With more people refusing to live in pain, knee replacement has become a common surgery. (ISTOCKPHOTO)

Americans are wearing out their joints. Knee replacement is now among the most common major surgeries, up 162 percent in the past two decades, according to an analysis of Medicare data published in September in the Journal of the American Medical Association.

The increase is partly due to the population growth of aging baby boomers. It also reflects rising rates of obesity and the fact that a more active group of people is unwilling to live with the pain and disability of osteoarthritis.

Surgery to replace joints is a good option if your condition has become disabling. But it’s possible to delay or prevent the need for surgery, even if you already have symptoms. Following is a roundup of evidence-based approaches that can help protect your joints and minimize the painful symptoms of arthritis.

Achieve a healthy weight. “Obesity is one of the most important modifiable factors contributing to the need for joint replacements,” says Joseph D. Zuckerman, chairman of the Department of Orthopaedic Surgery at the NYU Langone Medical Center in New York. Being overweight increases the stress on your joints and might even hasten the breakdown of cartilage. Fortunately, even modest weight loss — as little as 5 percent of your body weight — has been shown to reduce the risk of arthritis later.

Stay active. Because osteoarthritis can arise from the overuse of joints or from sports injuries, some people who have the condition worry that exercise will make it worse. In fact, the opposite may be true. Limited evidence suggests that routine physical activity is linked to healthier cartilage in the knees, according to a 2011 review of 28 studies. Along with regular aerobic exercise, aim for two to three sessions a week of strengthening activities using weights, resistance bands or your body weight (such as push-ups and squats).

Treat injuries promptly. Left untreated, injuries such as a small tear in the knee cartilage or a shoulder tendon can set in motion a wear-and-tear process that leads to joint deterioration. See a doctor for any injury that causes severe pain or swelling, or minor pain that doesn’t resolve after a week or so. Perhaps more important, take steps to minimize the risk of injury in the first place. For example, don’t wear running shoes, which are designed to keep your weight from shifting sideways, to play tennis.

Consider nondrug steps. Finding effective ways to alleviate pain, swelling and stiffness is critical to staying active. They include:

Acupuncture. Real acupuncture provided modest benefits over a sham procedure in relieving chronic pain, including pain due to osteoarthritis, according to a review of 29 clinical trials involving nearly 18,000 patients published in the Oct. 22, 2012, edition of Annals of Internal Medicine.

Heat and cold. Moist heating pads, a warm, damp towel, or a warm bath or shower can help relax and soothe stiff joints. Ice packs can help with acute pain and swelling.

Massage. Although there’s not a lot of scientific evidence on the effectiveness of massage in treating osteoarthritis, the deep-tissue variety got high marks in a 2010 survey of Consumer Reports online readers who had tried it.

Mechanical aids. A cane, crutch or walker can take a load off painful hips and knees.

●Simplify drug treatment. Newer, heavily advertised name-brand drugs such as duloxetine (Cymbalta) — which is approved for treating chronic musculoskeletal osteoarthritis pain in addition to its many other approved uses — may not work better than basic pain relievers, but they cost more and may carry a greater risk of side effects. Zuckerman advises patients to instead start with a tried-and-true pain reliever, such as over-the-counter acetaminophen (Tylenol and generics). For inflammation, try an over-the-counter nonsteroidal anti-inflammatory drug (NSAID), such as ibuprofen (Advil and generics) or naproxen (Aleve and generics). You can also talk with your doctor about the topical version of the NSAID diclofenac (Pennsaid and Voltaren Gel). Finally, shots of anti-inflammatory steroids can be an effective short-term remedy for moderate to severe pain and swelling in the knees and hips, especially during flare-ups.

●Use supplements wisely. Despite mixed evidence and a lack of support from major health groups about the role of the supplements glucosamine and chondroitin in treating osteoarthritis, some people think they help. It’s reasonable to try them if you want, Zuckerman says, but if you don’t experience relief within three months, there’s no point in continuing to take them.

Skip unproven treatments. In particular, the most recent data suggest that injections of hyaluronic acid directly into a joint, a treatment known as viscosupplementation, isn’t worth the risk. In a review last year of 89 clinical trials involving more than 12,000 patients, the authors concluded that viscosupplementation did little or nothing overall to relieve pain or increase function in people with knee osteoarthritis. But it did significantly increase the risk of side effects serious enough to result in hospitalization or disability.

Copyright 2012. Consumers Union of United States Inc.