Undergoing arthroscopic knee surgery for mild age-related tears of the meniscus — the cartilage that helps stabilize the knees — offers no greater benefits than nonsurgical treatments or even placebo (sham) surgery, according to a new meta-analysis published Monday in the Canadian Medical Association Journal (CMAJ).
The findings strike yet another blow against the procedure. This study, which was conducted by researchers at McMaster University in Ontario, Canada, found that arthroscopic surgery tends not to help middle-aged and older people whose meniscus has deteriorated due to age and wear. Two previous large and well-designed randomized controlled clinical trials (published in 2002 and 2008) reported that arthroscopic knee surgery is also ineffective for severe knee arthritis.
Yet the procedure — also called arthroscopic meniscal debridement — is one of the most commonly performed orthopedic surgeries in the world. Each year, more than 700,000 people undergo the operation in the United States, and more than 4 million do so globally, according to background information in the curent study.
Seven studies, six countries
As people age, the meniscus thins and becomes more susceptible to tears. Arthroscopic surgery uses tiny (keyhole-like) incisions to remove torn pieces of cartilage from the knee and to smooth out rough areas of the remaining cartilage. The purpose of the surgery is to reduce pain and improve mobility.
The procedure is minimally invasive, but it does carry some risks for the patient, including blood clots and infection. For that reason, write the authors of the new study, it’s important to evaluate just how effective the procedure is for reducing both short-term and long-term knee pain.
For their meta-analysis, the researchers analyzed the findings from seven randomized trials — the gold standard of medical research. The studies, which were conducted in six different countries and published during the last seven years, involved 805 patients (average age: 56) with age-related meniscal tears and mild or no osteoarthritis. Some of the patients underwent the surgery, some underwent sham surgery and others had no surgery.
The analysis found no significant difference in relief from pain or in improved functioning (ability to walk, climb stairs and do other daily physical activities) at either six months or two years between the patients who had the surgery and those who didn’t.
(FYI: These findings apply only to people with age-related meniscal tears, not those who experience a sudden tear — say, from a sports injury.)
Physical therapy first
Like all studies, this one has its limitations. For example, some of the patients changed treatments while in their studies, which may have muddied the results.
Still, the findings support growing evidence that arthroscopic knee surgery is ineffective for many, if not most, of the people who are undergoing it annually. The authors of the meta-analysis urge physicians to do a better job of selecting patients for the procedure and to suggest conservative treatment — physical therapy and anti-inflammatory medications — first.
You can read the study in full on the CMAJ website.