Mayo Clinic seeks adults who are age 40 or older and have knee pain that has not responded to medicines, exercise or physical therapy for a research study. The purpose of this research study is to find out what effects (good and bad) the botulinum toxin (Botox) has on patients with knee arthritis. Eligible participants will have been diagnosed with knee arthritis that can be confirmed by x-ray.
Botulinum toxin has been approved by the U.S. Food and Drug Administration (FDA) for use for other conditions, including migraine, muscle spasm and wrinkles, but not for knee pain. Osteoarthritis, sometimes called degenerative joint disease or osteoarthrosis, is the most common form of arthritis. Osteoarthritis is characterized by the breakdown of joint cartilage and may affect any joint in your body, including those in your fingers, hips, knees, lower back and feet. Knee arthritis typically affects patients over 40 years of age.
“It is well known that Botox has a potent effect on muscle, causing temporary paralysis and leading to its widespread use for various medical and cosmetic conditions. There is now some evidence in animal and laboratory studies that Botox affects the sensory nerve endings that carry pain messages to the brain. Initial use in humans has suggested Botox may be effective at treating pain related to osteoarthritis” says Andrea Boon, M.D., a Mayo Clinic physician and lead researcher for the study. “As yet, this effect of Botox has not been formally studied, but if found to be effective in this initial study in patients with knee arthritis, this could be an excellent second line therapy for patients who no longer respond to cortisone injections for their pain but are not ready to have joint replacement surgery.”
Qualified participants will be put in one of three groups by chance. One group will get a knee injection with cortisone, and the other two groups will get a knee injection with botulinum toxin (either high dose or low dose).