St George researchers stand shoulder to shoulder over new discovery

RESEARCHERS at The St George Hospital have developed a simple yet revolutionary test for a common shoulder injury that will change the way such patients are diagnosed.

The four-part test - developed by Professors George Murrell and Judie Walton - was recently the subject of an article in the prestigious medical journal The Lancet.

The test involves a series of arm stretches, flexes and rotations to determine the likelihood of a tear in shoulder tendons known as a rotator cuff injury.

Prof Walton, of The St George Hospital's Orthopaedic Research Institute, said rotator cuff tears were responsible for approximately half of major shoulder problems.

"The most common symptoms of rotator cuff tear are shoulder pain, weakness and restricted shoulder movement, yet their diagnosis can be challenging even for experienced orthopaedic surgeons," Prof Walton explained.

"Rotator cuff tear is most common over the age of 60, when tissue starts to become more fragile."

Using this diagnostic test, The St George Hospital team's results are comparable in accuracy to those achieved by ultrasound and Magnetic Resonance Imaging (MRI) - a highly advanced three-dimensional x-ray machine - and should eliminate the need for some imaging tests in the future.

"The new clinical tests can be easily and conveniently performed by medical practitioners and other primary health care providers and should fast-track diagnosis of this shoulder injury - meaning patients are on their way to appropriate treatment much sooner," Prof Walton said.

For further information or to arrange photographs or interviews please contact Public Relations Officer, Victoria Civils-Wood, on 9350 2686.

April 12, 2001

TINY MOLECULE FOUND IN GIANTS OFFERS HOPE FOR MUSCLE CRAMPS

Muscle cramps - they're painful, often unexpected and there's not a lot that doctors can do to prevent or treat them.

But now a researcher with the Faculty of Medicine at the University of New South Wales based at St George Hospital in Sydney's south may have found a clue to helping us understand and deal with muscle cramps more effectively.

Associate Professor George Murrell from the Department of Orthopaedic Surgery at UNSW, in association with colleagues from the Hospital for Special Surgery in New York, studied the blood of players with the New York Giants Football team before and after they experienced severe generalised muscle cramps.

The researchers found that concentrations of a tiny messenger molecule, known as nitric oxide or NO, were three times greater after severe generalised muscle cramps.

Professor Murrell said the increase in NO was unexpected and contrasted with only small changes in thirty other blood tests performed on the players.

"The findings are very interesting and may help explain why people get muscle cramps. Eventually it might also assist us in preventing and treating cramps in both high performing athletes as well as in the elderly, tow groups commonly affected", said Professor Murrell.

Professor Murrell said the blood tests were carried out on the Giants at the start of their pre-season training. "The players trained twice a day in very humid conditions for four weeks. During the training 25 of the 77 players experienced such severe cramps that they required intravenous fluids. Blood tests were carried out on those 25 players and the results were compared with the earlier samples".

NO is one of the smallest molecules in the human body and has been found to be an important messenger in controlling blood pressure, uterus relaxation, erection and in memory.

The team's work will be published in the forthcoming edition of the American Journal of Sports Medicine and was awarded a 3M basic science award by the American Orthopaedic Society for Sports Medicine.

2/98
Date issued: Friday, 9 January 1998

Contact: Professor Murrell 02 9350 2827 or UNSW Media Liaison 9385 2873

Sports medicine specialists flex research muscle

Tendon healing with nitric oxide (NO), and gene therapy to repair bone and cartilage defects were amount the topics discussed by sports medicine experts at the inaugural Symposium on the Olympic Athlete (July 15-16; University of New South Wales, Sydney, Australia).

NO may modulate tendon healing, according to George Murrell (St George Hospital, Sydney). He found that NO synthase was activated 6 hours after surgical injury of rat Achilles tendons, and activity had increased five-fold after 7 days. The enzyme was not activated in uninjured tendons. Futhermore, rates fed the NO-Synthase inhibitor N-omega-nitro-L-arginine methylester, had a significant reduction in cross-sectional area (30% at day 7, p<0.01) and failure load or strength (24% at day 7, p<0.01) of the healing tendon. "If NO modulates tendon healing, then agents which spontaneously release NO might promote soft tissue healing", commented Murrell. Conversely, local inhibition of NO synthase may be useful to prevent unwanted healing responses.

Gerald Finerman (University of California at Los Angeles, CA, USA said the prospects for gene therapy to repair bone and cartilage defects are "very, very exciting". His team have harnessed the ability of bone morphogenetric protein (BMP), part of the transforming-growth-factor-B superfamily, to induce differentiation of mesenchymal cells such as osteoblasts and chondrocytes with BMP-2 resulted in the growth of a large pellet of articular cartilage after 8 weeks. Finerman said that, with this technique, bone-marrow cells, a more accessible and plentiful supply of cells, could be converted to cartilage-type cells for use a surgical implants.

Finerman concluded by noting that advances in diagnostic techniques and minimally invasive arthroscopic surgery had made the treatment of elite athletes a new discipline. These advances might speed rehabilitation and extend the careers of athletes who might otherwise retire early.

Arthur Papaloannou
Medical writer/Lancet correspondent

THE LANCET . Vol 352. July 25, 1998

Molecule cramps an athlete's style

By LEIGH DAYTON
Science Writer

The same molecule that aids everything from memory to erections has been linked to the excruciating muscle cramps that can temporarily cripple the fittest of professional athletes.

After studying blood taken from members of the New York Giants football team, an Australian physician and researcher and his colleagues in the United States suspect the chemical culprit driving muscle cramps is nitric, a stable byproduct of nitric oxide (NO), which is an important "messenger molecule" in the body.

Previously, experts knew that cramps were triggered by vigorous exercise, often in hot humid conditions , but had a poor understanding of what caused stressed muscles to contract suddenly into painful spasms, or cramps.

Endurance athletes, tennis players and rough-and-tumble footballers are ideal candidates for muscle cramps. Elderly people are also at risk of cramps, for reasons which are unclear.

"So the finding has potential clinical significance", said team leader Associate Professor George Murrell, of the University of New South Wales and St George Hospital.

He argued that if researchers could identify precisely the connections between NO and cramps, they could tailor treatments from NO-modifying drugs which are commercially available now.

Those medications are used to treat life-threatening septic shock, resulting from serious body-wide infection, and heart conditions like angina.

According to Professor Murrell, laboratory studies using rats and human muscles, removed during surgery, hint that the problem is one of "supply and demand" in which over-stressed muscles use up the available supply of NO, as well as running low on water, sodium, and adenosine triphosphate, a compound which stores energy.

In an upcoming journal article in the American Journal of Sports Medicine, Professor Murrell and his associates at Cornell University, New York's Hospital for Special Surgery (HSS) and the football team, will report biochemical evidence of mild dehydration and some muscle breakdown, during a serious muscle cramp. "The major findings, however, was a 300 per cent increase in nitric (during a cramp)". Professor Murrell said yesterday.

The research began while Professor Murrell was on a fellowship with the HSS that involved assisting the Giants' team physician. They conducted routine blood tests on the footballers at the start of their pre-session training, a four-week blitz in humid weather.

During training, 25 of the 77 players experienced severe cramps. The researchers collected blood samples of the cramp victims, and ran a battery of analytical tests which revealed NO's muscle-cramping style.

THE SYDNEY MORNING HERALD
SATURDAY, JANUARY 10, 1998