15 novembre, 2006 16:07
Botox shots could help ease knee pain in osteoarthritis patients
Published: Wednesday, November 15, 2006 | 3:49 AM ET
Canadian Press
TORONTO (CP) - Those who suffer from severe knee pain may be able to get relief from Botox shots, suggests new research presented at the American College of Rheumatology's annual meeting this week in Washington.
Researchers at the University of Minnesota say the neurotoxin, widely known for its wrinkle-smoothing capabilities, may also be used to treat patients with severe to moderate osteoarthritis.
Some of the 37 patients involved in the six-month study were injected with Botox, while others were injected with a placebo.
After one month, the patients treated with Botox who suffered from severe pain showed a 28 per cent decrease in pain and a 25 per cent improvement in function. But the study found the injections had little effect on those with moderate pain. Two members of the placebo group dropped out of the study from lack of benefit at the end of the first month.
There will be a three-month assessment of the treatment in January and the trial is due to be completed in August.
Surgery has been the most common strategy to tackle knee pain in osteoarthritis sufferers, but researchers say Botox could be a good alternative for those who are too young, too old or too frail to go under the knife.
"Local joint treatment with injection could replace oral medications that carry the risk of systemic side effects, and may negate or delay the need for joint surgery," said Maren Mahowald, the study's main author and chief of rheumatology at the Minneapolis VA Medical Center.
"Much more research will be needed to determine the most effective and safe dose of toxin for the joint injections and the most appropriate dosing intervals," she added..
Botox, a purified form of Botulinum Toxin Type A, is best known as a cosmetic treatment for facial wrinkles. It's also used to treat excessive sweating and some neurologic conditions, according to WebMD, a medical information website. Botox is being studied as potential treatments for headache, overactive bladder and other ailments.
The study said there were no significant side effects related to the injections. Botox has been known to cause some muscle weakness when used for other treatments but since small doses are injected straight into the joint, not the muscle, that did not present a problem.
"This is an intriguing finding and Botox could have a role in patients who have risk factor or contraindications to knee surgery. And if it doesn't have side effects to knee strength, it would be very helpful," Dr. Shreyasee Amin, an assistant professor of medicine at the Mayo Clinic in Rochester, Minn., said in an interview with WebMD.
"It's too early to say for sure what role injections of Botox may play knee OA (osteoarthritis), but having the possibility of something that may alter the course or pain levels for a disease to which there is no known cure is exciting," Dr. Robert Wortmann, chairman of the University of Oklahoma's rheumatology department, told WebMD.
