By Amy Norton
TUESDAY, March 24, 2015 (HealthDay News) -- More and more middle-aged Americans are replacing their hips damaged by severe arthritis -- a surgery that used to be largely reserved for elderly people, a new study reports.
Researchers found that between 2002 and 2011, the rate of hip-replacement surgery nearly doubled among Americans ages 45 to 64. By 2011, those middle-aged patients accounted for over 42 percent of all hip replacements nationally -- up from 34 percent in 2002.
It's a striking change in a fairly short amount of time, according to lead researcher Dr. Alexander McLawhorn, an orthopedic surgeon at the Hospital for Special Surgery in New York City.
"I think we were a bit surprised by the magnitude of the increase," said McLawhorn.
However, he noted, the findings are consistent with government figures released just last month. That study found that the number of hip replacements nationwide soared between 2000 and 2010 -- particularly among people ages 45 to 54, whose rate rose by over 200 percent.
McLawhorn is scheduled to present the findings on Thursday at the annual meeting of the American Academy of Orthopedic Surgeons, being held in Las Vegas. Findings presented at meetings are generally considered preliminary until they've been published in a peer-reviewed journal.
McLawhorn's team suspects one key factor that may be driving this new trend: growth in the number of middle-aged Americans.
"But I definitely think there are other factors driving the trend, too," McLawhorn said.
Improvements in the artificial joints' durability, and surgeons' growing willingness to place them in younger, more active people might also be factors behind the increase, he said.
Plus, he said, patients with severe arthritis are increasingly open to the option. "I think there's been a shift in the public perception of what your function will be like after a total hip replacement," McLawhorn said.
The hip is a ball-and-socket joint, with the head of the thighbone fitting into a cup in the pelvis. During total hip replacement, those portions of bone are replaced with artificial components, usually made from metal and plastic. Most often, people end up needing the surgery due to severe osteoarthritis -- where the cartilage cushioning the hip bones breaks down, causing pain and stiffness.
And that helps explain why more middle-aged Americans are having their hips replaced, according to Dr. Claudette Lajam, an orthopedic surgeon at NYU Langone Medical Center in New York City.
"With the aging baby boomers, you have an entire generation who started playing sports and exercising when they were little kids," said Lajam, who was not involved in the study. "Their parents didn't do that. They walked for exercise, but most of them weren't playing sports or going to the gym."
"So now you have this large population with a lot of wear-and-tear in their hips," Lajam said.
For the study, McLawhorn's team used a government database on U.S. hospital admissions. Between 2002 and 2011, they found, the annual number of total hip replacements among 45- to 64-year-olds rose from about 68,000 to 128,000 -- an 89 percent increase.
The rate among older Americans also rose, but by 37 percent.
According to Lajam, the million-dollar question is, how long will a hip replacement done today ultimately last?
McLawhorn agreed. It always varies from one person to another, depending on factors such as body weight and activity levels, he pointed out. But with more Americans having the procedure in their 40s and 50s, the need for "revision" surgery will undoubtedly grow, both he and Lajam said.
And the procedure can cause complications. Another study to be presented at the meeting highlights some of the uncommon yet serious risks: blood clots and heart attack within a few months of the surgery, and infections and revision surgery within a couple years.
Few patients in the study suffered those complications -- less than 1 percent had a heart attack, for example. Men were slightly more likely to have these serious complications than women, but the risk was still low. However, people should be aware the surgery comes with potential risks, according to Lajam.
"Let's be clear," she said. "This is for people with severe arthritis that does not get better with other therapies."
It's also important, Lajam said, to have realistic expectations of what your life will be like after a hip replacement. "This is not a fountain of youth," she said. "It's more like a fountain of middle-age. It will help you get back to the function you had when you were 40."