Young Knee Ails Can Triple Arthritis
Sep. 11, 2000
WASHINGTON (AP) _ You may think you rebounded fine from that knee injury playing hoops or soccer at age 16, but it could haunt you by your 40s or 50s.
Scientists are proving what some sufferers have long suspected: A single knee injury as a teen-ager or young adult can triple the risk of arthritis in that knee by middle age.
Now researchers are seeking ways to prevent injured knees from deteriorating, and joint specialists say doctors must start telling young patients, especially athletes, how to protect their knees.
Nobody's advising giving up sports _ most Americans don't exercise enough _ but some simple precautions may make a big difference.
``I can't tell you how many people I've seen who say, 'I played college basketball and injured my knee but I still play on weekends, I just run through the pain,''' well-known arthritis expert Dr. Roland Moskowitz said with a sigh.
``Pain is nature's way of telling you there's something wrong here,'' said Moskowitz of Cleveland's Case Western Reserve University.
Nearly 21 million Americans suffer osteoarthritis, the form of the joint disease typically caused by the wear-and-tear of aging. The smooth, slippery cartilage that cushions joints over time becomes rough and cracked, causing pain and stiffness that can become severe as the cartilage continues to disintegrate.
It can hit any joint, but knees are particularly vulnerable. Some studies have found knee injuries in middle to old age, when joints are deteriorating, accelerate arthritis. So Johns Hopkins University rheumatologist Dr. Allan Gelber wondered if earlier injuries, when your body still heals easily, played a role.
Gelber used a study of 1,337 Hopkins medical school graduates who underwent rigorous health exams before graduating some 40 years ago and then were monitored each year since.
People who injured a knee before age 22 had a threefold increased risk of getting arthritis in that knee, and it typically struck by the mid-50s, he found. The cumulative risk rose to fivefold when Gelber also counted injuries suffered later in life.
Injuries included ligament or cartilage tears and bone fractures. Football, basketball and skiing were common causes, but car accidents and falls were culprits, too.
If the injury heals, why would it matter? Because even mild damage throws off a joint's biomechanics, Moskowitz explained. ``You may not see change day to day, but year to year you'll see the change.''
Consequently, said Gelber, ``We must find ways ... to prevent knee injuries.'' Athletes could be given easy-to-use knee guards to prevent injuries, and they could play on better terrain, avoiding artificial turf that is much harder on knees than grass is, he said.
Researchers are hunting for protective treatments for injured joints. For example, preliminary studies suggest tissue engineering _ using patients' own cells to grow new cartilage in a laboratory and then transplanting that tissue into their knees _ works better on a new, small injury than it does once arthritis strikes, Moskowitz and Gelber say. But it's a cumbersome, expensive treatment, so scientists are trying to create a single-injection method.
Other researchers are questioning if the arthritis treatment hyaluronate also might help stave off the disease, and drug companies are developing chemicals that might one day block cartilage-destroying enzymes.
Until such research is reality, specialists advise some commonsense precautions for battered knees:
_See a doctor right away if a knee injury causes severe pain or if swelling lasts more than 24 hours, says Dr. John Klippel of the Arthritis Foundation. Also seek help if pain lasts more than a few days. You may need a brace, restricted activity or surgery _ although Gelber cautions that some cartilage operations themselves have been linked to arthritis, so ask about options.
_Lose weight. Being overweight is an arthritis risk, so adding pounds adds trouble to an injured knee.
_Try joint-friendly exercise, like swimming. A fast walk on a treadmill is easier on knees than jogging. Whatever the exercise, do stretches first to limber joint-supportive muscles. Proper strength-training is important _ people with stronger quadriceps muscles are less likely to get arthritis, Moskowitz says.
_If giving up a favorite sport isn't an option, wear a supportive brace even after the knee heals _ and don't play in pain.
_For a mild injury, a shoe lift helps stabilize the knee, Moskowitz says; a rheumatologist or orthopedist can fit them.
EDITOR'S NOTE _ Lauran Neergaard covers health and medical issues for The Associated Press in Washington.
On the Net: Arthritis Foundation, http://www.arthritis.org