Times have changed. In 2010, 39% of the 453,663 patients who received hip replacements were under age 65, according to the Agency for Healthcare Research and Quality. And 42% of that year’s 721,443 knee replacements were performed on patients ages 45 to 64. What’s more, the number of joint-replacement recipients in that age group is expected to increase sixfold by 2030. MORE: How to Prevent Osteoporosis Why are so many people too young for Social Security seeking new joints? One reason is that we play more sports and work out more than our parents did, and have refused to give up these activities as we’ve grown older. “Playing competitive sports well into your 50s or later may lead to more wear and tear on joints at younger ages,” says Rocco Monto, MD, a spokesman for the American Academy of Orthopaedic Surgeons. Surprisingly, even golf, a seemingly joint-friendly sport, can place significant stress on your knees because of all the twisting involved. (Bicycling and swimming, however, are genuinely much easier on the joints.) Some joint injuries, even if they heal, may set off a gradual decline in the joint’s cushioning that leads to greater damage and even arthritis. MORE: Are Your Hips Behind Your Knee Pain? Then there’s the opposite problem that’s fueling the trend: being overweight and out of shape. Because of the physics of body structure, for each pound of weight gained, pressure on the hips and knees increases by 3 pounds. That means the joints feel 15 pounds of extra body weight as 45 pounds, which is likely why the obese, who are one-third of the population, account for more than 50% of patients having joint surgery. The good news is that as the need for joint replacements has risen, the surgeries themselves have improved dramatically. Changes in surgical technique as well as improvements in pre-and postoperative protocols, pain management, and anesthetic administration have resulted in a less painful, quicker recovery. Healthy patients may spend only 1 night in the hospital, and most joint recipients can resume their normal activities in 6 weeks, says Craig Della Valle, MD, an orthopedic surgeon who specializes in joint replacement at Rush University Medical Center in Chicago. Better yet, patients may not need to get that second surgery as soon as they’d thought—if ever. “The vast majority of these joints—80 to 90%—are still performing well at 20 years after the surgery,” Dr. Della Valle says. “Try to think of something you bought that was still working 20 years later.” The longer life of artificial joints is primarily due to the availability of better materials, including wear-resistant weight-bearing plastic. Finally, there’s the snowball effect. As the surgery becomes simpler and less traumatic, more people are willing to try it and to share their success stories with friends, Dr. Monto says. “There’s a more general acceptance. People used to see the need to have a joint replacement as a sign that they were growing old,” he says. “Now it’s considered a way to restore their vitality.” Here’s what you need to know if you’re considering joint replacement:  No procedure is risk free. The top dangers in joint-replacement surgery are infection, blood vessel or nerve damage, blood clots, and fracturing of bone around the implant. Certain factors increase your surgical risks. These include smoking, having diabetes, being overweight, and being out of shape, all of which contribute to cardiovascular problems. Control these conditions and you lower your risks. Your choice of surgeon matters. How well the surgery is performed makes a difference in the risk of early complications and the durability of the replacement. Select a surgeon with a great deal of experience, preferably one who specializes in joint-replacement surgery. You’ll need to take time off from work. Healthy patients usually leave the hospital after one night. But it can still take 3 to 4 weeks before you’re mobile enough to drive or resume a desk job. Rehabilitation takes time. After joint-replacement patients leave the hospital, physical therapy—at home and then as an outpatient—can last up to 3 months, though some people may reach their goals faster. (See why tennis pro Billie Jean King says rehab is vital post-knee replacement surgery.) [header = Exercises That Save Your Knees] The top knee-saving exercises If you have knee problems, you probably already know that low-impact workouts, weight control, and proper footwear are key to protecting your joints while you stay active. But there’s one more important step you should take: Build your leg muscles. “When the surrounding muscles are strong, they take pressure off the joints, which allows for greater activity with fewer aches and pains,” says Jordan D. Metzl, MD, sports medicine physician at the Hospital for Special Surgery in New York City. Exercises that strengthen the quads, hips, and glutes (think squats and lunges) are musts. Aim to do 2 or 3 sets of 10 reps of each 3 times weekly. (And check out these 3 at-home routines for strengthening and toning legs.) Can a supplement save your joints? There’s no substitute for proper exercise and weight control, but judicious use of the right supplements can enhance their effectiveness. Below, what the research has to say about the most popular options.

Proven effective: SAMe (S-adenosylmethionine) This naturally occurring compound plays an important role in maintaining cell membranes. Studies have shown the supplement to be as effective as nonsteroidal anti-inflammatory drugs in reducing morning stiffness, pain, and swelling while improving range of motion and walking pace, with fewer potential side effects. (For an additional health boost, take any—or all!—of these 8 best supplements for women.)Worth considering: Glucosamine and Chondroitin Usually taken together, these supplements are found naturally in joint cartilage and are thought by some to slow its natural breakdown. While patients and doctors report some success with these supplements, there’s only one large study so far that supports their use in treating moderate-to-severe cases.Wait for more evidence: Membrell JointHealth A relative newcomer, this supplement, which has Natural Eggshell Membrane (NEM), is believed to enhance joint flexibility and comfort. NEM is made of ingredients similar to those in human joints, including proteins that rebuild cartilage. While one small study suggests it has promise, the jury’s out until there’s more research.

Still on the fence? Here, two readers tell you what it’s really like to have joint replacement. Melody RoweAge: 62Hometown: South Jordan, UTJoints replaced: Right knee, 2006; left knee, 2009 Life before replacement: For 25 years, I had arthritis. I also tore the meniscus in my right knee. Surgery and recovery: My right knee was replaced when I was 56; my left, when I was 59. After each surgery I used a continuous passive motion machine day and night for several weeks to prevent inflammation. I got up every couple of hours to walk, using a walker, and then switched to a cane. At 3 weeks, I started going up and down stairs slowly. I took pain meds for about 4 weeks. Six weeks after each surgery, I started working back into my normal routine. Life today: I was just officially certified as a Zumba instructor. My knees are doing really well, and I feel fantastic! (Should YOU try Zumba? One Prevention editor thinks you should.) Mary Ellen SiebenAge: 54Hometown: Torrance, CAJoint replaced: Left knee, 2011 Life before replacement: I’ve been playing sports since I was 12. In my late 20s, I tore my ACL but didn’t get surgery and kept playing soccer until I was 40. Surgery and recovery: My left knee was replaced on Dec. 5, and that afternoon I was able to walk with a walker. I did physical therapy twice a day at the hospital and went home in 3 days on crutches. After 6 weeks, I started using an exercise bike without resistance and doing Pilates. I went back to work after 10 weeks—part-time for the first 2 weeks. Life today: I do Pilates and attend BFit BStrong fitness classes twice a week. Thanks to this regimen, my quads are much stronger, and I can do modified lunges and squats. I avoid running but could do it if I had to—if I were in danger, I’d be able to get out of the way fast! (Interested in Pilates? Here’s how to get started.) MORE: 3 Moves For Stronger Knees