Knee replacements on the rise in the U.S NEW YORK (Reuters Health) - More seniors are getting their knees replaced with artificial joints, according to a new study of Medicare data. Researchers found that over the last two decades, the number of first-time knee replacements and re-do procedures more than doubled in the U.S. By 2010, 62 out of every 10,000 older adults were getting primary knee replacement surgery every year, they reported today in the Journal of the American Medical Association. The procedure is typically considered for people with very bad knee pain, often accompanied by advanced arthritis, who haven't gotten relief from anti-inflammatory drugs or physical therapy. "As people are aging healthier than they used to, they want to maintain their activity throughout their lives," said lead author of the new study Dr. Peter Cram, from the University of Iowa Carver College of Medicine in Iowa City. "They want to play with their grandkids, they want to ski, they want to hike the Appalachian Trail - and knee replacement allows them to do that," he told Reuters Health. But, he said, "At $15,000 a pop, this adds up to real dollars." Cram and his colleagues found that between 1991 and 2010, the number of people seeking original or so-called revision knee replacements grew much faster than the number of elderly patients covered under Medicare: the rate of primary surgeries doubled and the rate of re-dos increased by almost 60 percent. At the same time, the proportion of knee replacement patients with underlying health problems such as diabetes and obesity also doubled. The researchers found that the average time spent in the hospital after a knee replacement dropped from almost eight days to 3.5 days. But the need for re-admission to the hospital increased slightly, and there was no change in the rate of serious complications such as infection or heart problems linked to a first-time procedure. Over the entire study period, one out of 200 patients or fewer died within a month of surgery. During a knee replacement, doctors remove damaged cartilage and bone from around the joint and replace them with an artificial joint made out of metal or plastic. Months of extensive rehab are required after the procedure - with full recovery typically taking six months to a year, according to orthopedic surgeon Dr. James Slover of the New York University Langone Medical Center, who co-wrote a commentary on the new study. He said after recovery, people who've had a knee replaced typically become healthier because they're able to move around better. Thus they may require less health care in the future, cutting down on related costs. "We don't really know what the exact per capita usage should be, and it's even possible that despite this data, (knee replacement) is underutilized in some populations," Slover told Reuters Health. Cram said although there's no doubt the procedures benefit patients' quality of life, the idea that they will create a net cost savings is "creative accounting and wishful thinking." "It's hard to envision how it actually saves money," he said. Knee replacements are covered by Medicare, the government-run health insurance program for the elderly, and typically by private insurance as well, according to Cram. An insured patient may have to pay $1,000 or $2,000 out of pocket. Both he and Slover said the number of knee replacements done in the U.S. is likely to continue growing as baby boomers age and people who've already had the surgery need it re-done. "What we're seeing now may be the tip of the iceberg for what we're seeing in 20 or 30 years," Slover said. SOURCE: bit.ly/JjFzqx Journal of the American Medical Association, online September 25, 2012.