There have been numerous research studies over the years related to knee pain due to arthritis. Today, arthroscopic surgery for mild arthritis and meniscus tears is common. A recent study published in the journal of the Canadian Medical Association looked at data from numerous studies related to this procedure. In that study it was found that the evidence pointed to "no benefit" from this type of arthroscopic surgery. Here is the original study for those who would like to see it. Perhaps we will start coming to an end to this very expensive, painful, and potentially useless surgery.
Not surprising, less invasive therapies such as acupuncture actually perform well for knee pain. Also, when compared to other therapies, acupuncture is one of the most effective for pain due to arthritis of the knee.