14 September 2000
The NHS could be spared thousands of pounds through a pioneering Action Research grant designed to improve the long term effectiveness of hip replacements.
The leading medical research charity, which is famous for its work in helping develop the first artificial hip surgery, has awarded researchers almost £30,000 to evaluate how much walking can wear down the hip joint. The results could help reduce the cost and pain of many secondary operations.
Some 50,000 people receive a hip replacement in the UK every year, of which 10% are secondary surgery.
Although research has been carried out into wear and tear during weight loading - when the foot is on the ground - there’s been little attention given in to the ‘swing phase’ of walking, when the foot is off the ground.
In the one-year project, a team of experts at both the University of Leeds and the city’s General Infirmary will be researching ways in which the ball and socket of an artificial hip undergo a tiny separation (0.5 - 1mm) during the swing phase movement, causing a likely accelerated wear of the socket.
Professor John Fisher, of the University of Leeds, explains: ‘More than 1% of the population benefit from hip replacements, the lifetime of which is determined by the amount of ‘wear’ imposed on them.
‘High wear can cause failure of the hip joint after 10 to 20 years, and this remains a major concern - particularly for younger patients with osteoarthritis who require hip replacement surgery. ’
Surgical materials can cost up to £1,000, with the actual operation setting the health service back another £5,000. The cost of a revised operation can be double this amount, meaning the long term performance of initial surgery is vital.
The researchers, based at the University’s School of Mechanical Engineering and the Department of Microbiology, and Infirmary’s Department of Orthopaedic Surgery, will utilise specially-created hip joint simulators in their laboratory. It is hoped the findings will shed light on the benefit of different materials, and lead to recommendations to improve surgical techniques or design.
Action Research, the UK’s leading medical research charity, pioneered artificial hip joint surgery in the1960s, and has continued to fund projects to increase the life-expectancy of hip joints.
A booklet produced by the charity, entitled The Hip Operation: What you need to know, is designed to give patients an insight into what to expect from such surgery. For a copy, send a £2.50 cheque payable to Action Research, Vincent House, North Parade, Horsham, West Sussex, RH12 2DP.
Action Research launched its Touching Lives campaign this year, which aims to raise £1.5m for vital medical research to benefit children and families across the UK. Visit the charity’s newly-launched website at www.action.org.uk
Fact file: *Osteoarthritis is the most common reason for having an artificial hip, but people with rheumatoid arthritis, osteoporosis or some physical injury to the hip may also benefit from a new joint. *Since hip replacement surgery began, a wide range of joints have been produced using a variety of different materials including cement. *The researchers will mimic the micro separation of the ball and socket during 10 million cycles, stopping every one million cycle to examine the wear and tear.
For further media information, photographs and interview opportunities, please contact Nicole Duckworth in the Action Research press office on 01403 327403.