The most common knee surgery performed on people over 65 is repair of torn meniscus cartilage. The procedure is costly, at up to $10,000 a patient — and it's also usually a waste, if not outright harmful.
"It's known that this procedure is often done without strong evidence; I don't think it's well known that this is one of the most common surgeries in the U.S.," said Martin Makary, a professor of health policy at Johns Hopkins Medicine in Baltimore and author of a recent study in the Journal of the American Medical Association Surgery. "We not only described it, we looked at it in a population every American pays for (through Medicare). That's a price tag and a context I'm not sure people have really calculated."
That giant waste of money could be better spent on other treatments, from something as simple as Advil to more sophisticated courses of physical therapy that will give most patients better results, researchers at Johns Hopkins Medicine say.
The problem is that there are two kinds of meniscus tears, said David Altchek, an attending orthopedic surgeon at New York's Hospital for Special Surgery and the medical director for the New York Mets. Only one of the two tears, the much less common one, responds to surgery, Altchek said.
Arthroscopic procedures for acute injuries are fine and are often done in conjunction with physical therapy to rebuild strength in the joint. These are mostly done on younger patients, who get hurt doing everything from playing basketball to misstepping off a commuter train. The issue with seniors is that their meniscal injuries are more often the result of wear and tear, and they often or even usually coincide with osteoarthritis, Altchek said.
Indeed, the cartilage that wears out in seniors is a different kind of tissue than what is damaged in acute injuries — the cartilage that bothers older patients is usually articular cartilage, while younger patients injure meniscal cartilage.
Articular cartilage is usually found on the surface of bones in the knee joint, and when it wears out, it produces a duller ache. Meniscal cartilage is more like a pad between joints and can produce a sharper pain, especially when it's injured all at once rather than over time.
Arthroscopic meniscal surgery often can't repair degenerative damage to the meniscus cartilage effectively, and it doesn't treat the articular cartilage, which deteriorates due to arthritis in the knee.
It's not the age of the patient, but the presence of the arthritis that makes the surgery ineffective, Altchek said: "That is what reduces the quality of the outcome. It's usually the arthritis causing most of the symptoms."'
Hopkins researchers found that the common surgery, known as arthroscopic partial meniscectomy (APM), accounted for an estimated two-thirds of all orthopedic knee arthroscopy procedures in older patients in 2016. An estimated 750,000 such procedures are performed each year.
Of the 121,624 knee arthroscopies performed on Medicare recipients by 12,504 surgeons in 2016, APM-only procedures accounted for more than 81,000, or 66.7 percent, the Hopkins-led team reported.
Getting the usage of APM surgery right is part of a broader movement in health policy and academic medicine toward measuring the effectiveness of care, with an eye toward delivering treatments that work rather than responding to patient demand that's not based on hard data, Makary said.
"The goal shouldn't be to eliminate pain in everyone," Makary said. "It should be to supply medical [care] that the evidence shows will help.''
Main Street doctors say the academic data confirms what they see in their practices and is consistent with other studies showing that doctors too often prescribe arthroscopic procedures for older patients.
"The reasons for overprescribing this surgery are [many] but center on the fact that surgeons are treating patients that are in pain and are attempting to correct this," said Eric Grossman, director of hip and knee replacement surgery at CareMount Medical in Mount Kisco, New York. "Patients want options in treatment of their conditions, and fixes that might not always be realistic. ... The data is conclusive, and surgery in this population is a cautionary tale."
The better plan is to begin by increasing low-impact exercise, like swimming and biking, and slowing down on running and other exercise that puts more pounding on the knee joints, said Eric Mirsky, director of orthopedic surgery at Summit Medical Group in Berkeley Heights, New Jersey.
Practicing doctors are also pushing to squeeze out the unnecessary care because of the rising importance of value-based care reimbursement, which rewards doctors for delivering better results rather than performing more procedures, Mirsky said. "We want to know if we're giving the most bang for the buck," he said.
But doctors continue to push the limits of when the surgery is appropriate, sometimes in cases where knees locking, a symptom surgery can fix, coincides with more subtle signs of degeneration, Mirsky said.
So what should patients do?
First, ask themselves honestly whether their symptoms are coming more from their arthritis or their cartilage damage, Mirsky said. Physical therapy, cortisone injections and losing weight are all better, less-expensive strategies when most of the problem is arthritis.
"If the symptoms are atraumatic in origin and osteoarthritis is present, then surgery is unlikely to be effective and can actually worsen a patient's condition," CareMount's Grossman said. "I would encourage patients to ask what the actual success rates are of surgery vs. the alternatives and what option would they choose if they were the patient. And of course, if in doubt, always seek a second opinion."
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— By Tim Mullaney, special to CNBC.com