birmingham, says that though the new implant looks exciting, "it is not a miracle cure for arthritis." Keal, who had the implant inserted earlier this year at the London Clinic, is so far delighted with the result. I'm back exercising in the gym again for the first time in years, I don't take any pain killers, and I can wear high heels. I've even booked myself on a skiing holiday next year.