The first sign is often a twinge in your back or some stiffness at the base of your thumb. Or maybe you're getting out of the car and a sharp pain shoots down your leg from your hip to your calf. Nothing serious, you think. I must have just strained something. I'm too young to have arthritis. Think again. If you are within even shouting distance of middle age, chances are you have osteoarthritis, a degenerative disorder in which the cartilage the natural shock absorber that cushions the insides of your joints begins to break down Doctors used to think of it as a disease of old age, but they now believe that this form of arthritis, the most common of about 100 types, begins its relentless, initially painless course when you're still in your 30s, 20s or even younger. Most of the time you won't suspect anything is wrong until you're in your 40s or 50s and begin to feel those telltale twinges, signs that the disorder may be starting to affect your bones. By then the damage has been done, and even the best treatments can't do much more than ease the pain and try to maintain the status quo in what are already degenerating joints.
The situation with arthritis is about to get worse, a lot worse, and very soon. It's almost as if we were watching the formation of an epidemiological perfect storm. Across
In the
What's more, many would be patients don't know that something can or needs to be done, or they don't have enough information to make an informed (and safe) decision about their care. Arthritis is a huge problem in our society, says Dr. Koh Wei Howe, president of
There exists, however, the possibility of some relief amid all the aches and pains. Researchers are paying a lot more attention to osteoarthritis these days. They have discovered that what they thought was a fairly straightforward mechanical breakdown of the joints is a much more complicated process with lots of component parts. Although this means that patients hoping for a quick fix are likely to be disappointed, scientists are starting to gain the kind of insights that can lead to more effective treatments and better strategies for heading off trouble before it begins.
How complex a process are we talking about? Doctors used to think that cartilage was the beginning, middle and end of the osteoarthritis story. Now they know that cartilage is important, but so is everything that surrounds it, muscles, bones, tendons and ligaments. The damage caused by wearing ill-fitting shoes, suffering a football injury or spending day after day stooped over in a field can certainly give rise to arthritic joints. But the worst problems often stem from basic differences in the body's biochemical makeup. For example, some people's cartilage seems to resist damage better than others.
In addition researchers have discovered an array of biochemical messages that are traded between bones, muscles and other parts of the body and play a key role in keeping joints healthy. Ultimately, we think it's the biochemical approach that's going to solve the riddle of arthritis, says Dr. Mitchell Sheinkop, an orthopedic surgeon at the Rush Presbyterian St. Luke's
Until then, what doctors would like to have is some kind of test that will identify people in the earliest stages of osteoarthritis before too much damage has occurred. That way their treatments might stand a better chance of arresting the degenerative process before disability sets in. Unfortunately, conventional X rays, which give very detailed pictures of bone, don't provide very good images of cartilage. And researchers haven't yet discovered any biological markers in the blood that reliably tell them, Hey, this person's cartilage is starting to fall apart. Do something!
To understand the latest insights and where they might be leading, it helps to know a little bit about how a joint is put together, and there's no better place to start than with the cartilage. Like so many tissues in-the body, cartilage is composed mostly of water. Indeed, you can think of it as a damp sponge. The spongy part contains several important components, including the chondrocytes cells that generate new bits of cartilage and various molecules that give the sponge its structure and help hold it together.
With every step we take, our moving body puts pressure roughly equal to three times our weight on the knees and hips. As that pressure is distributed across those joints, cartilage is compressed, absorbing most of the load. And, as you might expect with something that resembles a damp sponge, water is squeezed out of the cartilage into the space between the bones. Once the pressure is released, the water flows back into the cartilage, carrying with it nutrients that were picked up from the synovial fluid, which fills the joint. This constant fluid exchange is critical to maintaining healthy, pliable cartilage and explains why joint moving exercises such as walking help delay the progress of osteoarthritis.
