Archive for November, 2012
Osteoarthritis is far more common in individuals with a history of traumatic joint injury. This is why athletes often develop osteoarthritis of the knee later in life. It is important to distinguish between the normal wear of exercise and the accumulation of small injuries. Healthy work-outs do not increase the risk of osteoarthritis, but those who push their joints beyond their limits may cause long-term injuries.
Recent work by Dr. Cruz of the University of Guelph examines the progression from a single traumatic event to the development of osteoarthritis. Dr. Cruz specifically wanted to know if damage to cartilage, bone, or both, led to more severe symptoms after the immediate healing had been completed. This research showed that even after a therapeutic exercise regimen, damage to cartilage and bone did not heal. This means that severe, single-event injuries may have long-term effects, even after immediate treatment.
This is important because it means that some knee pain may not heal naturally. Damage to cartilage and bone may kill the blood supply to an area and eliminate its potential for healing. If you have a severe knee injury, it may not be enough to wait for the swelling and pain to subside. Consult your physician and check if more serious treatment may be necessary.
A risk factor is a description of a characteristic of a group that is prone to a particular disease or disorder. Having one or more risk factors does not guarantee the presence of the disease, and their absence does not ensure good health. The identification of risk factors is important because it can identify traits or groups of individuals that are at elevated risk, and so require more frequent and more thorough examination.
Women and the elderly are at higher risk of developing osteoarthritis. Other well known risk factors include poor diet, inactivity, prior joint injury, and a family history of osteoarthritis. Recent research by a Harvard Medical School professor, Dr. Losina, suggests that ethnicity may also be related to osteoarthritis risk. Dr. Losina found that female minorities were at higher risk for osteoarthritis than caucasian females. Further, female minorities with osteoarthritis were more likely to need joint replacement surgery.
These are not absolutes. Many individuals with all risk factors never develop osteoarthritis. There are many risk factors that are beyond your control, like age, ethnicity, family history, and gender. But if you are at elevated risk of developing osteoarthritis because of poor nutrition or lack of exercise, it’s time to change your habits. It might even save you from surgery.
Knee osteoarthritis is commonly treated by medications, diets, exercise, braces, and surgery (among other things). Most medications for osteoarthritis reduce pain and inflammation. This can indirectly slow the progression of the disease by reducing the fluid in the joint-space (and thereby reducing the pressure on the cartilage). A new drug, strontium ranelate, delays progression of osteoarthritis by as much as 40%, without employing anti-inflammatories. This is important because it could potentially be taken in combination with more conventional medications for even more effective treatment.
A recent study presented at the American College of Rheumatology examined the progression of osteoarthritis in more than 1300 seniors over 3 years. They found that those taking strontium ranelate were 30-40% less likely to require surgery for their osteoarthritis than people taking a placebo.
Strontium ranelate has been approved in Europe, but has not yet been accepted by the FDA. If the results of this recent study are validated by other papers, US approval should be on the horizon. So keep your ears open, and when strontium ranelate hits American markets ask your doctor if it could help you.
Osteoarthritis is often considered to be a degeneration of cartilage purely due to accumulated wear and tear. This is not entirely accurate. If wear and tear accelerated the deterioration of cartilage in the knee, then all exercise would be harmful. In fact, exercise has been shown to be highly beneficial to individuals with osteoarthritis of the knee.
As explained by Dr. Hersh, Ph.D., M.D., osteoarthritis of the knee is more closely linked to synovitis (inflammation of the joint space). The inflammation holds extra fluid in the joint space, which increases the pressure on the cartilage, and so greatly increases the friction of the joint. Since friction leads to rapid degradation of the articular cartilage, this synovitis makes osteoarthritis much worse. Understanding the role of synovitis in the progression of osteoarthritis is important for two reasons:
1: Synovitis can be helped by exercise, which can drive fluid out of the joint space.
2: Treating synovitis can effectively treat osteoarthritis.
This means that exercise can treat osteoarthritis in two ways:
1: By helping you to lose weight, which reduces the pressure felt by the cartilage of your joints.
2: By reducing your synovitis, which reduces both pressure and friction in the joint space.
So get out there and exercise. Your discomfort today will save you far more pain tomorrow.
The 2012 Nobel Prize in Physiology or Medicine was awarded to researchers who developed induced pluripotent stem-cells (IPS-cells). IPS-cells do not carry the ethical stigma of embryonic stem cells, since they can be created by coaxing mature skin cells (from consenting adults) into their developmentally flexible states. Most importantly, they offer the opportunity to externally grow healthy living tissue as needed. So far, IPS-cells can be grown into relatively simplistic cells (like cartilage and bone), and not into more complex tissues like livers or kidneys.
Researchers at Duke University have recently developed a new technique to grow IPS-cells into cartilage. This technique could permit a limitless production of cartilage for researching drug treatment. Short term (within the next 3-5 years), cartilage from IPS-cells might be sophisticated enough for implantation. This could delay a knee replacement by several years, and dramatically improve quality of life.
Understanding the relevance of things like IPS-cells matters because it reminds us of the importance of scientific development. One of the recipients of this Nobel Prize earned it by turning a frog back into a tadpole. While this may seem far from the daily knee pain felt by those suffering from knee osteoarthritis, it is his research that will lead us to the artificial cartilage that may cure them.
This post has been delayed by a hurricane, inspired by a spooky holiday, and grounded in science:
While osteoarthritis does not carry a terrifying death-sentence like severe cancers, it can still produce fear. Osteoarthritis of the knee can lead to extreme pain during physical activity. This pain can lead to apprehension about exercise. Ultimately, that apprehension can become so severe that activity is avoided. This can be catastrophic.
A recent article in Arthritis Care & Research studied predictors for treatment success. The authors examined numerous factors including age, BMI, surgical history, and physical therapy treatments. After their exhaustive review, they found only 2 factors were directly linked to the outcome of the treatment: Knee instability, and fear of physical activity.
This means that the negative effects of being scared of exercise may be equivalent to damaged ligaments, muscles, and menisci. In other words, the psychological effects of fear are as dangerous to your health as the physical effects of injury.
So if the thought of exercise makes you nervous, even if you know that it will bring you pain, do not let your fear make you unhealthy. Work through it now, and overcome your fear. It will help you later.