October 2008

Arthroscopic knee surgeries generally useless, studies show

In the United States alone, close to a million arthroscopic knee surgeries are performed each year, generating some $70 billion for the medical industry -- despite the fact that a major study in 2002 concluded that, for people with arthritis, the operation was no better than sham surgery.

Two new studies, both published in a recent issue of the New England Journal of Medicine, have confirmed that earlier finding.

In one, researchers concluded that arthroscopic surgery for osteoarthritis of the knee provides no additional benefit to optimized physical and medical therapy. The other revealed that incidental meniscal findings on MRI of the knee are common in the general population and increase with increasing age. These commonplace tears in knee cartilage are often used as the excuse for arthroscopic knee surgery.

The first study, conducted in Canada at the University of Western Ontario, involved patients with moderate-to-severe osteoarthritis in the knee. Out of 172 patients, 86 received medication, a three-month term of weekly physical therapy and instruction on twice-daily exercises to do at home. The other 86 patients received the same treatments, plus underwent arthroscopic surgery. After two years, there was no significant difference in the pain levels, physical function and overall quality of life between the two groups.

In the second study, researchers reviewed MRI knee scans from 991 people. Subjects were between 50 and 90 years of age and ambulatory. Selection was not made on the basis of knee or other joint problems. Overall, about one-third of all subjects showed MRI evidence of meniscal tears in their knees. Most -- some 61% -- had exhibited no pain, aching, or stiffness during the previous month. There was no indication of the need for surgery in these patients.

In an accompanying editorial, Dr. Robert G. Marx of the orthopedic surgery department at the Hospital for Special Surgery (HSS) in New York attempted to justify the surgeries, saying that the study has some weaknesses and arguing strongly that arthroscopy is beneficial for some patients with osteoarthritis.

HSS performs more than 20,000 orthopedic surgical procedures per year, focusing mainly on the knee and hip.

SOURCES: "A Randomized Trial of Arthroscopic Surgery for Osteoarthritis of the Knee," and "Incidental Meniscal Findings on Knee MRI in Middle-Aged and Elderly Persons," New England Journal of Medicine, Sept. 11, 2008.