Sometime between ages 40 and 55, the activity of the chondrocytes starts slowing down and the cartilage takes longer and longer to replenish itself. As the cushion of cartilage grows progressively thinner, the bones begin to grind against one another. This is a normal consequence of aging, but aging isn't the only culprit. Something as simple as falling on an icy sidewalk or putting on some extra weight can increase your risk of osteoarthritis. Anything that puts extra stress onto the joints will wear out the cartilage that much faster.
Now the first wrinkle: It appears that not all cartilage is created equal, says Dr. Roland Moskowitz, president of the Osteoarthritis Research Society International in
Some evidence for this comes from related research on bones. Most people think of bones as inert objects whose only job is to keep our bodies from collapsing into a puddle of flesh. But bones are actually quite active tissues, constantly building and rebuilding themselves from the inside out. If you break a bone, the body produces repair proteins that direct cellular activities as the bone knits itself together. When investigators take these so-called osteogenic proteins and sprinkle them on lab samples of damaged cartilage, the cartilage begins to repair itself. Now here comes the interesting part, says Dr. Klaus Kuettner, professor of biochemistry at Rush-Presbyterian-St. Luke's. The ankle joint responds better than the knee joint to osteogenic proteins. Is that why the ankle rarely gets osteoarthritis? We don't know, he says, but it's a hint in that direction.
Another hint comes from the observation that women with strong, healthy bones the kind least susceptible to the brittleness of osteoporosis are at greater risk of developing osteoarthritis. Again, doctors suspect a complex interplay of mechanical and biochemical factors. Healthy bones can support heavier loads. They also tend to replace old bone cells with new bone cells at a pretty fast clip. But somehow the biochemical signals responsible for the bone's increasing turnover rate trigger even greater damage to the cartilage. Or is it the other way around? Is it damaged cartilage that gets the process started by sending aberrant signals to the bone? At this point, it would be a mistake to fight bitterly over whether osteoarthritis starts in the bones or cartilage, because in the end there maybe different forms of the disease, says Dr. Bjorn Olsen, a cell biologist at
In a 10 year study of American families that include members who have developed osteoarthritis in their 40s and 50s, Olsen's group has identified at least three genetic variations that make the cartilage of these patients more susceptible to overloading. Other scientists have found at least a dozen cartilage-disrupting enzymes that appear to be overactive in osteoarthritis. Yet even the interaction between bones and cartilage doesn't tell the whole story. You also need to take into account the ligaments those tough bands of tissue that connect bones to bones and the muscles that surround and stabilize the joints. Ligaments can get stretched or torn, and muscles can atrophy from underuse, disrupting a joint's finely tuned mechanism.
Take, for example, the quadriceps, the large muscles on the front of the thighs that help raise and lower the legs. It's common knowledge that patients with osteoarthritis of the knee will have weakness in the quadriceps, says Dr. Kenneth Brandt, a rheumatologist at
It makes sense. The stronger the muscles, the greater the load they take off the joint, thus limiting damage to the cartilage. Brandt's group is trying to determine whether healthy seniors who strengthen their quads by doing exercises with elastic bands can delay, or possibly prevent, the disabling consequences of osteoarthritis in their knees. Professor Mohd Farooque, former head of orthopedics at the All India Institute of Medical Sciences in
However the arthritic process gets started, the damage to the joint eventually begins to grow. That's when the body's immune system gets into the act. White blood cells rush into the joint and release destructive proteins that chew up the pieces of damaged tissue. This so-called inflammatory process, which is often but not necessarily accompanied by swelling, works well when the body needs to fend off an acute attack, say, from invading viruses or bacteria. But when the problem is chronic, as in osteoarthritis, the white blood cells might overreact, repeatedly releasing so many mopping up proteins that even healthy tissue is laid waste. In rheumatoid arthritis, the immune-system response is particularly aggressive.
