New Approaches for Osteoarthritis
It is now clear that osteoarthritis is much more than wear of joint cartilage. Arthritis Foundation-supported research has made great progress in understanding how metabolic factors, particularly those associated with obesity, contribute to osteoarthritis.
In these studies, inflammatory cytokines produced by fat cells have been shown to alter the behavior of the cells in articular cartilage in ways that set osteoarthritis in motion. New studies have demonstrated that leptin, which is produced by fat cells, may have a role in promoting osteoarthritis. Investigators found that mice unable to respond to leptin are resistant to osteoarthritis.
One of the great needs in osteoarthritis is to gain an understanding of why joints damaged by the disease become painful. Joint cartilage does not have nerve endings and therefore cannot be the source of joint pain. To answer this question, Arthritis Foundation-funded investigators carried out a careful analysis of joint X-rays and correlated them with symptoms among patients with osteoarthritis.This study demonstrated how different radiographic findings correlate with pain in the knees of patients with osteoarthritis. Although researchers continue to search for information about how osteoarthritis leads to pain in joints, this study helps narrow the search.
The importance of treatment in the early stages of osteoarthritis also came to the forefront this year. According to Dr. John Hardin, Arthritis Foundation, vice president of research, "These earliest stages of the disease are critical because much of what causes damage happens in the first few months following an injury."
- A Rush University Medical Center study suggested that medications blocking inflammation may slow or stop progression of osteoarthritis if applied early.
- A Yale University Medical School study looked at ways to predict which patients would be most likely to benefit from an arthroscopic partial meniscetomy operation in the early early stages of osteoarthritis. While a large-scale clinical trial is needed to address this question deifinitively, the study showed that individuals with a displaced tear, locking, increased pain and no bone marrow lesions were most likely to benefit from the procedure.
The Arthritis Foundation continued to suport the work of the Osteoarthritis Research International (OARSI). As part of the organization's Osteoarthritis Biomarkers Global Initiative, a workshop held in April 2009 enabled doctors and researchers to explore the application of biomarkers to clinical trials, analysis methods, commercialization of biomarkers and goals for the future.
With more than 1,000 members, from more than 50 countries, OARSI is integral to spreading the concepts, hypothesis and developments concerning osteoarthritis among the international community. The Arthritis Foundation also continued support of the Siegal North American Osteoarthritis Workshop. In October 2009, the third annual SNOW brought together researchers from the United States, Canada, Sweden, Great Britain and Denmark to focus on post-traumatic arthritis of the knee as a model for the study of osteoarthritis.
In a keynote address, Dr. Stefan Lohmander, MD, PhD, suggested that more than half of individuals who tear the anterior cruciate ligament will go on to develop osteoarthritis, usually within 10 to 15 years of their injury, and that all types of joint injury predispose a patient to the premature development of disease.
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