March 12, 2010 -- As they reach their 60s and beyond, baby boomers are increasingly opting for surgery to replace their worn-out knees.
More than half a million total knee replacement procedures are performed annually in the U.S., and this number is projected to climb to around 3 million per year over the next several decades.
Now, a timely study should reassure those considering going under the knife to escape knee pain.
One year after surgery, 95% of the more than 7,000 patients surveyed reported being happy with their new knees.
The study is the largest to examine satisfaction with total knee replacement surgery among patients treated over the last decade, orthopaedic surgeon and study researcher David Christopher Ayers, MD, of the University of Massachusetts Medical School tells WebMD.
Ayers presented the findings Thursday at the 2010 annual meeting of the American Academy of Orthopaedic Surgeons in New Orleans.
"Ninety-five percent is an astonishing number, and it points to how successful this operation is for relieving pain and restoring function to patients who can no longer control their pain with medication," Ayers says.
The study participants came from 32 states and were treated by 200 surgeons practicing at both academic and non-academic surgical centers.
Two-thirds of the patients were female and over the age of 65, and the vast majority (95%) had a diagnosis of osteoarthritis.
One Patient's Story
Public relations specialist Robin Mayhall of Baton Rouge, La., now 40, was just 27 when she had two operations to replace both knees.
"It was absolutely life changing," she tells WebMD. "There is no doubt about it. It is the best thing I ever did."
Mayhall was much younger than most knee replacement patients when she had her surgery. But her knees were so damaged from rheumatoid arthritis that the decision was a no-brainer.
"It had gotten to the point where I had to take [the painkiller] Vicodin every day to continue working," she says. "I would come home from work completely exhausted with no energy to run errands or do anything fun."
Twenty-four hours after having her first surgery, Mayhall was in less pain than she had been prior to her operation. Within three weeks she was working part time.
She recognizes her experience is not typical and says her young age and relatively good health probably played a role in her quick recovery.
Prolonged postsurgical pain and long recovery times continue to be a challenge with total knee replacement surgery, says Clifford Colwell, MD, who is medical director of the Shiley Center for Orthopaedic Research and Education in San Diego.
Younger patients and women were the most likely to express dissatisfaction with the surgery one year later in the new study.
Not surprisingly, dissatisfied patients reported more persistent knee pain than satisfied patients.
Colwell says he is not surprised that 95% of surveyed patients were happy with the results of their surgery one year later.
But he points out that when patients are surveyed three months and even six months after surgery, satisfaction rates tend to be much lower.
"The overall results from knee and hip replacement surgery are about equal, but knee replacement patients tend to have a tougher time and a longer recovery," he says.
While some patients feel fine in as little as three weeks, others take three to six months to recover.
"We are doing much better managing postoperative pain and reducing recovery times, but we still have a ways to go," he says.