So what can you do? The first step for most patients is to try to get some immediate relief. About 15% don't seem to experience inflammation; for them, over the counter painkillers like acetaminophen (Tylenol) are often all that's necessary to control their symptoms. Things become more complicated when inflammation is involved. Western standbys like aspirin or ibuprofen are pretty good anti inflammatories, but long-term use can trigger dangerous side effects such as internal bleeding. Traditional remedies abound as well: acupuncture, massage, hot-spring baths, herbal ointments and more targeted (and dubious) palliatives such as sour plum juice (in
Some researchers believe there is too much emphasis on drug treatments for osteoarthritis. There are other things that can improve symptoms as much as pills, says
Sometimes surgery is unavoidable. Each year doctors in the
No single approach works best for everyone. As with any chronic condition, there are always some things you can't control. But there's still a lot you can do for yourself. That's the lesson Kazuko Hayashi, a 71 year old housewife from the city of
The Other Crippling Joint Disease
As debilitating as osteoarthritis can be, it at least develops gradually. That may not seem like much consolation until you consider the other arthritis rheumatoid arthritis (RA) which in severe cases hits like a freight train. People who are jogging one day," says Dr. Stanley Cohen of Dallas'
Although the symptoms can be similar, the diseases are very different. Osteoarthritis is focused on a particular joint; RA is a systemic disease,an autoimmune disorder in which the body's defense system attacks the joints through the thin layer of cells called the synovium that line and lubricate the joints. The runaway immune response clogs the synovium with infection-fighting cells that release proteins called cytokines. These are compounds that fuel inflammation. The synovium becomes engorged with new blood vessels and begins to grow, kudzu-like, penetrating and further damaging cartilage and bone.
The most visible symptoms of RA are swollen joints and crippling stiffness, particularly of the hands and feet. It can cause fatigue, fever and loss of appetite. It can also affect the heart and lungs and their surrounding membranes. The disease, which afflicts 2.5 million people in the
When RA was given its name in the 19th century, those who suffered from it including impressionist master Pierre-Auguste Renoir had little to look forward to beyond life in a wheelchair. Even in the 1950s, says Cohen, few treatments were available other than aspirin or cortisone, a powerful anti-inflammatory with severe side effects when used at high dosages. Injections of gold salts also provided some relief, although no one really knew why.
Prospects have improved dramatically especially, says Cohen, if we treat early and we treat aggressively. Dr. Anand Malaviya,
Today the most effective treatments are combination therapies. Methotrexate, a cancer drug that has been used to treat RA for 30 years, is augmented by other drugs, including the new but costly biologies such as etanercept (Enbrel), infliximab (Remicade) or anakinra (Kineret). These are genetically engineered versions of naturally occurring molecules that bind or block the activity of cytokines. Also in early development are drugs designed to reduce the formation of the blood vessels that feed the growth of the synovium.
Researchers have discovered a genetic marker that is often associated with RA's earliest onset and most severe cases. Yet not all RA sufferers have the marker (and vice versa), which makes scientists wonder whether RA is a single disease. Environmental factors might also play a role, although no one knows whether the trigger is a virus, a bacterium or something else. Autoimmune diseases are always tricky. But even if RA doesn't yield to a simple fix, it is becoming easier to manage for those who can get proper treatment.
A HOST OF CULPRIT
CARTILAGE
Made up of water, proteins and sugars, cartilage is the body's shock absorber. Injury, age and many other factors can cause cartilage to break down, but the end result is the same: without its cushion, bones start to grind against one another
MUSCLES
These support the joints. The quadriceps, for example, are responsible for holding up the knee and relieving some of the stress of walking and running. Weak quads can put too much strain onto the joint, leading to tears in the tendons
BONE
While bone normally responds to eroding cartilage by sending out spurs and other odd growths, sometimes it's the other way around: changes in bone structure that affect the shape of a joint can trigger a breakdown in the cartilage
TENDONS AND LIGAMENTS:
By connecting and anchoring muscles and bones, these provide support for the joint. If they are torn in an injury or weakened from lack of use, the cartilage in the knee is forced to bear more weight, hastening its collapse.
