NEW YORK (Reuters Health) – The results of a clinical trial suggest that arthroscopic surgery provides no advantages over rigorous physical therapy and drug treatment for treating age-related osteoarthritis of the knee.

“Although arthroscopic surgery has been widely used for osteoarthritis of the knee, scientific evidence to support its efficacy is lacking,” Dr. Robert B. Litchfield, from the University of Western Ontario in London, and colleagues note in The New England Journal of Medicine.

Arthroscopic surgery is done by making small incisions in the knee so an instrument called an arthroscope can be inserted. A small camera is attached to the tip of the pencil-size arthroscope to transmit images to a monitor to visualize the inside of the knee. The surgeon can then insert surgical instruments through the small incisions to repair or remove damaged tissue.

To assess the effectiveness of arthroscopy of the knee, the researchers evaluated arthritis symptoms and related outcomes in 178 patients who were randomly assigned to physical and medical therapy alone or in combination with arthroscopic surgery.

Arthroscopic treatment involved removal or repair of fragments or tissue that were considered to be responsible for the symptoms.

At 2-year follow-up, symptoms were similar in each group, as assessed using a number of standard scales. None of the tests showed any significant difference between the groups. The use of arthroscopic surgery also did not enhance physical function or quality of life, according to the report.

In patients with osteoarthritis of the knee with good alignment and no evidence of a large displacement or tear “arthroscopy is not effective,” Litchfield told Reuters Health. He recommends that all non-surgical methods of care first be exhausted, including analgesics, braces, injections, exercise and physical therapy, before surgery is considered.

In a related editorial, Dr. Robert G. Marx, from Weill Medical College of Cornell University in New York, points out that these findings support other evidence that osteoarthritis of the knee, in and of itself, is not an indication for arthroscopic surgery.

By the same token, however, arthroscopy for knee osteoarthritis can be useful under the right circumstances. If another pain-causing disease is also present, arthroscopic surgery may be an appropriate intervention, he adds.

SOURCE: The New England Journal of Medicine, September 11, 2008.