Hip and knee treatments pioneered in Oxford

The number of hip replacements which fail because they are poorly designed should be cut following pioneering research by scientists at the Department of Engineering Science and the Nuffield Orthopaedic Centre. A team led by Professor John O'Connor (pictured left), Professor of Engineering Science, and orthopaedic surgeon Mr David Murray, has developed a new system for screening hip replacements before they go on the market. Supported by funding from the Arthritis Research Campaign, the team is using stereo X-rays to measure how a joint implant moves relative to the supporting bone, in 3D, with an accuracy of a few tenths of a metre. This Roentgen Stereophotogrammetric Analysis technique is providing major insights into how implants function, and why they may fail in the longer term. The team is now building a database to compare new types of implants. Mr Murray said: `Every year around 50,000 people in the UK will have a hip replacement. There are currently more than 60 different types of total hip replacement on the market in the UK, and many new ones are being introduced each year. By developing a system to screen new types before they are released, we hope to avoid public concern when, as has happened, one particular type fails.' The Oxford team is also investigating ways of restoring normal knee movement after knee replacement surgery; testing the movement of the elbow joint, with the long-term goal of designing better surgical replacements; and trying to explain the reasons for the failure of surgery to correct foot deformities. Mr Murray and the joint replacement surgeons at Oxford have now developed a technique for implanting the Oxford Knee, developed by Professor O'Connor and orthopaedic surgeon Mr John Goodfellow, requiring only a small incision. Professor O'Connor said: `This is likely to represent a substantial advance in knee replacement surgery. Patients should recover far more rapidly so the procedures could be done as a day case. Post-operative pain should also be minimised and complications less frequent and less severe.' Around 30,000 people a year in the UK have artificial knee joints inserted, and 10,000 undergo surgery to replace their elbow, shoulder, or the knuckles in their hands.