INFLAMMATION
As cartilage degrades, immune cells swoop in to engulf and destroy the dying tissue. In their zeal, they even attack healthy tissue. The debris, including toxic enzymes, can build up in the fluid of the joint, causing painful swelling
GENES
More than half of arthritis sufferers are born with mutations in their genes that control cartilage formation and destruction. These aberrations can result in cartilage that is weaker to begin with or that degrades faster than it should
WHAT YOU CAN DO
you don't have to suffer. There are many ways to find relief
DRUGS
There is still no cure for arthritis, but many medications can relieve the pain in stiff joints.
1. Over the counter painkillers
For mild pain, acetaminophen should be your first choice, as it relieves discomfort without damaging the digestive tract. If pain persists, your doctor might recommend aspirin or ibuprofen, which can reduce the swelling and damage due to inflammation; anti-inflammatory drugs, however, can be harsh on the stomach
2. Cox-2 inhibitors
These newer analgesics tend to cause fewer stomach problems than traditional anti inflammatories. But they are expensive, and recent studies have linked them to heart problems
3. Tetracylines
These antibiotics were designed to kill germs, but they can also slow erosion of the cartilage
4. Hyaluronic acid
Injections of this natural lubricant, particularly in the knee, can ease pain for as long as a year
5. Corticosteroids
Shots of steroids, which reduce inflammation, can provide a short-term fix for joint pain. Continued injections, however, can worsen a damaged joint by masking discomfort and enabling you to continue destructive activities. Because their pain is limited to specific joints, osteoarthritis sufferers don't need the wider ranging effects of corticosteroid pills
SURGERY
If pain persists, surgery can either relieve the pressure on joints or replace them altogether.
1. Arthroscopy
In this minimally invasive procedure, doctors clear away dying cartilage and smooth out rough joint connections through slit-size incisions. A recent study suggested that in some cases, arthroscopic surgery was no better than sham surgery it seems to work best when the joint is still mechanically sound
2. Bone fusion
Fusing bones together with pins or plates can eliminate the pain caused by a badly damaged joint; the joint, however, will never bend again
3. Joint replacement
When the bones in a joint are damaged beyond repair, a substitute joint can in some cases be fashioned out of plastic or metal. Total hip replacement is the most common, but almost any joint, including the knee, thumb, elbow and shoulder, can be replaced
4. Tissue repair
Failing joints can cause surrounding muscle, ligaments and tendons to tear or rip away from bones, requiring surgery to reattach or repair them
EXERCISE
Moving arthritic joints might hurt, but if you don't exercise them regularly they can permanently freeze up
1. Water workouts
The buoyancy of water can help you move stiff joints without gravity's weight-bearing pressure
2. Recumbent bicycle
The reclining position takes the burden off such susceptible joints as the knees and hips
3. Walking
If it doesn't hurt too much, walking is one of the best ways to keep joints from the ankles to the shoulders from seizing up
4. Low impact aerobics
Any exercise that doesn't put pounding pressure on the joints can help build up muscle and keep ligaments and tendons flexible enough to give the joints the support they need
ALTERNATIVE THERAPIES
If taking standard pain-relief medications makes you uncomfortable, you may want to consider some of these alternative remedies
1. Acupucture
The Chinese traditionally believed it relieves pain by realigning of (life energy). Western doctors think the judicious placement of needles might actually work by stimulating the release of endorphins, the body's own painkillers
2. Glucosamines
Preliminary evidence suggests that these supplements, derived from lobster and crab shells, might help relieve arthritic pain possibly by encouraging cartilage growth
3. Chondroitin sulfates
Chondroitin is believed to help keep cartilage from breaking down; many arthritis sufferers take it with glucosamines
PREVENTION
While there is no guarantee that anything you do will prevent osteoarthritis, here are some steps you can take to keep your cartilage as healthy as possible
1. Keep Moving
Flexing joints lubricates and protects them, so exercise regularly. But avoid high-stress activities that pound on knees or hips
2. Stay Slim
Carrying too much weight puts extraordinary stress onto the knees, hips and ankles. Shed excess pounds to take a load off the joints
3. Build Muscle
Joints need a strong support system; maintaining muscle tone will help stabilize knees, hips and shoulders
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