According to the American Orthopedic Society Sports Medicine, worldwide, more than 4 million people get arthroscopic knee surgery each year.

During the operation, a surgeon makes a small incision in the knee and inserts a tiny camera called an arthroscope to view the inside of the joint, locate and diagnose the problem, and guide repairs. Sometimes surgeons remove all of the meniscus, the cartilage that works as a cushion between the shin and thigh bones, and other times they only remove part of it.

While this is minimally invasive, it’s not risk-free. Patients receive anesthesia, which in any surgery may lead to complications such as allergic reactions or breathing difficulties. In addition, this specific procedure might potentially damage the knee or trigger blood clots in the leg.

A review of past studies published in the British Journal of Sport Medicine by researchers, and reviewed by Reuters Health, suggests that many middle-aged and older adults with torn cartilage and pain in their knee are not likely to benefit from arthroscopic surgery.  

Researchers analyzed 10 previous clinical trials that randomly offered some patients knee surgery and others nonsurgical options including exercise or medication. Overall, knee surgery was no better than these alternatives for improving physical function, and resulted in only a small reduction in pain.

In the current analysis, all of the trial participants who got knee operations had a partial meniscectomy, removing only some of this cartilage.

For all types of patients – including people with and without arthritis pain – surgery was slightly better than physical therapy at reducing pain after 6 to 12 months, an analysis of five trials with a total of 943 patients found.

However, when researchers looked just at a subset of patients without knee pain from arthritis in their knee, surgery did appear moderately better than physical therapy for reducing pain from the tear.

In three trials of 402 patients without arthritis pain, surgery had a small to moderate advantage in knee pain improvement after 6 to 12 months over physical therapy.

Two trials with 244 patients without arthritis pain also found surgery associated with a moderate to much larger improvement in quality of life than nonsurgical treatment.

“Surgery does not work for everyone but in selected cases we show that surgery should be available to patients,” said lead study author Simon Abram of the University of Oxford in the UK.

“In most circumstances, patients should try physiotherapy first,” Abram said by email. “If this does not improve symptoms, knee surgery may be beneficial, especially in patients without osteoarthritis and with specific symptoms.”